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Monsoon origin theories, Earths atmosphere evolution, climate change, factors of climatic change, climatic variability, how these influencing Indian monsoon rainfall, EL Nino, La Nino, ENSO, Indian ocean dipole, MJO etc
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Effect of climatic variability on Indian summer monsoon rainfall
Department of AgronomyAgricultural College, Bapatla
Credit seminar on
By Medida Sunil Kumar BAD-14-06
1
Contents of presentation
Introduction on monsoon & Indian summer monsoon
Climatic variability & factors affecting variability
Effect of climatic variability on Indian summer monsoon
Future projections of Indian summer monsoon variability
Conclusion
2
Introduction Word “monsoon” is derived from the Arabic word for season.
Monsoon is defined as seasonally reversing wind system
accompanied by seasonal changes in atmospheric circulation
and precipitation.
Indian summer monsoon is a branch of Asiatic monsoon.
Primary theories behind the cause of monsoon is the
differential heating of ocean and land (Halley, 1686) and
shifts in inter tropical conversion zone.
3
Fig-1:Thermal concept of the origin of monsoon by Halley (1686)
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Fig-3: Global surface & upper air circulation
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Fig-2: Surface global circulations of air
Fig-4: Origin of monsoon by modified Flohn’s (1951) concept
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Fig-5: Propagation of south east trade winds as south west trade winds after crossing equator
7
Climate of Earth
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1. Earliest Atmosphere:
Primarily H2, water vapor, CH4 and NH4 like Jupiter and Saturn.
2. Second Atmosphere:
Consisting largely of N2, CO2 and inert gases, was produced by volcanism
Initial period Sun’s out put was 30% lower solar radiance associated one cold glacial
phase about 2.4 billion years ago
Late Archaean eon O2 containing atmosphere began to develop, apparently produced
by photosynthesizing cyanobacteria
3. Third Atmosphere:
Movement of plate tectonics and volcanism released CO2
Free oxygen did not exist in the atmosphere until about 2.4 billion years ago
The amount of oxygen in the atmosphere has fluctuated over the last 600 million years,
significantly higher than today's 21%.
Natural green house effect
Evolution of earth’s atmosphere
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Causes & consequences of climate change
Natural Causes
Volcanoes
Solar Output
Earth's Orbit around the Sun
Human Induced Causes Fossil Fuels
Industrial Revolution
Change in Land use
Increase in green house gases
Global warming
Climate variabulity & change 10
Effect of climatic variability on Indian summer monsoon
Inter-annual monsoon variability
Intra-seasonal monsoon variability
Decadal monsoon variability
Active and break spells
Cyclonic disturbances
El Nino southern oscillation (ENSO)
11
I. Inter-annual varIabIlIty
12
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.
Fig-6: Inter-annual variability of all India June rainfallPattanaik, 2012
13
Excess+20= 21yExcess+40=3y
Deficit -20=22yDeficit-40=4y
Normal=164.7 mm (18.5%)
Fig-7: Change in Indian summer monsoon rainfall of June month in mm during 100 year for 36 meteorological sub-divisions
Guhathakurta & Rajeevan, 2007
IMD, Pune14
Fig-8: Inter-annual variability of all India July rainfall
Pattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.15
Excess+20 = 6 y Deficit -20 = 11 yDeficit-40 = 3y
Normal = 293.7 mm (33 %)
Fig-9: Change in Indian summer monsoon rainfall of July month in mm during 100 year for 36 meteorological sub-divisions
IMD, Pune
Guhathakurta & Rajeevan, 2007
16
Fig-10: Inter-annual variability of All India August rainfall
Pattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.17
Excess+20 = 13 y Deficit -20 = 10 y
Normal = 262.5 mm (29.5 %)
Fig-11: Change in Indian summer monsoon rainfall of August month in mm during 100 year for 36 meteorological sub-divisions
Guhathakurta & Rajeevan, 2007
IMD, Pune18
Fig-12: Inter-annual variability of All India September rainfallPattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.19
Excess+30 = 11 y Deficit -30 = 12 y
Normal = 169.1 mm (19 %)
Fig-13: Change in Indian summer monsoon rainfall of September month in mm during 100 year for 36 meteorological sub-divisions
Guhathakurta & Rajeevan, 2007
IMD, Pune20
Fig-14:Inter-annual variability of all India summer monsoon rainfall (AISMR) during the period from 1875 to 2010
Pattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.21
Flood years= Mean rainfall 1041mmFlood years= 19
Drought years= Mean rainfall 739 mmDrought years= 24
Fig-15: Change in Indian summer monsoon rainfall in mm during 100 year for 36 meteorological subdivisions. Guhathakurta and Rajeevan, 2007
IMD, Pune22
Fig-16: Mean coefficient of variability (%) of all India summer monsoon rainfall in cm from 1951-2003
Pattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.23
Fig-17: Average frequency (intensity) of occurrence of rainfall events during summer monsoon season (951 to 2005) along with the linear trend line
24
Pattanaik and Rajeevan, 2010
Meteorological applications. 17: 88–104
Table-1: Mean percentage of rainfall amount under different categories of rainfall events (1951-2005)
25Meteorological Applications. 17: 88–104
Pattanaik and Rajeevan, 2010
Fig-18:Inter-annual variability of Indian summer monsoon rainfall (mm) in different district of erstwhile Andhra Pradesh (1971-2009)
El Niño Effect on Climatic Variability and Crop Production: A Case Study for Andhra Pradesh; Res. Bull. No. 2/2011, CRIDA
Rao et al., 2011
26
27
Fig-19: Climatologically daily rainfall anomalies averaged over the all India, central and peninsular India during summer monsoon rainfall period (1966–2010).
