Question Bank on Agricultural Meteorology

Question Bank on Agricultural Meteorology

Mr. Sitanshu Sekhar Patra

Ph.D. Scholar and DST Inspire JRF

Department of Meteorology and Oceanography

Andhra University, Visakhapatnam, Andhra Pradesh

Pin-530003, India

Dr. Sandeep Rout

Assistant Professor (Forestry)

Faculty of Agriculture, Sri Sri University,

Cuttack, Pin -754006, Odisha, India

Dr. Sandeep V.M.

Research Associate

AICRPAM, ICAR- CRIDA,

Santosh Nagar, Saidabad PO

Hyderabad - 500059, India

Mrs. Kalyani Pradhan

Assistant Professor (Horticulture)

Faculty of Agriculture, Sri Sri University,

Cuttack, Pin -754006, Odisha, India

Mr. Gyanaranjan Sahoo

Scientist (Forestry)

Krishi Vigyan Kendra, OUAT, Angul, Pin-759132

Odisha, India

2020

Ideal International E – PublicationPvt. Ltd. www.isca.co.in

427, Palhar Nagar, RAPTC, VIP-Road, Indore-452005 (MP) INDIA

Phone: +91-731-2616100, Mobile: +91-80570-83382

E-mail: [email protected], Website:www.isca.co.in

Title: Question Bank on Agricultural Meteorology Author(s): Mr. Sitanshu Sekhar Patra, Dr. Sandeep Rout, Dr.

Sandeep V.M. , Mrs. Kalyani Pradhan, Mr. Gyanaranjan Sahoo

Edition: First Volume: I

© Copyright Reserved

2020

All rights reserved. No part of this publication may be reproduced, stored, in a

retrieval system or transmitted, in any form or by any means, electronic,

mechanical, photocopying, reordering or otherwise, without the prior permission

of the publisher.

ISBN: 978-93-89817-33-1

3

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CONTENT

Sl. No Chapter Pg No.

1. The Atmosphere 01

2. Radiation 02-07

3. Air Temperature 08-11

4. Soil Temperature 12-16

5. Air Pressure 17-25

6. Atmospheric Moisture 26-29

7. Clouds, Their Types & Classification 30-34

8. Rainfall 35-43

9. Soil Moisture 44-47

10. Weather in the Incidence of Pests Diseases 48-52

11. Drought 53-54

12. Weather Forecasting 55-56

13. Remote Sensing 57

14. Crop Modeling and Its Application 58

15. Key TakeDowns 59-75

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Chapter 1. THE ATMOSPHERE

1. Which chemical forms during lightning in the atmosphere?

Ans:-NH4

2. Nitrogen forms about……………% of the total volume of dry air.

Ans:-78.08

3. Oxygen forms about………% of the total volume of dry air.

Ans:-20.94

4. The top most layer of atmosphere is……………..

Ans:-Thermosphere

5. …………%of the total gaseous mass of atmosphere present in the troposphere.

Ans:-75%

6. Decrease in temperature with height in the troposphere is known as………..

Ans:-Lapse rate

7. The mean rate of decrease of temperature with height is…………..

Ans:-6.50C/km

8. Altitude of the troposphere above the equator is………km & over pole is………km.

Ans:-16,8

9. Higher temperature occurs in the stratosphere because of absorption of……by ozone.

Ans:-Ultraviolet radiations

10. Above stratopause average temperature decreases to minimum of about………0Caround

80km.

Ans:-90

11. Atmospheric densities are low in………..

Ans:-Thermosphere

12. Layer above 80km commonly known as…….

Ans:-Ionosphere

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Chapter 2. RADIATION

1. Radiation is a form of energy that is emitted by all objects having a temperature

above………

Ans:-Absolute Zero

2. Energy receipt & disposal form earth must be in the form of…………

Ans:-Radiation

3. X & γ rays having wavelength …..nm.

Ans:-0-300

4. UV rays having wavelength of……….nm.

Ans:-300-400

5. ………% of energy received by earth from PAR.

Ans:-39

6. The shortest distance between two consecutive points and the same phase on a wave

pattern is known as………..

Ans:-Wavelength

7. Number of vibrations per second is known as………..

Ans:-Frequency

8. The value of speed of light (c) is…………

Ans:-3x108 m/s

9. The ratio of speed light (c) to frequency (ν) is known as………

Ans:-Wavelength(λ)

10. The time period of one vibration is equal to……….

Ans:-1/Frequency

11. The wave number is equal to……….

Ans:- 1/λ (λ=Wavelength)

12. The energy received on a unit surface in a unit time is known as………….

Ans:-Radiant flux density

13. The SI unit of radiant flux density is……….

Ans:-W/m2 or J/m

2/s

14. The CGS unit of radiant flux density is…………

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Ans:-Cal/cm2/min

15. 1 cal /cm2/min =………W/m

2.

Ans:-697.93

16. ……….. is a physical ideal, perfect radiator and perfect absorber.

Ans:-Blackbody

17. The ratio of emittance of a given surface at a specified wavelength & temperature to the

emittance of an ideal blackbody at the same wavelength & temperature is known

as………….

Ans:-Emissivity (ε)

18. The emissivity of a blackbody is……………

Ans:-Unity or 1

19. The ratio of the amount of radiant energy absorbed to the total energy incident on it is

known as……….

Ans:-Absorptivity (α)

20. Absorptivity of a blackbody is………….

Ans:-Unity or1

21. Earth behaves in total as a ……….. body.

Ans:- Grey

22. The ratio of the radiant energy reflected from the surface to the total radiation incident

upon the surface is known as …………..

Ans:-Reflectivity(r)

23. The ratio of transmitted radiation to the total radiation incident upon the surface is known

as……………

Ans:-Transmissivity (t)

24. The sum of absorptivity, reflectivity and transmissivity of a surface at a specific

wavelength is equal to or less than………………

Ans:-Unity or 1

25. Which law states that a good absorber of radiation is also a good emitter under similar

conditions?

Ans:-Kirchhoff’s law

26. Value of Planck's constant is……………

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Ans:-6.626 x10-34

Js

27. The………………. the frequency the greater is the energy content of the quantum.

Ans:-Greater

28. The greater the frequency then …………the wave length.

Ans :-Shorter

29. Stefan-Boltzman constant is equal to……………….

Ans:-5.67 x 10-8

J/m2/s/

0k

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30. The value of Wein’s constant has value of ………….. µm0k.

Ans:-2897

31. By Wien’s law tmax of the sun is………….

Ans:-0.483µm

32. The solar radiations are known as……………

Ans:-Short wave radiations

33. The range of shortwave radiations (solar radiations) is………to…….µ.

Ans:-0.15 to 4.0

34. The peak of solar radiation is at………….

Ans:-0.483µ

35. The flux density C or intensity of the solar beam at the top of the atmosphere and at the

earth’s mean distance from the sun is known as……………

Ans:-Solar Constant

36. The value of solar constant estimates approximately as……………

Ans:-1.94 cal/cm2/min

37. Incoming solar radiation is known as……………

Ans:-Insolation

38. Direct radiations are those, which cast…………

Ans:-Shadow

39. Solar radiation directly received on a unit horizontal surface is called as……………

Ans:-Direct radiation

40. Before sunrise and after sunset all radiations received on a horizontal surface

are………radiation.

Ans:-Diffuse or sky

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41. The peak of earth radiation or long wave radiation is at…………µ.

Ans:-9.66

42. The long wave radiation radiated both from earth surface & atmosphere is also known

as………..radiation.

Ans: Terrestrial

43. The ozone and………of the atmosphere absorb most of U.V radiation.

Ans:-Oxygen

44. Ozone is a perfect absorber of U.V radiation up to……….µm.

Ans:-0.3

45. The ratio of reflected shortwave radiation to the incident shortwave radiation on a surface

is known as………….

Ans:-Albedo

46. Albedo of crop surface is ranging between…………

Ans:-23-30%

47. The total of all incoming and outgoing radiation over earth's surface is………….

Ans:-Zero

48. …………% of radiation is absorbed directly by ozone & water vapors.

Ans:-18

49. …………. % of radiation are absorbed by clouds.

Ans:-3

50. …………. % of radiation is absorbed by earth’s surface.

Ans:-48

51. About………% of energy is reflected back by the cloud.

Ans:-21

52. About……% of energy is reflected back by air, dust & water vapor.

Ans:-6

53. About ……% of energy is reflected back by earth’s surface.

Ans:-4

54. A maximum of infrared (long wave) radiation is emitted by the heated ground surface

at………time.

Ans:-12:00h (Mid-day)

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55. The flux/flow of heat into or out of the soil through a process of conduction is known

as…………

Ans:-Soil heat flux (S)

56. Soil acts as a…………for energy during the day and as……….at night.

Ans:-Sink, Source

57. The flux of the sensible heat between the surface and air near the surface is known

as……………

Ans:-Sensible heat flux(H)

58. During sensible heat flux the flow of heat is done through the process of…………

Ans:-Convection

59. Sensible heat flux is………during day time.

Ans:-Positive

60. Sensible heat flux is……………when heat is released.

Ans:-Positive

61. Sensible heat flux determines the…………

Ans:-Air temperature

62. The amount of heat required in the process of evaporation and the amount of heat

released in the process of condensation is nothing but……….

Ans:-Latent heat

63. The latent heat flux over wheat crop, at the flowering stage at midday is……%.

Ans:-101

64. The energy over 100% is due to……………

Ans:-Heat advection

65. Direct components of solar radiation at normal incidence are measured by……….

Ans:-Pyrheliometer

66. …………..measures the global solar radiation reaching the earth’s surface (W/m2).

Ans:-Pyranometer

67. The diffuse radiation (W/m2) is measured by………….

Ans:- Shading ring pyranometer

68. ………. measures the long wave radiation either is upward or downward direction

(W/m2).

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Ans:-Pyradiometer

69. The balance between upward and downward total radiant energy (W/m2) is measured

by……………

Ans:-Net radiometer

70. Sunshine recorder measures…………and……………

Ans:-Bright sunshine hour, cloudiness

71. Albedometer measures…………

Ans:-Total albedo

72. Number of photons received on a unit area per second (E/m2/s) is recorded by……….

Ans:-Quantum sensor

73. Illuminance (brightness) of light is measured with………or……………

Ans:-Lux Meter or Photometric sensors

74. The unit of Lux Meter is…………or…………..

Ans:-Foot candle(fc) or Lux(l)

75. 1K Lux=………fc.

Ans:-92.9

76. 92.9fc=……W/m2.

Ans:-4.0

77. Sensors used in quantum sensors and photometric sensors are made of………

Ans:-Photodiode

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Chapter 3. AIR TEMPERATURE

1. Temperature is a measurement of ………… of the molecules in the body.

Ans:-Speed (Kinetic energy)

2. The difference ………….. of two bodies indicated the direction of flow heat energy.

Ans:-Temperature

3. …………… is a measure of degree of hotness of a body whether solid, liquid or gas.

Ans:-Temperature

4. S.I Unit of temperature is…………

Ans:-0C

5. Thermodynamic scale uses…….as the unit.

Ans:-0K

6. 00C=…………

0K.

Ans:-273

7. K=C+………

Ans:-273

8. (F-32)/180=C/…..

Ans:-100

9. Taverage=……………

Ans-(Tmax+Tmin)/2

10. Preferably over…………or more years records are used to establish monthly and annual

temperature normal.

Ans:-30

11. The temperature decreases with the ………of latitudes.

Ans:-Increase

12. Water bodies are greater moderators of temperature because of high……of water.

Ans:-Specific heat

13. The maximum temperature recorded at………pm in a day.

Ans:-2-3

14. The half of the difference between the maximum and minimum temperature is called the

……….of air temperature.

Ans:-Amplitude of daily oscillations

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15. The difference between the maximum and minimum temperature is referred to as……….

Ans:-Daily range

16. The change of temperature with distance is known as …………

Ans:-Temperature gradient

17. The average global surface temperature is about………0C.

Ans:-13

18. …………exhibits the horizontal distribution of temperature across the latitude.

Ans:-Isotherms

19. The line on the map that joins the places of equal temperature is known as…………

Ans:-Isotherms

20. When the isotherms are far apart, the temperature gradient is…….. and vice versa.

Ans:-Weak

21. The change of temperature over a unit distance along the vertical is known as……or……….

Ans:- Vertical temperature gradient or lapse rate

22. A positive lapse rate means a……..of temperature with height.

Ans:-Decrease

23. Negative lapse rate is called as………….

Ans:-Inversion

24. The temperature lapse is irregular being the strongest in the ……….km layer.

Ans:-5-9

25. Lapse rate is measured in……………

Ans:-0C/km

26. The average lapse rate up to tropopause is……….

Ans:-6.50C/km

27. As the air ascends upward it encounters………….and get expanded due to which cooling is

produced.

Ans:-Low pressure

28. Any change in volume, pressure and temperature of air when it moves upward or downward

which takes place without any addition or removal of heat from the system is known

as………….

Ans:-Adiabatic change

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29. The air in stable equilibrium tends to resist………. movements.

Ans:-Vertical

30. If the vertical temperature gradient is less than…………. degree per 100m then the

atmosphere is in stable equilibrium.

Ans:-1

31. Radiation fogs, dew and frost usually occurs in…………condition.

Ans:-Stable

32. ………..is that state of air when air can be pushed up easily.

Ans: Instability

33. If the vertical temperature gradient is greater than…………. degree per 100m then the

atmosphere is in unstable equilibrium.

Ans:-1

34. Violent weather conditions usually occur during…………. condition.

Ans:-Unstable

35. Stevenson’s screen is always installed facing…………. direction.

Ans-North

36. The shelter of Stevenson’s screen is located at a height of………m from ground.

Ans:-1.2

37. The shelter of Stevenson’s screen is always painted ………..

Ans:-White

38. Dry bulb and wet bulb thermometers are…………thermometers.

Ans:-Mercury

39. Minimum thermometer is an ……………thermometer.

Ans:-Alcohol

40. Assmann psychrometer is also known as……………

Ans:-Aspiration thermometer

41. Assmann psychrometer was devised by Assmann in the year ……..

Ans:- 1887

42. ……………. keeps the wet bulb thermometer wet.

Ans:-Muslin cloth

43. Assmann psychrometer is used for the measurement of………… and ……………...

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Ans:-Vertical profile of temperature, humidity of the atmosphere

44. …………used for making a continuous record of the temperature changes in the

atmosphere.

Ans:-Thermograph

45. Thermograph consists of a …………to record the temperature changes in the atmosphere.

Ans:-Bimetallic strip

46. The bimetallic strip is generally……………in shape.

Ans:-Helical

47. ……………..is used to measure minimum temperature at the height of vegetation.

Ans:-Grass minimum thermometer

48. The minimum thermometer placed horizontally at…………cm height from ground.

Ans:-5 to 6

49. The minimum air temperature occurs at about……………

Ans:-Sunrise

50. The fall in temperature for every 100m rise in the free atmosphere is nearly……… 0C.

Ans:-0.5 to 0.6

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Chapter 4. SOIL TEMPERATURE

1. Germination is a slow process in……….soil.

Ans:-Cold

2. The incoming short-wave radiation and outgoing long wave radiation are highest in the

…………latitudes.

Ans:-Lower

3. Albedo is lowest in the……………regions and highest in the……….latitudes.

Ans:-Tropical, Lower

4. The cultivated soil has…………temperature amplitude as compared with the

uncultivated soil.

Ans:-Greater

5. Sandy soil warms up rapidly than clay due to………….

Ans:-Lower heat capacity

6. …………..reduces the heat capacity and thermal conductivity of soil but increases the

water holding capacity.

Ans:-Organic matter

7. Albedo for fresh snow is…………%

Ans:-75-95

8. Albedo of water is………… %

Ans:-3-10

9. Albedo of sand is………. %

Ans:-35

10. Albedo of forest is………%

Ans:-5-20

11. Albedo of bare field is………%

Ans:-12-25

12. The amount of heat absorbed or released in raising or lowering the temperature of a unit

mass of the material by 10C is known as…………

Ans:-Specific heat(Cs)

13. The product of mass density (ρ) and specific heat (Cs) is called as…………….

Ans:-Heat Capacity(C)

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14. Through solid media and still fluids, heat is transferred primarily through……………

Ans:-Conduction

15. In soil, thermal conductivity (K) can vary considerably with…………and……….

Ans:-Moisture content, Soil type

16. The ratio of thermal conductivity to the thermal capacity is known as………….

Ans:-Thermal diffusivity (k)

17. The c.g.s unit of thermal diffusivity is ………………

Ans:- cm2/sec

18. The reciprocal of thermal diffusivity, 1/k (sec/cm2) will control the time necessary for

soil elements to …………….. by conduction.

Ans:-Heat up

19. The larger the value of 1/k the………it will take to heat up.

Ans:-Longer

20. The larger the value of thermal ………….. will lead to rapid change in temperature.

Ans:- diffusivity

21. Thermal conductivity of water is……….than air.

Ans:-More

22. In dry soil the value of thermal diffusivity is …………….. cm2/sec.

Ans:- 5×10-3

23. Thermal conductivity of water is…………..

Ans:-1.4 × 10-3

cal/cm/sec/0C

24. Thermal conductivity of air is……………..

Ans:-0.062 × 10-3

cal/cm/sec/0C

25. The replacement of air between soil particles by water increases the…………….of the

medium as a whole.

Ans:-Thermal Conductivity

26. ……….. is the quantity of heat flowing in a unit time through a 1 cm2 cross section of the

soil in response to a temperature gradient of 10C/cm of depth.

Ans:-Thermal conductivity

27. The thermal conductivity of soil is observed to………….. with reduction in particle size.

Ans:-Decrease

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28. The thermal conductivity of quartz is …………………

Ans:-20×10-3

cal/cm/sec/0C

29. The thermal conductivities of quartz, water and air are in the ratio of…………..

Ans:-333:23:1

30. A dry and loose soil will be a…………conductor of heat compared to when it is wet and

compact.

Ans:-Poor

31. There is a ………… in thermal conductivity with fineness of the texture of soil.

Ans:- decrease (sand>loam>clay>peat)

32. The change in 0C that occurs in one second when the temperature gradient changes

10C/cm is known as…………..

Ans:-Thermal diffusivity

33. Thermal conductivity of water is about …………. times that of air.

Ans:- 23

34. In dry soil the increase in thermal conductivity with compaction is associated with

decrease in ………..

Ans:- porosity

35. The ratio between thermal conductivity and heat capacity is known as ………..

Ans:- thermal diffusivity

36. Specific heat of air is……………..

Ans:- 0.24 cal/g/0C

37. Specific heat of water is…………….

Ans:-1 cal/g/0C

38. Tillage causes……………. distribution of energy at the soil surface.

Ans:-Unequal

39. Ridging decreases …………..

Ans:- Albedo

40. The black plastic mulches ……… the outgoing radiation, while paper and straw mulches

………it.

Ans:-Reduces, increases

41. Outgoing radiation ……….. sharply under highly reflective aluminium.

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Ans:- increases

42. In warm weather, where temperature is not limiting but water is limiting ……... the

surface may conserve water and enhance germination.

Ans:-Whitening

43. The surface soil temperature ranges under polythene from ……. to ……. 0C.

Ans:-1.5 to 430C (Optimum at 27.5

0C)

44. The surface soil temperature range under bare soil ranges from …… to …… 0C.

Ans:-13.7 to 350C (Optimum at 21.3

0C)

45. Soil temperature fluctuations are …………. under straw and ………..under clear

polythene.

Ans:-Minimum , maximum

46. ………………is often practiced either to reduce the intensity of the direct radiation or to

conserve the soil crop canopy heat in the case of crops like tomato, brinjal and some

ornamental plants.

Ans:-Artificial shading

47. Tillage …………the soil porosity and ……….the thermal conductivity and heat capacity.

Ans:-Increase, Decrease

48. ……….. irrigation reduces soil temperature in both bare and cropped fields.

Ans:- sprinkler

49. Soil compaction increases the heat capacity and thermal conductivity due to an increase

in………..

Ans:-Bulk density

50. …………reduces the damage effects of frost.

Ans:-Soil Compaction

51. The WMO recommends as standard depths for soil temperature measurements are …… ,

…… , ….. and …… cm.

Ans:-10,20,50,100

52. For micro climatological and physiological studies, the soil temperature is measured at a

depth of ……… cm.

Ans:-2.5

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53. The flux of heat into and out of soil can be measured directly by means of…………….

Ans:-Thermal flux plates

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Chapter 5. AIR PRESSURE

1. When air pressure …………, more molecules are present in a given volume.

Ans:-Increases

2. P(pressure) =…………….

Ans-Force per unit area

3. 1mb=…………part of 1 bar.

Ans:-1000th

4. The unit of force is…………… or………….. or…………

Ans:-dynes/cm2, millibars, hecto pascals

5. 1 Pa=…………N/m2.

Ans:-1

6. A change in pressure (dP) is given by the change in head of fluid, dh with density ρ

and acceleration due to gravity g, dP= …………

Ans:-ρgdh

7. 1 Pa= …… dynes/cm2.

Ans:-10

8. 1 mb = …… Pa.

Ans:-102

9. 1mb=…… hPa= ……… dynes/cm2= ……… mmHg.

Ans:-1, 103, 0.750

10. 1mm Hg= ……… Pa.

Ans:-133.3

11. 1 atm= …… hPa

Ans:-1013.25

12. 1013.25mb= ……… mmHg.

Ans:-760

13. The standard atmospheric pressure at mean sea level and latitude of 450, at a

temperature of 00C is ……… mmHg.

Ans:-760

14. With increase in height, the air density…………

Ans:-Decrease

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15. Along the equator lies a belt of low pressure known as the ……… or………

Ans:-Equatorial low, doldrum

16. 600

to 700 north and south latitude are the………belts.

Ans:-Sub polar low pressure

17. 250

to 350 north and south latitudes are the……………

Ans:-Subtropical highs

18. Atmosphere is a ………… medium.

Ans:-Dynamic

19. The peak pressure occurs at …… AM and ……… PM.

Ans:-10:00,10:00

20. The low pressure occurs at………AM & ……….PM.

Ans:-4:00, 4:00

21. This low and high pressure is caused by the………. tide.

Ans:-Solar or Thermal

22. The imaginary lines that connect places having the same atmospheric pressure is

known as…………

Ans:-Isobars

23. Equatorial low is also known as…………..

Ans:-ITCZ

24. ITCZ Stands for……………

Ans:-Inter Tropical Convergence Zone

25. Closely spaced isobars indicate a ………… change of pressure in the direction at the

right angle to the isobars.

Ans:-Rapid or steep

26. When isobars are widely spaced, a…….change in pressure or a ……..pressure

gradient is indicated.

Ans:-Slow, weak

27. ……… never crosses each other.

Ans:-Isobars

28. The winds are the result of ……… pressure gradients.

Ans:-Horizontal

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29. The science of pressure measurement is known as……….

Ans:-Barometry

30. ………… type barometer has a fixed cistern.

Ans:-Kew pattern

31. The pressure sensitive element in an aneroid barometer is a cylindrical vacuum

chamber made up of………..