J. Earth System Science,123 (5),1129–1145
Prasanna, 2014
II. Intra-annual varIabIlIty
28
Fig-20: Daily mean (mm) and daily coefficient of variability (%) of all India monsoon rainfall (1951-2000). Pattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.29
III. DecaDal varIabIlIty
30
Fig-22:-Decadal composite anomalies of AISMR based on IMD observed rainfall during last 11 decades from 1901-2010. Pattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.
Fig-23: Decadal composite anomalies of AISMR based on IMD observed rainfall during last 11 decades from 1901-2010
Pattanaik, 2012
Chapter-2, Indian Monsoon variability, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 35-77, IMD.
IV. Active & break spells
Periods in which the normalized anomaly of the rainfall over
the monsoon zone exceeds 1 or is less than -1.0 respectively,
provided the criterion is satisfied for at least three consecutive
days.
Break spell of more than 10 days in monsoon period is due to
synoptic convective systems and Madden Julian oscillation.
33
Fig-24: Average percentage of frequency of no rain days during June to September from 1951 to 2005
34
Pattanaik and Rajeevan, 2010
Meteorological Applications. 17: 88–104
Table-2:Frequency distribution of the duration of break spells in per cent (1951–2007)
DurationRajeenvan et al
1950-2007
3-4 405-6 287-8 199-10 311-12 413-14 3>15 3
Rajeevan et al., 2010
35J. Earth System Science.119 (3), 229–247
Table-3:Decadal variabulity of active & break spells (1951-2007)
Period No of Break spell No of Active spell
1951-1960 6 151961-1970 12 201971-1980 12 201981-1990 13 171991-2000 15 172001-2007 12 12
Rajeevan et al., 2010
J. Earth System Science.119 (3), 229–24736
Fig-25: Mean rainfall anomaly during the break spells(1951-2004)Rajeevan et al., 2010
37J. Earth System Science.119 (3), 229–247
Fig-26:Composite of rainfall anomaly (mm/day)for active & break spells (1951-2004) Rajeevan et al., 2010
Active SpellBreak spell
38J. Earth System Science.119 (3), 229–247
Fig-27: Madden Julian Oscillation spatial structure and evolution: a schematic illustrating the large-scale nature and eastward shifting over time. The cloud (sun) icons represent the enhanced (suppressed) phase and the blue arrows indicate the eastward movement.
Courtesy of NOAA Climate Prediction Center39
Fig-28: Composite rainfall anomaly (mm) in respect of 8 strong phases and the weak category of MJO derived using data for the period 1974-2008
Pai et al., 2009
National Climate Centre, Research Report No: 4/200940
41
Fig-29: Effect of Indian ocean dipole summer monsoon rainfall
V. Cyclonic Disturbances
42
Fig-30:The frequency of monsoon depressions in each monsoon season of 1891 to 2007 Joseph, 2012
Chapter-1, Synoptic systems during monsoon season, Monsoon monograph, Tyagi et al (Edt.),vol-2, 1-34 43
Global teleconnections of Indian monsoon
44
S. No Parameter Period of data
Correlation coefficient withAISMR (1971-2000)
1 Arabian sea surface temperature January + February 0.55
2 Eurasian snow cover December -0.46
3 North West Europe temperature January 0.45
4Nino-3 SST anomaly (Previous year)
July to September 0.42
5 South Indian ocean SST index March 0.476 East Asian pressure February + March 0.61
7 50hPa Wind pattern January + February -0.508 Europe pressure gradient January 0.42
9South Indian Ocean zonal wind at 850 hPa
June -0.45
10 Nino 3.4 SST tendency AMJ-JFM -0.46
Table-4: Details of parameters used in new long range forecasting
April-16 45
S. No Predictor Used for forecast
Correlation coefficient with
AISMR(1971-2000)
1NW Europe land surface air temperature April -0.51
2 Equatorial pacific warm water volume April 0.43
3 North Atlantic sea surface temperature April & June 0.36
4Equatorial SE Indian ocean sea surface temperature April & June 0.59
5 East Asia mean sea level pressure April & June -0.31
6Central Pacific Sea surface temperature tendency (Mar+Apr+May) – (Dec+Jan+Feb)
June -0.49
7 North Atlantic mean sea level pressure June -0.46
8North Central Pacific wind at 1.5 km above sea level June -0.44
Table-5:Details of eight parameters used in new forecasting model
46
VI. El Niño southern oscillation
• Defined as oscillation / fluctuations in air pressure
between the tropical eastern and the western Pacific
Ocean waters.