Ans:-Beryllium-copper

32. For continuous record of atmospheric pressure ……… is used.

Ans:-Barograph

33. The pressure sensitive element in a barograph is a …………

Ans:-Syphon bellow

34. Air in horizontal motion is known as …………

Ans:-Wind

35. Vertically moving air columns are called as………

Ans:-Currents

36. Average horizontal wind speeds are much……….than average vertical movements.

Ans:-Greater

37. Wind is a ………….. quantity.

Ans:-Vector

38. The primary cause of air movement is the development of a horizontal pressure

gradient developed due to the…………

Ans:-Temperature gradient

39. For horizontal variations in pressure, a force is created acting from high to low

pressure is known as…………….

Ans:-Pressure gradient force(P)

40. Closer is the isobar spacing, the more intense are the……………..

Ans:-Pressure gradient

41. Intense pressure gradient is related to greater……………

Ans:-Wind speed

42. ………… causes a change in the direction of the flow.

Ans:-Rotation

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43. The force created by rotation of earth is known as………….

Ans:-Coriolis force

44. On a rotating planet, the speed of the wind is governed by …………… force.

Ans:- Pressure gradient

45. Coriolis force is also known as ………… force.

Ans:-Deflective

46. The effect of Coriolis force is maximum at………..

Ans:-Poles

47. Coriolis force becomes ………. at the equator.

Ans:- Zero

48. The Coriolis force always acts at right angles to the direction of the ……… to

the……..in the northern hemisphere.

Ans:-Air motion, right

49. When the pressure gradient force and Coriolis force acting in diametrically opposite

directions comes into equilibrium and there is a balanced flow with two equal forces

the wind in this idealized case is called as………….

Ans:-Geostrophic wind

50. Velocity is inversely proportional to………….

Ans:-Latitude

51. ……………force acts outwards from the center on any curved motion.

Ans:-Centrifugal

52. The wind that results from a balance of the three forces (Pressure gradient force,

Coriolis force, centrifugal force) is known as the …………… wind.

Ans:-Gradient

53. The direction of gradient wind is parallel to the …………

Ans:- Isobars

54. ………… force acts directly against the airflow, leading to a reduction in wind speed.

Ans:-Frictional

55. The decrease of frictional force with height also leads to clock wise change in wind

direction with height, which is sometimes called as……………..

Ans:-Ekman spiral

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56. Frictional force becomes insignificant at the area of ……………

Ans:- Geostrophic wind

57. The surface wind represents a balance between the pressure gradient force and

friction is ………. to the air motion.

Ans:-Parallel

58. The surface wind represents a balance between the pressure gradient force & the

Coriolis is …………… to the air motion.

Ans:-Perpendicular

59. …………..is associated with convergence and ascending air.

Ans:-Low pressure

60. ………..is associated with descend and surface divergence.

Ans:-High pressure

61. The ………… belt is a region of calms and is also called ITCZ.

Ans:-Doldrum

62. The average location of the doldrums is roughly between ………. 0N and …………

0S.

Ans:-50N and 5

0S

63. The direction of the gradient wind is parallel to the …………..

Ans:-Isobars

64. The wind blows from subtropical high pressure belts toward the equator is known as

…………… winds.

Ans:-Trade

65. The trade winds belt is seen roughly from ……… 0 to …………

0latitude.

Ans:-50, 30

0

66. The surface flow of trade wind is ……….. ward.

Ans:- Equator

67. All the tropical deserts of the world are located between………. and ……….pressure

belts.

Ans:-Subtropical high, Equatorial low

68. The trade winds in the northern hemisphere is known as…………winds.

Ans:-North-east trade

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69. The trade winds in the southern hemisphere is known as……….winds.

Ans:-South-east trade

70. In case of anti-trade winds, the winds flow in the upper atmosphere towards………

Ans:-Pole

71. Anti-trade winds are known as………..

Ans:-Prevailing westerlies

72. ………….. are more variable and intense compared to the trade winds.

Ans:- Prevailing westerlies

73. The atmospheric disturbance in which the air pressure decreases at a particular

location and there is a wind movement towards the center is known as………

Ans:-Cyclone

74. While moving towards higher latitudes, the westerlies become ……….

Ans:- Cooler

75. During a cyclone, the atmospheric pressure is always lowest in the ………… of the

region.

Ans:-Center

76. In the upper atmosphere, the reverse air movement takes place. This circulation is

known as ……… cell.

Ans:-Ferrell

77. In the northern hemisphere during cyclones wind flows in a ……… motion.

Ans:-Anticlockwise

78. Cyclones are also known as ……… or…………

Ans:-Lows, Depressions

79. Cyclones originate and intensify over………..oceans.

Ans:-Tropical

80. Mid latitude lows are known technically as ………….. cyclones.

Ans:- extratropical

81. 1 knot= ………… km/h= ……… m/s.

Ans:-1.85,0.515

82. During low, the wind speed is ……… knots.

Ans:-<17

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83. During depression, the wind speed is ……… knots.

Ans:-17-27

84. During deep depression, the wind speed is ……… knots.

Ans:-28-34

85. During cyclonic storms, the wind speed is ……… knots.

Ans:-35-47

86. During severe cyclonic storms, the wind speed is ………. knots.

Ans:-48-63

87. During hurricanes or typhoons, the wind speed is………knots.

Ans:-64 or higher

88. The center of the cyclone is known as………….of the cyclone.

Ans:-Eye

89. The modern Beaufort system (Beaufort scale) employs a series of numbers from … to

……

Ans:-0,17

90. The anticyclones are associated with………weather.

Ans:-Fine

91. During anticyclone in the northern hemisphere the wind blows in ……… motion.

Ans:-Clockwise

92. Anticyclone travels at a rate appreciably…………. than the typical cyclone.

Ans:-Slower

93. The science of measuring and reading the direction and speed of wind is called……..

Ans:-Anemometry

94. Instruments for surface wind speed measurements are known as………., while those

that make a record are……….

Ans:-Anemometers, Anemograph

95. Devices which measure and record wind direction alone are known as………….

Ans:-Wind vanes

96. Wind is a ………. quantity.

Ans:- Vector

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97. For agrometeorological purposes the observations for wind speed are made at a height

of …… m.

Ans:-3

98. The direction from which the wind comes is known as…………..direction.

Ans:-Windward

99. The direction to which wind blows is known as …………direction.

Ans:-Leeward

100. Generally wind is named by………….direction.

Ans:-Windward

101. Wind direction is expressed in degrees measured clockwise from……………

Ans:-Geographical north

102. Wind direction normally expressed in codes from ……… to ………

Ans:-00, 16

103. Code 00 represents ………

Ans:-Calm


Ans:-Easterly

105. Code 08 represents………..

Ans:-Southerly


Ans:-Westerly


Ans:-Northerly

108. 8 points compass starting from north in a clockwise direction representing

direction from …… 0 to ………

0.

Ans:-340,20

109. Wind vane will have a low moment of …………

Ans:-Inertia

110. The wind speed is measured in ……… or in ………….

Ans:-km/h, m/s

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111. To determine the wind speed at the time of observation take two successive

readings of the anemometer at an interval of …… minutes.

Ans:-3

112. For continuous records, the instruments used are called …………..

Ans:- Anemographs

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Chapter 6. ATMOSPHERIC MOISTURE

1. The moisture content of the atmosphere is about ………… % of all freshwater.

Ans:-0.035

2. The evaporation of 1 kg of water at 200C requires about ……… MJ, which is known as

the ……. of vaporization.

Ans:-2.45, Latent heat

3. Evaporation is a heat …………process.

Ans:-Taking

4. When water condenses in the atmosphere the amount of latent is given is …… MJ, at the

same temperature during evaporation (200C).

Ans:-2.45

5. Condensation is a heat ……… process.

Ans:-Releasing

6. When 1 kg of water freezes, about ……… MJ is released which is referred to as latent

heat of………….

Ans:-0.34, fusion

7. During the ……… process, there is a direct transition of water from the solid to vapour

phase and vice versa without passing through an intermediate liquid phase.

Ans:-Sublimation

8. Sublimation involves the consumption or release of about …… MJ/kg.

Ans:-2.834

9. The distribution of water vapour in the atmosphere is directly related to the distribution of

…………

Ans:-Temperature

10. Water vapour is transferred to the bulk air primarily by ………… or………..

Ans:-Convection, Turbulent transport

11. Atmospheric water vapour………in a non-uniform way from the equator to the poles in

both hemispheres.

Ans:-Decreases

12. Marine air is commonly about ……… % of saturation while continental air, as over

desert may be only ……… % saturated.

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Ans:-80, 20

13. Bulk of the atmosphere’s moisture content contained below …… km.

Ans:-6

14. Increase in water vapour in air =increase in ……………

Ans:-Vapour pressure

15. Saturated vapour pressure is directly proportional to the…………

Ans:-Temperature

16. Below 00C the saturation vapour pressure(SVP) above an ice surface is ………… than

that above a super cooled water surface at the same temperature.

Ans:-Lower

17. Saturated air is moist air whose vapour pressure is equal to the……………….

Ans:-Saturation vapour pressure(SVP)

18. When vapour pressure is ……… than the SVP, air is unsaturated.

Ans:-Less

19. The ratio of the mass of water vapour to the total volume of moist air in which it is

contained is known as……………

Ans:-Absolute humidity

20. SI unit of absolute humidity is……………

Ans:-Kg/m3

21. Molecular weight of water is………….

Ans:-18.016 g/mol

22. The value of the universal constant is……………

Ans:-8.314 KJ/kg/mol/0K

23. The ratio mass of water vapour in a sample of moist air to the total mass of the sample is

known as……………

Ans:-Specific humidity(q)

24. The specific humidity can be expressed in units of…………

Ans:-Kg/Kg

25. The ratio of the mass of water vapour contained in a sample of moist air to the mass of

dry air in the sample is known as………..

Ans:-Mass mixing ratio(W)

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26. The mass mixing ratio is usually expressed in terms of ……………

Ans:-Kg of water vapour/Kg of dry air

27. The ratio of the amount of water vapour in the air to the amount of vapour the air can

hold at that temperature or the capacity is known as ………………

Ans:-Relative humidity(RH)

28. The relative humidity is always expressed in…………..

Ans:-Percentage

29. …………… is the frequently used parameter for the description of humidity conditions.

Ans:-Relative humidity

30. Relative humidity is inversely proportional to………

Ans:-Temperature

31. The temperature at which saturation occurs if air is cooled at constant pressure without

addition or removal of vapour is known as………….

Ans:-Dew point temperature

32. For dew point temperature, the relative humidity is always……………

Ans:-100 percent

33. The difference between the saturation vapour pressure and actual vapour pressure is

known as ………

Ans:-Vapour pressure deficit

34. The drying power of the air is measured by…………

Ans:-Vapour pressure deficit

35. The measurement of humidity in the air is known as………….

Ans:-Hygrometry

36. The instruments used for measurement of humidity are known as…………..

Ans:-Hygrometers

37. Psychrometer consists of 2 thermometers known as …………… &………….

Ans:-Dry bulb thermometer, wet bulb thermometer

38. The difference in ……………. between the wet and dry bulb thermometers is a measure

of relative humidity.

Ans:-Temperature

39. The difference between wet bulb and dry bulb readings is known as…………….

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Ans:-Wet bulb depression

40. For field micrometeorology……………. psychrometer is adapted.

Ans:-Thermocouple

41. To avoid fanning, an instrument called ……………. Psychrometer is used.

Ans:- Sling

42. ……………can be used for the measurement of rapid fluctuation in both temperature and

humidity.

Ans:-Fine-wire thermocouples

43. The sensor of fine wire thermocouple consists of 0.025mm …………….

Ans:-Chromel-constantan thermocouple

44. ………….can be used in correlation studies of heat & vapour transport.

Ans:-Fine-wire thermocouples

45. ………… is widely used for routine measurements and makes a continuous record of

humidity.

Ans:-Hair Hygrometer

46. The sensitive elements of the hair hygrometer are a bundle of ordinary ………….

Ans:-Blond Human Hair

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Chapter 7. CLOUDS, THEIR TYPES & CLASSIFICATION

1. At ……… wavelength the cloudy atmosphere forms an opaque medium.

Ans:-Visible (0.4 to 0.7 µm)

2. Assembly of tiny water and or ice particles in the atmosphere above the earth’s

surface is known as …………

Ans:-Cloud

3. As the air parcel rises, the air pressure upon it……….

Ans:-Decreases

4. The volume and pressure of a gas are inversely proportional as defined

by………..law.

Ans:-Boyle’s

5. …………. law defines that temperature and volume of a gas are directly proportional

to each other.

Ans:-Charle’s

6. As long as the air in a parcel remains unsaturated, temperature will fall at a linear rate

of 0.980C/100m ascent. It is known as……….

Ans:-Dry adiabatic lapse rate (DALR)

7. During condensation heat energy is released in the form of……..

Ans:-Latent heat

8. The lapse rate of temperature within saturated air is known as………..

Ans:-Saturated adiabatic lapse rate (SALR)

9. SALR is always……..than DALR.

Ans:-Less

10. The height at which dew point is reached marks the………….of the cloud base.

Ans:-Lifting condensation Level (LCL)

11. Clouds are formed when moist air cools below a………..

Ans:-Dew point

12. Condensation will not take places if air were completely free of …………..

Ans:-Suspended particles

13. These particles are called as…………….

Ans:-Cloud condensation Nuclei (CCN)

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14. The CCN often made up to………..

Ans:-Common salt of oceanic origin

15. The CCN are …… micrometer to a few micrometers in diameter.

Ans:- 0.1

16. In the presence of the right number of CCN, condensation starts even when RH is as

low as ……

Ans:-75%

17. …………. lifting occurs when an air stream is forced to rise due to an obstacle such

as mountain range or even a city or a large vegetation stand.

Ans:-Orographic

18. ………… uplift occurs when warm air is forced to glide over colder air in frontal

zones.

Ans:-Frontal

19. ……… occurs when air is warmed up by contact with a heated part of the earth’s

surface.

Ans:-Convection

20. ………….. processes are opposite of cloud formation processes.

Ans:- Cloud dissipation

21. The first systematic attempt to classify clouds was made by ………… in the year

…………..

Ans:-Luke Howard, 1803

22. In the year …………the World Meteorological Organization prepared International

Cloud Atlas(ICA).

Ans:-1956

23. ICA describes …….. main cloud types.

Ans:- 10

24. Mean height of high clouds are ……… km.

Ans:-5-13

25. Cirrus is a ……… cloud.

Ans:-High

26. Cirus, cirro cumulus and cirro-stratus are ………… clouds.

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Ans:-High

27. The mean height of medium clouds are ……… km.

Ans:-2-7

28. …………… and ………… are medium clouds.

Ans:-Alto cumulus (Ac), Altostratus (As)

29. The mean height of low clouds are ……… km.

Ans:-<2(below 2)

30. Nimbostratus(Ns), Strato cumulus(Sc), Stratus(St), Cumulus (Cu) and Cumulo-

nimbus(Cb) are ………… clouds.

Ans:-Low

31. ……………are thin feather-like clouds with a fibrous structure and give a silky

appearance.

Ans:-Cirrus clouds

32. ………… clouds are observed detached in the form of filaments, patches or narrow

bands.

Ans:-Cirrus

33. …………clouds show brilliant colours at sunset and sunrise.

Ans:-Cirrus(Ci)

34. Cirrus clouds do not give……………..

Ans:-Precipitation

35. The sun or moon shining through cirrus clouds produces a ……….

Ans:- Halo

36. ……………… clouds appear as a thin whitish layer of very small cloud elements

usually without shadows.

Ans:-Cirro Cumulus(Cc)

37. Cirro-cumulus clouds are mostly arranged in groups, lines or ripples called ….…….

Ans:-Mackerel sky

38. ………. clouds are whitish, transparent covering almost the whole sky and giving it a

milky appearance.

Ans:-Cirro-Stratus(Cs)

39. ……………… clouds produce a halo around the sun and moon.

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Ans:-Cirro-Stratus(Cs)

40. ………. clouds have flattened globular masses of clouds arranged in lines or waves.

Ans:-Alto-Cumulus(Ac)

41. …………… clouds are sometimes referred to as “sheep” clouds or “wool pack”

clouds.

Ans:-Alto-Cumulus(Ac)

42. ……………. clouds are composed of a uniform sheet of cloud of gray or bluish color.

Ans:-Altostratus (As)

43. …………. clouds are like thick Cs.

Ans: -Alto stratus(As)

44. Through Altostratus(As) the sun or moon shines only as a bright spot is known as

…………. phenomena.

Ans:-Corona

45. ………… clouds give a dull overcast sky.

Ans: - Stratus(St)

46. ………….. form a low uniform layer of cloud resembling fog but not resting on the

ground.

Ans:- Stratus(St)

47. ………… clouds continuously produce precipitation.

Ans:-Nimbostratus(Ns)

48. ………….. clouds are dense, shapeless low clouds and horizontally homogeneous.

Ans:-Nimbostratus(Ns)

49. The rain falls from the Nimbo-stratus but does not reach the earth’s surface is known

as …………

Ans:-Virga

50. ………… clouds' upper part is bulging and often resembles a cauliflower.

Ans:-Cumulus (Cu)

51. The flat bases of cumulus clouds indicate the…………..

Ans:-Dew point level

52. Cumulus is generally found in the ………… over land areas.

Ans:-Day time

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53. Most of the cumulus clouds are ………… weather type.

Ans:-Fair

54. …………clouds are heavy, dense masses of clouds with a great vertical development

whose peaks rise like mountains or towers.

Ans:-Cumulo-nimbus(Cb)

55. ……………type of cloud is associated with heavy rainfall, thunder, lightning and

hail.

Ans:-Cumulo-nimbus

56. ……………cloud has an anvil head and flat base.

Ans:-Cumulo-nimbus

57. ……………cloud produces gusty weather.

Ans:-Cumulonimbus

58. The cirro-stratus clouds when able to obscure the outline of the sun they are

called…………..

Ans:-Altostratus

59. Proportion of cloud cover (%) for clear sky is………….

Ans:-0-5%

60. Cloud cover percentage for scattered cloud cover sky is………%.

Ans:-5-55

61. Cloud cover percentage for broken cloud cover sky is…………%.

Ans:-55-95

62. Cloud cover percentage for overcast sky is……….%.

Ans:-95-100

63. ……………sensor of geostationary satellites supply day and night pictures of cloud

cover.

Ans:-Infrared scanning

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Chapter 8. RAINFALL

1. Rainfall is the most predominant form of precipitation in which water droplets of size

greater than …… mm fall on the earth’s surface.

Ans:-0.5

2. The unit of measurement of rainfall is …………

Ans:-mm

3. On an average oceanic air contains ……… million condensation nuclei per litre.

Ans:-1

4. The land air holds ……… million condensation nuclei per litre.

Ans:-5-6

5. Relative humidity air > Relative humidity of ………… >Relative humidity of

………..

Ans:-Ice, water surface

6. The major source for freezing nuclei are…………….

Ans:-very fine soil particles

7. Different hexagonal forms of crystal developing at different………..ranges.

Ans:-Temperature

8. Ice crystals generally have ……… shape.

Ans:-Dendritic(Branched)

9. Bergeron-Findeisen theory is not completely satisfactory for …………clouds.

Ans:-Warm

10. ………… encourages collisions in the early stages in cumulus form clouds.

Ans:-Turbulence

11. Mixed snow and rain is called as……………

Ans:-Sleet

12. Sleet is especially likely when air temperature at the surface is about …… 0C.

Ans:-1.5(34-350F)

13. Snow rarely occurs when air temperature exceeds …… 0C.

Ans:-4(390F)

14. Opaque ice is known as ………

Ans:-Rime

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15. Soft hail pellets are generally of ………… shape.

Ans:- spherical

16. Soft opaque ice pellets are quite common in winter and spring from ………. Clouds.

Ans:- Cumulonimbus

17. Clear ice is also called……..

Ans:-Glaze

18. Rainfall intensity=…………….

Ans:-Amount of rainfall (cm)/Duration of rainfall (hr)

19. According to the primary mode of upliftment of the air there are ……… main types

of precipitation.

Ans:-3

20. On occasions, hailstorms may reach giant size, weighing upto …… kg each.

Ans:- 0.76

21. ………… type of precipitation is associated with towering cumulus and

cumulonimbus clouds.

Ans:-Convective

22. There are …………… subtypes of convective precipitation.

Ans:- 3

23. Cyclonic type precipitation moves usually…………. in the westerly wind belt.

Ans:-Eastward

24. …………… depressions give moderate and generally continuous precipitation over

very extensive areas.

Ans:- extratropical

25. In mid latitudes orographic effects tend to increase the frequency and intensity of

……….. precipitation.

Ans:- Winter

26. ………type of precipitation depends upon the size of the barrier.

Ans:-Orographic

27. When a parcel of air is either warmer than the air surrounding it or is actively

undercut by colder encroaching air give rise to…………

Ans:-Thunderstorm

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28. As condensation begins to form clouds droplets, ………… is released.

Ans:- Latent heat

29. The temperature of air and earth surface decreases to such an extent that water

condenses over the surface, it is called as……….

Ans:-Dew

30. …………… is the water that is condensed onto the ground, rocks, grass and so on.

Ans:- Dew

31. Dew occurs in ………hours.

Ans:-Early morning

32. Dew generally forms at night due to …………….

Ans:- Radiational cooling

33. Dew forms in ………..nights.

Ans:-Clear, still, cool

34. Dew is especially effective when the ground layer of air has a high………..

Ans:-Relative humidity

35. …………is the only form of moisture available to plants and animals in extreme

deserts.

Ans:-Dew

36. …………… is the temperature at which saturation of the air occurs.

Ans:-Dew point

37. At dew point temperature, SVP=………

Ans:-AVP

38. If the parcel of air is hypothetically held at a constant pressure and vapour content,

the temperature at which it must be cooled to reach saturation is called its……….

Ans:-Dew point

39. The temperature of air decreased to such an extent that water droplets remain

suspended in air but do not deposit over the surface and are called as……….

Ans:-Fog

40. Fog occurs in …………. hours.

Ans:- Early morning

41. Fog is a …………. cloud that lies on, or very close to the surface of the earth.

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Ans:-Stratus

42. Horizontal visibility in fog is reduced to ……… km.

Ans:-<1

43. Fog is an aggregate of very small water droplets in a size range of ……µm.

Ans:-10-50

44. These water droplets are typically in concentrations of ……….. per cc.

Ans:- 10-100

45. Expansion cooling due to ascent of air mass may lead to formation of……………..

Ans:-Fog

46. ………. produces a thin, grayish veil over a land shape, reducing visibility to a lesser

extent than fog.

Ans:-Mist

47. Mist particles range in size from …… to……. µm.

Ans:-50-500

48. ………… is intermediate between damp haze and fog.

Ans:- Mist

49. The temperature of the air and earth surface decreases to such an extent that water

condenses and freezes over the surface of deposition is called as……….

Ans:-Frost

50. ………… is a solid phase of water.

Ans:- Frost

51. For white or hoar frost to occur the surfaces on which the frost form must be

………… 0C or below.

Ans:-0

52. The hoar implies ……… tone.

Ans:- Gray or grayish

53. The loss of heat to or below the freezing level by the atmosphere and surface objects

in dry air and without reaching saturation creates ………. frost.

Ans:-Black

54. Hail is a type of precipitation often composed of alternating clear and opaque ice,

having a diameter upto …… µm.