• Oceanic component called El Niño or La Niña and the
atmospheric component is Southern Oscillation.
47
Fig-31: Normal conditions over Pacific ocean
48
TSW=+0.5oCThermocline= 3-6oC
Fig-32: Events of El Niño and La Niño
49
Fig-33: El Niño and La Niño events
50
Fig-34: Oceanic Nino regions
Courtesy by www.intechopen.com
Fig-34:
Table-6:El Niño /La Niño association with all-India summer monsoon rainfall anomalies during 1880-2008.
Parameter
Indian Summer Monsoon RainfallDeficit < - 1.0
Below Normal
- 0.5 to 0.5
Near Normal-0.5 to 0.5
Above Normal
0.5 to 1.0
Excess> 1.0
Total
El Nino(Nino -3> 1.0) 7 5 5 0 1 18
Normal 14 13 39 14 6 86La Nino(Nino -3<-1.0)
0 0 7 7 10 24
Total 21 18 51 21 17 128
Gadgil and Francis, 2012
Chapter-4, Oceans and Indian monsoon, Monsoon monograph, Tyagi et al., (edit) Vol-2, Chapter-2, Pp 129-188, IMD.52
Fig-35: All-India summer monsoon rainfall (1871-2001)(Based on IITM homogeneous monthly rainfall data set)
Flood years: Mean 1041mm Drought years: Mean 739 mm
Courtesy by http://www.tropmet.res.in/~icrp/icrpv11/icrp6.html
VII. Rainfall extremes
54
Fig-36:Average percentage of frequency of rainfall more than 124.4 mm/day during the monsoon season from 1951 to 2005.
55
June July
August September
Pattanaik and Rajeevan, 2010
Meteorological Applications. 17: 88–104
Fig-37: Number of heavy rainfall events from 1950 to 2010
56
Future projections
57
Emissions Scenarios of IPCC• A1:- World of very rapid economic growth, low population growth, and the rapid
introduction of new and more efficient technologies with a substantial reduction in regional differences in per capita income. The A1 scenario family develops into four groups based technological change in the energy system.
• A2:- Heterogeneous world. The underlying theme is self-reliance and preservation of local identities and high population growth with regional Economic development
• B1:- Storyline and scenario family describes a convergent world with the same low population growth as in the A1 storyline, but emphasis is on global solutions to economic, social, and environmental sustainability, including improved equity, but without additional climate initiatives.
• B2:- World in which the emphasis is on local solutions to economic, social, and environmental sustainability with moderate population growth, intermediate levels of economic development, and less rapid and more diverse technological change than in the B1 and A1 storylines. While the scenario is also oriented toward environmental protection and social equity, it focuses on local and regional levels.
58
Fig-38:Projections of future climate of India under four Special Report on emission scenarios of IPCC emission scenario
Murari Lal et al., 2001
Current Science, 81 (9&10), 1196-1207
A1= Rapid economic growth GlobalisationB1=Regionally oriented economic developmentA2=Global environmental sustainability RegionalisationB2= Local environmental sustainability 59
Fig-39: Projected future changes in mean monsoon precipitation (%) with respect to baseline period of 1961–1990.
Krishna Kumar et al., 2012
Current Science, 101(3), 312-32660
Fig-40: Projected future changes in the number of rainy days with respect to the baseline (1961–1990).
Krishna Kumar et al., 2012
Current Science, 101 (3), 312-32661
Fig-41:Projected changes in the intensity of rainfall on a rainy day (mm/day) with respect to the baseline (1961–1990)
Current Science, 101 (3), 312-326
Krishna Kumar et al., 2012
62
Conclusions• Climate of the earth changing form its origin.
• Human induced forces accelerated much more than natural forces resulting global warming over a shorter period on earth’s time scale.
• Annual variabulity was influenced by global teleconnections of Indian summer monsoon.
• Intra-annual variabulity was observed highest in the months of June & September.
• Trend in significant increase in intensity of rainfall was observed with regional variations.
• Projections of future mean summer monsoon precipitation will be increased along with rainfall intensity
63
thank you
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