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Ans:-50 or more

55. There are ……… forms of hail.

Ans:- 3

56. ……… hail composed of loosely compacted ice crystals and is roughly spherical

tending to fracture upon striking the ground.

Ans:- Graupel or soft

57. Ice crystals from graupel hail have a diameter less than ……… mm.

Ans:-5

58. ……… hail is semi-transparent.

Ans:-Small

59. Hail stone from ………… hail when strikes' hard surface remain intact.

Ans:-Small

60. ……… hail is composed of hail stones greater than 5mm.

Ans:-True or severe

61. ……….. is the form of precipitation in which small balls of ice with diameter 5.5 µm

or sometimes more falls.

Ans:- Hail

62. …………is the form of precipitation in which drops are of diameter 0.5µm and very

close to each other.

Ans:-Drizzle

63. ……… is the form of precipitation in which drops are of diameter 0.5 µm or more.

Ans:-Rain

64. ………… is the form of precipitation in which loose aggregate of branched ice

crystal fall.

Ans:-Snow

65. A day is called a rainy day when rainfall recorded is more than or equal to …… mm.

Ans:-2.5

66. The rainfall is measured by an instrument known as ……………

Ans:-Rain Gauge

67. There are ……….. types of rain gauges.

Ans:- 2

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68. Collector of ordinary rain gauge having area of ………… sq cm.

Ans:-100-200

69. ……… gives continuous records of the rainfall.

Ans:- Self-recording rain gauge

70. Both the collector and the base of ordinary rain gauge are made up of……………….

Ans:-Fiber glass reinforced polyester (FRP)

71. Generally, in an ordinary rain gauge at a time we can measure………mm of rainfall.

Ans:-20

72. The Indian summer monsoon is also known as ……….. monsoon.

Ans:-South-West

73. The south-west monsoon contributes about ………… % to the annual rain water

potential.

Ans:-80

74. The annual average precipitation of India is …………… mm.

Ans:-1083(World bank data, 2014)

75. The terms monsoon appears to have originated from the Arabic word……which

means season.

Ans:-Mausim

76. Differential heating of land and ocean leads to……………….

Ans:-Monsoon circulation

77. ………… formulated four simultaneous criteria to indicate exact positions of the

monsoon areas.

Ans:- Ramage(1971)

78. The normal dates of onset of monsoon over the Indian subcontinent have been

determined from the average ………data.

Ans:-Pentad

79. The onset of summer monsoon takes place over the mainland of India by………….

Ans:-1st June

80. ……..is known as the gateway of Indian monsoon.

Ans:-Kerala

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81. Over north India, monsoon generally advances from ……… to ……… direction

along with monsoon easterlies.

Ans:-East, West

82. Monsoon easterlies are also known as …………

Ans:-Bay current

83. The summer monsoon is withdrawn from the whole country except the south

peninsula by……

Ans:- 15 October

84. During south west (summer) monsoon ………… receive highest rainfall.

Ans:- Coastal Karnataka(250-350 cm)

85. The onset of northeast monsoon normally takes place over the south peninsula at

about…………

Ans:-15 October

86. The highest seasonal rainfall during north east monsoon received by………. state.

Ans:-Tamilnadu

87. ………… mm of rainfall received by Tamilnadu during north east monsoon.

Ans;-600-800

88. ……….. affects India weather during December to march.

Ans:-Western disturbances

89. ………..is defined as a low or a trough of low pressure at the surface.

Ans:-Western disturbances

90. Time scale for short range weather prediction is ……. days.

Ans:-1-3

91. Time scale for medium range weather forecasting is ……… days.

Ans:-4-10

92. Time scale for long range weather forecasting is………… days and up to a season.

Ans:-Beyond 10

93. …………… method is based on mathematical equations simulating the physics of the

global atmosphere.

Ans:-Dynamical

94. ………..method is based on empirical and statistical formulation.

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Ans:-Statistical

95. Most of the LRF techniques evolved are …………….

Ans:- Statistical

96. Monsoon is a …………. system.

Ans:- Complex

97. DSTM Stands for………….

Ans:-Dynamic Stochastic Transfer Model

98. The first operational LRF was issued by IMD in……….

Ans:-June, 1886

99. Landmark contributions in the field of LRF were made by…………….

Ans:-Sir Gilbert Walker(Director General, IMD [1904-1924])

100. PPRM stands for………………

Ans:-Parametric and power regression model

101. PPRM, a new LRF model was developed in the year………….

Ans:-1988

102. PPRM was developed by IMD scientists led by………..

Ans:-Dr.V.R. Gowarikar

103. PPRM uses ……… regional and global land-ocean-atmosphere parameters.

Ans:-16

104. PPRM parameters are physically related to the …………….

Ans:- Indian Monsoon rainfall

105. Based upon an observed variability in space and time, for the country as a whole

season rainfall within …… % of the long period average is defined as normal.

Ans:-10

106. For individual meteorological subdivisions rainfall within ……… % of the long

period average is defined as normal.

Ans:-19

107. ……… model utilizes the signals from 16 antecedent global and regional land-

ocean-atmospheric parameters.

Ans:-Parametric

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108. ………… model is based on the physical relationship of monsoon rainfall with 16

different individual parameters.

Ans:-Power regression

109. ………… model is based on statistical correlation between monsoon rainfall and

certain global and regional meteorological parameters.

Ans:-Multiple regression

110. Multiple regression models utilizes …… predictors.

Ans:- 7

111. …….. model considers the atmosphere as a dynamic system.

Ans:-DSTM

112. ………… utilizes regional parameters as inputs and yields monsoon rainfall over

the country as a whole as an output.

Ans:-DSTM

113. ……..model has been developed based on dynamic stochastic transfer and power

regression technique.

Ans:-Power transfer

114. Power transfer models use………. regional and global parameters as inputs.

Ans:-12

115. …….. model has been developed based on the Empirical Orthogonal Function

(EOF) analysis technique and makes use of 8 regional and global parameters.

Ans:-Principal component regression

116. Hybrid artificial neural network models are different from principal component

regression models by using …………….

Ans:-Artificial neural network techniques

117. The performance of ……… and ………… model proves to be most accurate.

Ans:-Parametric, power regression

118. The ………… forecasting of monsoon is most essential in planning the crop and

agriculture in developing countries.

Ans:-Long range

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Chapter 9. SOIL MOISTURE

1. ISSS stands for …………..

Ans:-International Soil Science Society

2. Particle diameter of gravel is ………… mm.

Ans:->2

3. Particle diameter of coarse sand is …… mm.

Ans:-0.2 to 0.2

4. Particle diameter of fine sand is…..mm.

Ans:-0.02 to 0.2

5. Particle diameter of silt is ……… mm.

Ans:-0.002 to 0.02 mm

6. Particle diameter of clay is ……… mm.

Ans:-<0.002

7. The relative proportion of sand, silt and clay determines the ……………

Ans:-Soil texture

8. The term ………… is an expression of the predominant size or size range of the particles.

Ans:- Soil texture

9. The arrangement of individual soil particles with respect to each other into a pattern is

called………..

Ans:-Soil structure

10. The ratio of mass of dried particles to the total volume of soil is known as…………..

Ans:-Dry bulk density

11. The ratio of mass of moist soil per unit volume is called as……….

Ans:-Wet bulk density

12. The ratio of the volume of pores(voids) to the total soil volume is known as……...

Ans:-Porosity(n)

13. The ratio of the volume of pores to the volume of solids is terms as ……………

Ans:-Void ratio(e)

14. Void ratio is also known as……………….

Ans:-Relative porosity

15. The term ………… refers to the relative water content in the soil.

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Ans:-Soil wetness

16. The ratio of mass of water to the soil is known as………….

Ans:-Mass wetness(w)

17. Mass wetness is often referred to as the ………………

Ans:-Gravimetric water content

18. Mass wetness is also commonly called as…………..

Ans:-Soil moisture content

19. Mass wetness is expressed in ……………….

Ans:-Percentage

20. The ratio of volume of water to the total soil volume is called as…………..

Ans:-Volume wetness(θ)

21. Volume wetness is also called as ………………… of the soil.

Ans:-Volumetric water content

22. ……………refers to the volume of water present in the total pore volume.

Ans:-Degree of saturation

23. Water is held in the soil by ……….. and ………. forces.

Ans:- Adhesive, Cohesive

24. Water held tightly to the surface of soil particles by adsorption force is known as

…………

Ans:-Hygroscopic water

25. Hygroscopic water is also known as…………

Ans:-Water of adhesion

26. Water held by force of surface tension and continuous films around soil particles and in

the capillary spaces is known as………………

Ans:-Capillary water

27. Capillary water is also known as water of…………….

Ans:-Cohesion

28. ………….water moves freely in response to gravity and drains out of the soil.

Ans:-Gravitational

29. ………… water is not available to plants.

Ans:-Hygroscopic

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30. The gravitational water is held in the soil at tension of…………atm or less.

Ans:-1/3 (One third)

31. Capillary water is held in the soil at tension between ……… and ………atm.

Ans:-1/3,31

32. Between ……….and ………… atm, the movement of capillary water is very sluggish.

Ans:-15,31

33. Water at the tension beyond ………… atm is not available to the plants.

Ans:-15

34. One atmosphere= …………… cm of water column=………..cm of mercury column.

Ans:-1036,76.39

35. Kinetic energy for movement of water in the soil is………..

Ans:-Negligible

36. Kinetic energy is proportional to the……………..

Ans:-Square of velocity(v2)

37. Differences in a ………… of water between one point and another give rise to the

tendency of water to flow within the soil.

Ans:-Potential energy

38. Soil water moves from the zone of……….. potential energy to the zone of ………

potential energy.

Ans:-Higher, lower

39. Soli water moves constantly in the direction of………..potential energy.

Ans:-Decreasing

40. For saturated soils, the ………… pressure is greater than the atmospheric pressure.

Ans:-Hydrostatic

41. Soil water potential is…………for saturated soil.

Ans:-Positive

42. For unsaturated soils the water is constrained by……… and ………..force.

Ans:-Capillary, adsorptive

43. Energy potential for unsaturated soil is ………….

Ans:-Negative

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44. In a saturated soil, the hydrostatic pressure and suction or tension are…………

Ans:-Zero

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CHAPTER 10. WEATHER IN THE INCIDENCE OF PESTS DISEASES

1. A high humid temperature encourages development of ……………fungi, which check insect

population.

Ans: Entomophagous

2. High infestations of stem borer noted in paddy planted from……… to…..............

Ans: October, January

3. The stem borer infestation is negatively correlated with…………… and ............ and ………….

Ans: Rainfall, Minimum temperature, Humidity

4. The moths of stem borer are active between the temperature range of …………to……….0C.

Ans: 19, 33

5. The maximum number of eggs by stem borer are laid at…………0C & ……% RH.

Ans: 29-30, 90

6. Infestation by rice gall midge requires temperature ranges between………… to………0C.

Ans:-19.8oC, 35.2

oC

7. …………% of RH is favorable for rice gall midge infestation.

Ans: 89, 94

8. ………to………mm of mean rainfall is favorable for rice gall midge infestation.

Ans: 4.5-62.5

9. High humidity, less SSH high temperature is…………for rice gall midge infestation.

Ans: Favorable

10. Temperature range of……… to………0C is conductive for brown plant hopper attack.

Ans: 21-23

11. ………….mm rainfall per week for at least 2 weeks is conductive for brown plant hopper

attack.

Ans: 30

12. Temperature range of…………to………0C is favorable for rice swarming caterpillar attack.

Ans: 22, 32

13. Relative humidity between …………to……….% is favorable for rice swarming caterpillars

infestation.

Ans: 65, 70

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14. The dry warm weather during the hatching & molting phase favors the multiplication

of…………pest.

Ans: Rice grasshopper

15. Jowar shoot fly requires…………0C &…………%RH for egg laying & larval activity.

Ans: 30-40, 40-75

16. High relative humidity of……………% is not favorable for infestations of Jowar shoot fly.

Ans: 86-90

17. …………% of RH is required for lower mute infestation

Ans: 51

18. During…………stage the infestation by cotton spotted bollworm occurs at a rapid rate.

Ans: Boll formation

19. ……………. % of RH, BSS of…………hr & weekly rainfall of…………mm is favorable for

cotton spotted bollworm infestation

Ans: 95-100, 5-7, 17-210

20. For more larval activities of cotton bollworm the Tmin is………0C &………Tmax is……….

0C.

Ans: 19-20, 30-32

21. Tmax of…………0C & Tmin of…………

0C is favorable for sugarcane shoot borer.

Ans: 37.8-41.4, 24.4-31.1

22. Temperature …………0C and annual rainfall of ………mm is favorable for development of

Colorado potato beetles.

Ans: 16-27, 600-1500

23. …………0C of temperature is lethal for larvae of Colorado potato beetles.

Ans: 38

24. Egg laying by Colorado potato beetle is maximum at………0C & mortality Occurs at……

0C.

Ans: 25, 30

25. Beetles go for hibernation when temperature falls below…………….0C and can tolerate lowest

temperature up to………..0C.

Ans: 12, -4

26. ETL stands for…………………

Ans: Economic Threshold Level

27. Rice blast disease is a…………….. disease.

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Ans: Fungal

28. Temperature of around………. 0C during night and day for about………...hr is found to be

suitable for infection of rice by rice blast disease (Pyricularia oryzae)

Ans: 20, 14

29. The fungus (Pyricularia oryzae) in the rice leaves grows most rapidly at ………0C.

Ans: 24-28

30. ……….inhibits the development of the blast fungus and the spores do not germinate

in……….

Ans: Sunshine, direct sunlight

31. A combination of……….weather, dull……….days and temperature of……….0C are suitable

for development of bacterial blight of rice.

Ans: Rainy, windy, 22-26

32. Crops supplied with high doses of…………shows more disease incidence by bacterial

blight.

Ans: Nitrogen

33. The optimum temperature for the germination condition of the brown spot is between

……………0C & fictions occurs when humidity is……% or more.

Ans: 25-30, 90

34. Brown spot of rice is a………….disease.

Ans: Fungal

35. Spread of fungus of brown spot disease inside the host is reported to be greater is………….

Ans: Darkness

36. Most susceptible stage of the crop for brown spot disease is ………stage.

Ans: Flowering

37. ………..days appear to be favorable for the brown spot disease.

Ans: Cloudy

38. Warm conditions with temperature more than …….0C and light rain favors incidence of

brown rust disease in wheat.

Ans: 20

39. Fungus of loose smut germinates at………….0C.

Ans: 18-20

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40. Heavy incidence of loose smut noticed at temperature of……….0C.

Ans: 20

41. Karnal bunt of wheat is an……….borne disease.

Ans: Air

42. Karnal bunt of wheat becomes epiphytotic when there is ……… rain and the soil

temperature is around………0C.

Ans: Heavy, 15-20

43. The optimum temperature for both production and germination of conidia of downy mildew

disease (Sclerophthora) is about……….0C.

Ans: 25

44. Tikka Disease of groundnut requires relative humidity of about……….% and temperature

around…....0C during the growing period of groundnut.

Ans: 90, 20

45. Average maximum temperature of……0C and average minimum temperature of ..…..

0C and

Monthly rainfall of………mm are found to be favorable for outbreak of tikka disease.

Ans: 33, 20, 88

46. For outbreak of late blight of potato, a minimum of…………hrs of dew in the night is

suitable.

Ans: 4

47. Minimum temperature during night required for the outbreak of potato blight is

below………0C.

Ans: 10

48. The optimum temperature for spore germination of sugarcane spots is about…….0C.

Ans: 25-30

49. The spores are killed instantaneously at………0C, but they survive for more than……..days.

Ans: 62, 3

50. For spore germination……….% humidity is essential.

Ans: 100

51. Apple scab is caused by………

Ans: Fungus.

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52. The optimum temperature for germination of spores of Downy mildew of grapevine

is……….0C with the minimum of ………

0C.

Ans: 10-16, 5

53. Alternaria blight of cucurbits is severe during……….season.

Ans: Kharif

54. Alternaria blight of cucurbits inhibits by……….temperature.

Ans: Low

55. The spore germination of Alternaria blight of cucurbits requires RH above…….% and are

optimum between…….. and …….0C.

Ans: 85, 25 & 28

56. A minimum period of nearly ………hour of very high RH is required for successful

infection by Alternaria blight.

Ans: 48

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CHAPTER 11. DROUGHT

1. ………… is universally acknowledged as a phenomenon associated with scarcity of water.

Ans: Drought

2. ………….drought occurs when there is a prolonged absence or marked deficiency or poor

distribution of precipitation over an area.

Ans: Meteorological

3. Meteorological drought over an area according to IMD is defined as a situation where seasonal

rainfall over an area is less than……..% of its long term average value.

Ans: 75

4. Moderate drought occurs when rainfall deficit is between……….to ……….%.

Ans: 26, 50

5. Severe drought occurs when rainfall deficit exceeds……..% of the normal.

Ans: 50

6. There are………drought years since 1875.

Ans: 25

7. ……..drought occurs when the surface & ground water resources are too insufficient to meet the

demand.

Ans: Hydrological

8. …………drought occurs when available soil moisture is insufficient for healthy crop growth and

causes extreme stress & witting.

Ans: Agricultural

9. …………drought occurs in association with the delay in commencement of sowing rains.

Ans: Early season

10. ………drought occurs in association with the breaks of the south west monsoon.

Ans: Mid season

11. ……drought occurs when the rainfall in the region may be adequate for one crop but may not be

for others.

Ans: Apparent

12. Low humidity & hot dry desiccating winds causes…………..

Ans: Atmospheric Drought

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13. Kilting causes due to………drought.

Ans: Atmospheric

14. Persistent drought for years leads to………..

Ans: Aridity

15. ……….is a permanent climate situation of a region.

Ans: Aridity

16. ……….is a temporary phenomenon and often occurs when rainfall of a region is below normal.

Ans: Drought

17. Increasing atmospheric turbidity and house warming are the causes of ……..drought.

Ans. Sahelian

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CHAPTER 12. WEATHER FORECASTING

1. Weather forecasting for agriculture is divided into ………..groups.

Ans: Four

2. ………. ranges from a few hours to one day.

Ans: Now casting

3. Short range forecasts range from……hours to less than…….Days.

Ans: 24, 3

4. Short range forecasting in a forecast & warning of weather elements hazardous to

agriculture are valid for……….hours to two days.

Ans: 36

5. The short range forecast is issued …….a day based on synoptic conditions.

Ans: twice

6. Medium range forecasting is valid for………. to……….days.

Ans: 3, 10

7. NCMRWF stands for……………..

Ans: National centre for medium range weather forecasting

8. NCMRWF established during………. in New Delhi.

Ans: 1988

9. Long range forecasting is the forecast for more than……….. days.

Ans: 10

10. ……released in air for measurement of wind direction & speed at different heights in the

atmosphere using a theodolite.

Ans: Pilot balloons

11. ………is an optical telescope.

Ans: Theodolite

12. ………is a combination of barograph, thermograph & hygrograph.

Ans: Meteorograph

13. ……………Provides data immediately which are useful for weather forecasting.

Ans: Radiosonde

14. Radar stands for……………….

Ans: Radio detection and ranging

15. ………..is an Indian satellite which gives information on cloud spread, amount &

information on temperature of the earth’s surface and cloud tops.

Ans:-INSAT-IA

16. AMFU stands for…………..

Ans: Agro meteorological field units

17. ARIMA models based on…………..global land ocean atmosphere variable.

Ans: 16

18. ARIMA stands for………………………….

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Ans: Auto Regressive Integrated Moving Average

19. IMD issuing FWBs since…………………..

Ans: 1945

20. FWB stands for …………

Ans: Farmers weather Bulletins

21. FWB contains forecast of expected weather for the next………hrs

Ans: 36

22. AAS Stands for…………..

Ans: Agro meteorological Advisory services

23. AAS is in operation since………….

Ans: 1977

24. AAS based on …………range weather forecasting.

Ans: Medium

25. NCMRWF has proposed to establish…………AMFUs.

Ans:-127

26. The ……………prepares AAS bulletins.

Ans:-AMFU

27. The NCMRWF provides information on MRF every……… and ………

Ans: Tuesday, Friday

28. AASU stands for…………..

Ans: Agro met Advisory units

29. SMCS Stands for……….

Ans: State meteorological centres

30. …………..refers to an abnormal increase of sea surface temperature over central and

eastern parts of the equatorial pacific ocean of the coast of Peru.

Ans: El-Nino

31. ….. was globally the warmest year.

Ans: 1997

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CHAPTER 13. REMOTE SENSING

1. Remote sensing deals with the use of………..

Ans: Electromagnetic Radiation

2. According to planck's law the radiation emitted by Earth is………0K.

Ans: 300

3. According to planck's law the radiation emitted by the sun is……….0K.

Ans: 6000

4. Rockets can be used to carry remote sensing payloads to great height up to……km.

Ans: 1000

5. Geostationary orbit is…………km above the earth.

Ans: 36,000

6. Near earth orbit is also known as……..orbit.

Ans: Polar

7. When chlorophyll absorption decreases the red reflectance……….

Ans: Increases

8. As moisture content in the soil increases the reflectance in the optional IR region……….

Ans: Decreases

9. In a thermal IR image moist soils look ………compared to the dry soils.

Ans: Darker

10. Water absorbs most of the radiations in the………. and ……….regions.

Ans: NIR, MIR

11. …………in water generally leads to an increase in the reflectance.

Ans: Turbidity

12. The reflectance peak shifts towards………..wavelength.

Ans: Longer

13. Snow has very high reflectance up to………cm.

Ans: 0.8

14. In case of clouds there is …………scattering which makes them appear uniform bright

throughout the range of 0.3 to 3 cm.

Ans: Non selective

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CHAPTER 14. CROP MODELLING AND IT’S APPLICATION

1. …………is an equation or set of equations which represent the behavior of a system.

Ans: Model

2. …….models express the relationship between yield or yield component & weather

parameters.

Ans: Statistical empirical models

3. …………model explains the mechanism of influencing dependent variables i.e.,

photosynthesis, LAI etc.

Ans: Mechanistic

4. ………..models estimate/predict the exact value of the yield or dependent variable.

Ans: Deterministic

5. …….….models are developed by mathematical techniques and wave well defined

coefficients.

Ans: Deterministic

6. ……… models use the value of the weather parameter at some or the other

probability level.

Ans: Stochastic

7. …………models do not account for time factors.

Ans: Static

8. ……….. models are defined at a given time.

Ans: Dynamic

9. CERES Stands for…………

Ans: Crop Environment Resource Synthesis model

10. CERES was developed by………in 1994.

Ans: Ritchie et. al

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CHAPTER 15. KEY TAKEDOWNS

A. CLIMATE NORMALS FOR CROP PLANTS

RICE (Oryza sativa)

High temperature, high RH, ample water

⮚ Mean temperature=220C in the entire growing period.

⮚ If night temperature falls below 150C, yield reduces (during entire vegetative plants).

⮚ The period during which low temperature is most critical is about 10 to 14 days before

heading.

⮚ For getting higher grain yield a solar radiation of 300 cal/m2 per day is required.

⮚ For low land rice=200 mm rainfall/month

⮚ For upland rice=100 mm rainfall/month

⮚ At a waxy ripening stage no standing water in the field is required.

WHEAT (Triticum spp.)

⮚ It withstands extreme cold conditions.

⮚ Optimum temperature is 15-200C

⮚ High temperature during growth and tillering adversely affects the crop.

⮚ Bright sunny days with dryness and colder nights during ripening periods give better

sized quality grains.

⮚ Optimum rainfall requirement during the growing season -50-87.5cm.

⮚ Total water requirement-35-55cm

⮚ Daily consumptive use-0.17-0.87cm

MAIZE (Zea mays)

Warm and Humid region crop.

⮚ Mean temperature is 240C and night temperature above 15

0C.

⮚ No maize cultivation is possible in areas where the mean summer temperature is below

190C & night temperature falls below 21

0C during summer months.

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⮚ High night temperature results in less yield.

⮚ If the temperature is around 350C during flowering period, the yield will be poor.

⮚ 50-25 cm of rainfall during life span.

COTTON (Gossypium Spp.)

Subtropical climate (Heat loving)

⮚ Cool night & low day time temperature encourage vegetative growth.

⮚ Mean temperature is 160C (Above 39

0C is detrimental)

⮚ Low night temperature during ball development period results in shorter fiber and bad

boll opening.

⮚ T range=25.300C

⮚ Rainfall =50-65 cm

⮚ Peak daily water use rate=0.35 inch

SUGARCANE (Sacharum spp.)

Tropical crops (Warm humid climate)

⮚ For good sprouting, Mean daily temperature is 220C (30

0C is best)

⮚ Soil temperature of 27-280C is optimum for the plant growth.

⮚ Maximum temperature above 370C inhibits growth.

⮚ RH above 70%, moist humid climate & 20-320C of temperature, short day, long night

and water supply highly conductive for good vegetative growth.

⮚ If sunshine is cut down to half then crop yield is also cut down to half.

⮚ Very low temperature reduces the quality of juice.

⮚ 125-165 cm rainfall in a year.

POTATO (Solanum tuberosum)

Temperate Climate

⮚ Optimum temperature at planting time is 18-200C.

⮚ Too high temperature damages the tubers and low temperature damages the sprouting.

⮚ Decrease in tuber formation at 250C and complete inhibition at 29

0C.

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⮚ Plants get damaged by mild frost.

⮚ 40-60cm rainfall is required

⮚ The crop is moderately sensitive to salinity.

TOBACCO (Nicotiana spp.)

Tropical plant

⮚ Temperature range =10-320C.

⮚ Temperature>350C results in leaf burning.

⮚ Optimum Temperature=24-270C.

⮚ Low temperature is essential for germination.

⮚ Warm moist weather for growth and cool dry weather for ripening.

⮚ High humidity during leaf curing is necessary.

⮚ 80-100cm rainfall is required.

GRAM (Cicer arietinum)

Cool & humid climate

⮚ Crop can germinate from temperature 10 to 450C.

⮚ Optimum Temperature =15-200C.

⮚ Root zone soil temperature=15-250C.

⮚ Nodulation is adversely affected when the root temperature exceeds 300C.

⮚ Excessive rains after sowing and at flowering are harmful.

⮚ Excessive humidity also has a negative influence on new settings.

⮚ Highest food formation records at RH from 20-40%.

SOYABEAN (Glycine max)

Warm, humid climate semi tropic

⮚ Optimum temperature for its seed germination is 300C.

⮚ High temperature during flowering and ripening increases fat but reduces proteins.

⮚ Soil temperature affects the nodulation and nitrogen fixation.

⮚ Growth is limited by temperature in excess of 330C.

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⮚ 45-75 cm rain is required per season.

⮚ Moisture stress during pod filling period leads to 20-50% reduction in grain yield.

GROUND NUT (Arachis hypogaea)

Warm and moderately moist climate

⮚ Warm climate (24-340C) plenty of sunshine is highly favorable for crops.

⮚ Temperatures above 440 C and below 4

0C are not desirable.

⮚ Optimum seed germination temperature is 14-160C.

⮚ The maximum number of pods have been harvested at mean soil temperature of 230C.

⮚ The number of pod decreases when soil temperature increases

⮚ 50-70 cm rainfall

⮚ Rain at maturity reduces yield.

MUSTARD (Brasica juncea)

Subtropical, temperate climate

⮚ 10-15cm rainfall during crop growth is best.

⮚ Cool temperature with good moisture during the crop growing period and dry harvest

period is ideal for crop.

SUNFLOWER (Helianthus annuus)

cool, temperate region

⮚ High daily temperature decreases the number and weight of seed per plant, seed yield and

oil content.

⮚ Optimum temperature =18-250C.

⮚ High RH marked positive influence on growth of the crop.

⮚ 300-550 mm of water requirement

⮚ Tolerant to frost and salt.

B. WEATHER IN THE INCIDENCE OF PESTS AND DISEASES

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SOME PESTS:-

RICE STEM BORER

⮚ High infestation in rice:-October to January

⮚ Low infestation in rice:-June to October

⮚ Infestation is negatively correlated with rainfall, minimum temperature, humidity and

positively with maximum temperature.

⮚ Moths are active between the temperature range of 19-330 C.

⮚ Maximum number of eggs laid at 29-300 C and 90% RH.

RICE GALL MIDGE

Favorable conditions for infestation

⮚ Tmin=19.80 C

⮚ Tmax=35.20 C

⮚ RH=89.94%

⮚ Mean rainfall =4.5 to 62.5mm per 5 days.

⮚ High humidity, less SSH and high temperature are conductive.

BROWN PLANT HOPPER

Tmin=21-230 C,30mm heavy precipitation per week for 2 weeks during September is

conducive for attack.

RICE SWARMING CATERPILLAR

⮚ 2-3 weeks of dry spells.

⮚ Trange=22-320C, RH=65-70% & SSH of 7-9 hrs is favorable.

RICE GRASSHOPPER

Dry and warm weather during hatching is favorable.

JOWAR SHOOT FLY

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Tmax of 30-400 C & RH 40-70% is conducive for egg laying and larval acting. Whereas, a

very high RH of 86-90% is not favorable for infestation.

JOWAR MITE

Tmax=34.5-38.80C, Tmin=24.4-25.5

0 C, RH=51%

COTTON SPOTTED BOLLWORM

⮚ July/August- Infestation occurs at rapid rate(Boll formation)

⮚ RH=95-100%, BSS of 5-7 hrs, Rainfall of 17-210 mm is favorable infestation.

⮚ During Oct/Nov the larval activity is more when Tmin ranging between 19-200C & Tmax is

30-320C.

SUGARCANE SHOOT BORER

⮚ Tmax=37.8-41.40C, Tmin=24.4-31.1

0C

⮚ RH-I=23-73% and RH-II=16.61%

COLORADO POTATO BEETLE

⮚ Trange=16-270C, Rainfall=600-500 mm (Annual)

⮚ Egg laying maximum at 250C and mortality at 30

0C.

⮚ Incubation period is 5 days at 300C and 19 days at 12

0C.

⮚ 380C is lethal for larvae.

⮚ <120C=Hibernation Tolerate up to 4

0C.

DISEASES

RICE BLAST DISEASE (Pyricularia oryzae)

⮚ Fungal Disease.

⮚ 200C (Night), day temperature of 30

0C with a day light for 14hrs have been found

favorable.

⮚ The fungus invades the rice leaves most rapidly at 24-280C.

⮚ RH of 92% and above and free water is required for conidial germination and infection

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⮚ Sunlight inhibits the development of blast fungus.

⮚ Cloudy overcast weather encourages blast spread.

⮚ Peak conc. of spore dispersal occurs around 4am favored by night temperature of 25-

270C and humidity of 86-98%.

BACTERIAL BLIGHT OF RICE

⮚ Rainy weather, dull windy days, T of 22-260C are favorable.

⮚ Plants in shade, closely planted, supplied with high doses of nitrogen shows more disease

incidence.

BROWN SPOT OF RICE

⮚ Optimum temperature germination of Conidia is 25-300C.

⮚ Infection occurs when humidity is 90% or more.

⮚ Spread of fungus inside the host is greater in darkness.

⮚ Most susceptible stage is the flowering stage.

⮚ South west and northeast monsoon, cloudy day is favorable for disease.

BROWN RUST OF WHEAT

Temperatures more than 200C and light rain favors disease incidence.

LOOSE SMUT OF WHEAT

⮚ Fungus germinates at 18-200C.

⮚ Moderate attack at 190C and heavy at 20

0C.

KARNAL BUNT OF WHEAT

Air borne disease

⮚ Heavy rain, soil temperature around 15-200C, 2 to 3 weeks prior to flowering is

favorable.

⮚ Low temperature favors spore germination.

DOWNY MILDEW OF MAIZE

⮚ Optimum temperature =250C for production and germination of conidia.

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⮚ Conidia are not produced below 130C and above 31

0C, germination occurs at 10

0C to

340C.

⮚ Fresh water is required for germination.

TIKKA DISEASE

⮚ If there is enough precipitation with RH of 90%, temperature around 200C for 6-7 days

during growing period of groundnut, the onset of disease can be predicted.

⮚ Tmax of 330C, Tmin of 20

0C and monthly rainfall of 88 mm is found to be favorable for the

outbreak.

LATE BLIGHT OF POTATO

⮚ 4 hrs of dew during night.

⮚ Minimum temperature of night below 100C.

⮚ Rainfall of at least 0.1 mm in 24 hrs followed by dew at night.

SUGARCANE SMUT

⮚ Spore germination =25-300C (Optimum)

⮚ Maximum 36-400C, Minimum-5-9

0C

⮚ Spores are killed at 620C, but in ice they survive for more than 3 days.

⮚ For spore germination, 100% humidity is essential.

APPLE SCAB

⮚ It is caused by fungus

⮚ Leaf wetness period (in hrs) multiplied by mean temperature (in 0C) should exceed 14

0

when infection is probable(This is applicable for T below 250C and leaf wetness hours

are 9 or more).

DOWNY MILDEW OF GRAPE VINES

Optimum Temperature for germination of sporangia is 10-160C, Tmin is 5

0C.

ALTERNARIA BLIGHT IN CUCURBITS

⮚ Severe during kharif.

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⮚ Spore germination requires RH above 85% and is optimum between 250C & 28

0C.

⮚ A minimum period of 48 hrs of very high RH is required for successful infection.

C. CLIMATIC CLASSIFICATION

KOPPEN’S CLASSIFICATION

Koppen classified the climate into 5major classes (A, B, C, D, and E). 4 of these major

classes (A, C, D, and E) are based on temperature characteristics however B class has been

classified based on precipitation and temperature characteristics. Temperature characteristics

of 5 major classes are as follows-

CLASSES TYPES

A. Tropical Rainy Climate

Average Temperature of the coldest month is more than >180C.

B. Dry climate

Here, Evaporation > Precipitation, low temperature limit.

C. Humid mesothermal climate

Average temperature of the coldest one is between 180C to -3

0C and average temperature

of the warmest month is more than 100C.

D. Humid microthermal climate

Average temperature of the coldest month is <-30C and temperature of warmest month is

>100C.

E. Polar climate

Warmest month temperature is <100C.

Except E Class each of the above primary classes are further subdivided into 2 or more

secondary categories.

KOPPEN’S CLIMATIC CLASSIFICATION OF INDIA

Analyzed according to the Koppen’s system the climate of India resolves into six major

climatic subtypes, their influence give rise to desert in the west, alpine tundra and glaciers

in the north, humid, tropical regions supporting rain forests in the southwest and Indian

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ocean island territories that flank the Indian subcontinent. Regions are different but have

clustered microclimates. The nation is largely subject to four seasons: winter (January

and February), summer (March to May), a monsoon (rainy) season (June to September)

and a post monsoon period (October to December).

India’s geography and geology are climatically pivotal. The Thar Desert in the North

West and the Himalayas in the north work to affect a culturally and economically break

all monsoonal regime. As earth’s highest and most massive mountain range the

Himalayan system bars the influx of katabatic winds from the icy Tibetan plateau and

northerly central India. Most of north India is thus kept warm or is only mildly chilly or

cold during winter the same thermal dam keeps most regions in India hot in summer.

THORNTHWAITE’S METHOD

A.1931 Scheme

He introduced climatic classification based on climatic efficiency. He used two climatic indices-

1. Temperature efficiency (TE)

2. Precipitation efficiency (PE)

The TE is calculated as, TE=1/4∑

Where,Ti= Mean temperature in 0F in ith month.

i=1 to 12 is because of 12 months.

PE= ∑

10/9

Where, Pi= Mean precipitation in ith Month.

TE SYMBOL DESCRIPTION PE SYMBOL DESCRIPTION

>127 A Tropical >127 A Per humid

64-127 B Mesothermal 64.127 B Humid

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32-63 C Microthermal 32-63 C Sub humid

16-31 D Taiga 16-31 D Semiarid

1-15 E Tundra <16 E Arid

<0 F Frost ---- ----- ---

B. 1948 SCHEME

In 1948, he introduced the concept of potential evapotranspiration (PE) and the soil water

balance. He defined potential evapotranspiration as the water loss from large homogeneous

vegetation areas under sufficient water condition and PE is primarily a function of climatic

condition and not a function of type of vegetation, soil type, soil moisture content.

PE is calculated from the mean monthly temperature as follows-

PE=

a

Where,

PE=Potential evapotranspiration (in cm)

I=Sum of 12 months of (t/5)1.514

a=Function of I.

t=Temperature in .

By comparing precipitation and PE, the surplus water (s) available for runoff and deep

percolation and the water deficit (d) can be calculated through the soil water balance

computation. By combining s and d the moisture index (Im) is calculated as,

Im=Ih-0.6Ia=100s-60d/PE

Where, Im= moisture index

Ih= humidity index

Ia= aridity index

The different climate types can be delineated by using moisture index as under-

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SYMBOL CLIMATE TYPES MOISTURE INDEX

A Per humid 100

B4 Humid 80 - 100

B3 Humid 60-80

B2 Humid 40-60

B1 Humid 20-40

C2 Dry sub humid 0-20

C1 Moist sub humid -20-0

D Semi-arid -20- -40

E Arid -40- -60

He subdivided the climate type based on humidity and aridity index-

SYMBOL MOIST CLIMATES (A,B,C2) ARIDITY INDEX (%)

γ(Gamma) Little or no water deficiency 0-10

S1 Moderate summer water deficiency 10-20

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W1 Moderate winter water deficiency 10-20

S2 Large summer water deficiency 20

W2 Large winter water deficiency 20

Symbol Dry Climates (C1,D,E) Humidity index (%)

D Little or no water surplus 0-16.7

S1 Moderate summer water surplus 16.7-33.3

W1 Moderate winter water surplus 16.7-33.3

S2 Large summer water surplus 33.3

W2 Large winter water surplus 33.3

PHYSICAL CLIMATE

Physical climate is simply a solar climate modified by the atmosphere and by the various

controls. We will consider in this chapter the effects of these controllers on the climate.

EFFECT OF VARIOUS CLIMATIC CONTROLS ON CLIMATE-

1. Effect of latitude on the climate (Solar climate)-

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The sun or we may say latitude is the principal control of climate. The climate of any place

by solar radiation is called the solar climate. Solar radiation is named as insolation. The heat

energy received from the sun at any place depends on the following factors-

a. Distance from the sun since insolation varies inversely as square of distance.

b. Inclination of the rays to the solar elevation, since the rays when falling obliquely upon a

surface are spread out over a larger area than when falling normally.

c. Duration –i.e., length of the day.

d. Transmission and absorption by the atmosphere.

e. Output of solar radiation.

2. Mountain and Plateau Climates (Effect of altitude on climate)-

Altitude also influences the climate at a given place as the various controls vary with altitude.

Thus, climate at mountain and plateau are different. The climates on mountains are

characterized by decrease in temperature, pressure and absolute humidity. They are also

characterized by an increase in insolation and in relative humidity. The mountains are cool in

summer because increase in loss of heat by radiation (40%) is more than increase in gain of

heat by insolation (20%).Precipitation increases with increase in altitude. Winds of local

nature such as mountain and valley breeze exist.

3. Marine Climate (effect of water on climate)-

Marine climate exists wherever water is the dominant control. They are therefore found over the

open ocean on small islands and along coasts. Marine climates are characterized by moderate

temperatures with small diurnal and annual ranges by high humidity both absolute and relative

and by much cloudiness and rainfall.

4. Continental Climate (effect of land on climate)-

Continental climate is exactly opposite to the marine climate. The land body has lower specific

heat as compared to the specific heat of water on sea. The temperature ranges, both annual and

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diurnal are large. The limited amount of water for evaporation is responsible for low relative

humidity. The higher temperature of summer and the greater water vapor content (i.e., absolute

humidity) of the air during that season favor more convection than in winter but the average

percentage of cloudiness may vary little with the season since relative humidity is greater in

winter.

5. Desert Climate-

Desert climate is also referred to as extreme continental climate because of the similarity in the

high ranges of temperatures, humidity, cloudiness and rainfall. Two physical characteristics of

the deserts are-

a. A low relative humidity that results in a small amount of clouds but unless there is sufficient

cooling of the air no precipitation takes place.

b. A great diurnal range of temperature.

6. Monsoon Climate-

In winter, continents favor high pressure and outflowing wind and in summer they favor low

pressure and inflowing wind. Oceans favors the opposite conditions, high pressure and out

flowing wind in summer and low pressure and inflowing wind in winter. Thus, in winter the

wind flows from continents to oceans and in summer wind flows in the opposite direction

that is from ocean to continents and these winds are called monsoon winds and climate is

called as monsoon climate. A monsoon climate is characterized by:

1. In summer, high humidity (Both relative and absolute) and intense rainfall.

2. In winter, low humidity, little or no precipitation and clear skies.

Such climates exist in India, southern and eastern Asia, east central Africa and northern

Australia.

AGROCLIMATIC REGIONS OF INDIA

According to the Planning Commission (1989), there are 15 Agroclimatic zones in India.

1. Western Himalayan Regions: [J&K, HP, UP hills (silty loam soil)]

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2. High Rainfall Regions: (7 Sisters state, Darjeeling hills, Jalpaiguri)

Run off problem

3. Lower genetic plains: (Regions in WB)

⮚ Ground water utilization is more than 35%.

⮚ This zone accounts for 12% of the country's rice production.

4. Mid Gangetic Plains: (12 districts of UP East, 27 districts of Bihar)

⮚ 16 million hectares of area.

⮚ Rainfall is high, 61% of the area is under rainfed cultivation.

⮚ Cropping intensity is 142%.

5. Upper Gangetic Plains: (32 Districts)

⮚ Irrigation intensity is 131%.


⮚ Production of wheat and rice is high.

6. Trans Gangetic Plains:(Punjab, Haryana, Delhi, Chandigarh and Sriganganagar in

Rajasthan)

Highest net sown area, highest irrigated area, highest cropping intensity, highest ground

water utilization.

7. Eastern Plateau and Hills:(Odisha Hills, North Odisha, Madhya PradeshEastern Hillsand

Plateau, Chhattisgarh, South and West Bengal Hills)

⮚ Kharif (82% of area under rice)

⮚ Rabi (52% of area under oil seeds)

8. Central Plateau and Hills: (46 Districts of Madhya Pradesh, U.P and Rajasthan)

25% of the area is under rainfed.

9. Western Plateau and Hills: (Parts of Maharashtra, Madhya Pradesh and Rajasthan)

⮚ Average annual rainfall is 904 mm.

⮚ Irrigated area is 12.4%.

⮚ Sorghum and cotton are major crops.

⮚ 50% of the country's sorghum production.

⮚ Best quality of orange, grape, banana.

10. Southern Plateau and Hills: (35 Districts of Andhra Pradesh, Karnataka and Tamil Nadu)

⮚ Semi-arid zone.

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⮚ 81% of the area is under rainfed farming.

⮚ 11% cropping intensity.

11. East Coast Plains and Hills: (Coast of Odisha, North coastal regions of Andhra Pradesh

and South coastal Tamil Nadu)

⮚ 20.3% of India’s rice production and 17% of groundnut.

⮚ Alkaline & saline soils.

12. West Coast Plains and Hills: (West Coast of Tamil Nadu, Kerala, Karnataka,

Maharashtra and Goa)

13. Gujarat Plains and Hills(19 districts of Gujarat)

⮚ 22.5% area is irrigated.

⮚ 78% of rainfed farming.

14. Western Dry Region(9 districts of Rajasthan)

⮚ Desert

⮚ Average rainfall 400 mm.

⮚ 1.2% forest area &4.3% pasture.


15. ISLAND REGION (Andaman and Nicobar, Lakshadweep)

⮚ Half Cropped area under coconut

⮚ 3000 mm rainfall

D. RADIATIONS LAWS

PLANCK'S LAW

Electromagnetic radiation consists of the flow of quanta or particles. The energy content (E) of

each quantum is proportional to the frequency and it is given by the following equation.

E=hν

Where, h=Planck's constant

=6.625 x 10-27

erg sec-1

The equation indicates that the greater the frequency the greater is the energy of the quantum.

KIRCHOFF’S LAW

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Any grey object (other than a perfect black body) that receives radiation disposes of a part of it in

reflection and transmission. The values of absorptivity, reflectivity and transmissivity are less

than or equal to unity.

This law states that the absorptivity ‘a’ of an object for radiation of a specific wavelength

is equal to its emissivity ‘e’ for the same wavelength.

a (λ)=e (λ)

STEFAN –BOLTZMAN LAW

This law states that the intensity of radiation emitted by a radiating body is proportional to the

fourth power of the absolute temperature of that body.

Flux= σT4

Here σ is Stefan Boltzmann’s constant (5.67 x 10-5

erg.cm-2

sec-1

k-4

) and T is the absolute

temperature of the body.

WEIN’S LAW

The wavelength of maximum intensity of emission from a black body is inversely proportional to

the absolute temperature (T) of the body. Thus,

Wave length (λ) of maximum intensity (µm)=2897/T

LAMBERT’S LAW

This law states that the permeability of the atmosphere to solar radiation. The intensity of solar

radiation on a vertical irradiation at the earth’s surface is given by the equation.Im=I0qm.

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REFERENCES

Brunt, D. (1952).Physical and Dynamical Meteorology, Cambridge University Press.pp 1-428.

Byers, H. R. (1974).General Meteorology, McGraw-Hill, New York.pp 1-461.

Lal, D. S. (2014).Climatology, Sharda PustakBhawan, Allahabad.pp 1-448. Mavi, H. S.

(2010).Introduction to Agrometeorology, Oxford & IBH Publishing Co. pp 1-286.

Mote, B. M and Sahu, D. D. (2014).Principles of Agricultural Meteorology, Scientific

Publishers, India.pp 1-197.

Murthy, V. R. K. (1996). Basic Principles of Agricultural Meteorology, Shri Venkateswar

Publishers, Hyderabad.pp 1-261.

Purohit, S. S. and Ranjan, R. (2003).Ecology, Environment and Pollution, Agrobios, Jodhpur,

India.pp 223-308.

Siddhartha, K. (2013). Atmosphere, Weather & Climate, Kisalaya Publications Pvt. Limited,

New Delhi, India. pp 1-547.

Varshneya, M.C. and Pillai, P. Balakrishna. (2018). Textbook of Agricultural Meteorology,

Indian Council of Agricultural Research, New Delhi, India. pp 1-221.

Documents

Question Bank on Agricultural Meteorology