AMF1 MEASUREMENTS AT

NAINITAL AND RELATED

RESEARCH AT ARIES

Manish Naja

ASR Fall Working Group meeting[12-16 Sep 2011]

Aryabhatta Research Institute of Observational Sciences, Nainital

AMF1 deployment is under GVAX program, funded by ARM, DOEPI – Rao Kotamarthi, CO-PIs – SK Satheesh, R. Sagar

DirectorRam Sagar

ScientistsP. P.ant, M. Naja, N. Singh, Phani Kumar, U. C. Dumka, Vimlesh Kumar

EngineersS. Bhattacharjee, C. Prakash, Ashish Kumar

PDFS. Sahai

Ph D studentsRajesh Kumar, N. Ojha, T. Sarangi, H. Joshi, K. Shukla, P. Bhardwaj, R Solanki

~200 km2000 m

4000 m

Observation Sites:

Devasthal – 29.4N, 79.7E, ~ 2450 m

Nainital – 29.4N, 79.5E, ~ 1958 m

Pantnagar – 29.0N , 79.5E, ~ 231 m

Dehradun – 30.3N, 78E, ~700 m

China

India

Nepal

China

Nepal

India

Himalayan range4 - 8 km

IGP – 1000-more persons/km2

Nainital – 25-100 persons/km2

Population density

Motivation

Central Himalayas

•Better Regional Representative

•Long-range Transport

� Anthropogenic emissions are increasing

� IGP – Highest Polluted Region

� Higher solar radiation leads to higher water

vapor content and intense photochemistry

AOD TTO Ozone

To Nainital City

ARIES 29.36N, 79.45 E, 1958 m

� Aerosols (Since January 2002)

� Trace Gases (Since September 2006)

� Lidar

� ST Radar (upcoming)

Atmospheric Science Group

– AOD (MWR, Microtops & AERONET)

– Black Carbon– Aerosols number concentrations

– Particulate Matter

– Pollutants (Ozone, CO, NO, NOy, CH4 NMHCs , SO2)

– Greenhouse gases (CO2, N2O and SF6)

– Aerosols

Important Results

Lower value of AOD, particularly in winter. (JGR)

Aerosols RF is much lower at Nainital (JGR)

Air back-trajectories during dust episode period

50 60 70 80 90 100

Latitude (deg)

10

20

30

A r a b i a n S e a

*

[a]

Thar Desert Nainital

INDIA

PAKISTAN

Long-range transport from Thar Desert (GRL)Comparison

with MISR

Black Carbon at Nainital & Pantnagar

Pantnagar

Nainital

BC levels at Pantnagar– higher by 5-6 times

Diurnal changes at Nainital-Pantnagar

Ozone levels show clear

daytime peak at Pantnagar

and Dehradun in contrast

with Nainital

Nighttime ozone levels are lower at Pantnagar

(…… Ozone titration chemistry is stronger)

Diurnal Variations at Nainital, Pantnagar and Dehradun

Surface ozone at Pantnagar and NainitalOzone at Pantnagar (ppbv)

Ozone at Nainital

Daytime: the atmospheres of NTL and

PNT gets coupled due to boundary

layer evolution.

Surface Ozone Seasonality at Nainital

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec0

5

10

15

20Stratospheric Ozone

European Emissions

South Asia Emissions

[b]Average Ozone (ppbv)

20

30

40

50

60

70

80

Average Ozone (Observations)

Nainital_2000m (Model)

Nainital_surface (Model)

[a]

� Differences in model and observations may be due to coarser resolution, emissions

uncertainties and errors in meteorology of global model.

� Model and trajectory based estimates of contributions from downward transport is

about 4-6 ppbv

[JGR 2010]

Ozone and Air Flows

0 1 2 3 4 5 6 7 8 9 10

Days over Northern Indian Subcontinent

0 1 2 3 4 5 6 7 8 9 10

Average Ozone (ppbv)

20

40

60

80

20

40

60

80Winter Spring

Summer/Monsoon Autumn

Rate : 0.3 ppbv/day Rate: 3.27 ppbv/day

Rate: -1.1 ppbv/day Rate: 0.45 ppbv/day

Season Reg. BG O3 (ppbv)

Winter 41.4 ± 2.9

Spring 48.3 ± 5.0

Summer 34.7 ± 2.8

Autumn 39.2 ± 2.9

Month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Average Ozone (ppbv)

0

20

40

60

80

Average Ozone (all data)

Ozone in Regionally Polluted air masses

Ozone in Afric a/Europe air masses

Ozone in Marine air masse s

Air-Mass O3 (ppbv)

Regionally Polluted 47.1 ± 16.7

Marine 29.7 ± 11.7

Africa/Europe 57.7 ± 15.4

Pantnagar daytime

Nainital

�Ozone seasonality is characterized by springtime maxima (55-60 ppbv) and summer/

monsoon minima (10-15 ppbv).

�Mixing depth at Pantnagar (from HYSPLIT) also shows maxima (3 to 5 km) during spring.

�Interestingly, daytime ozone levels at Pantnagar show similar variations as at Nainital (Role

of Mixing)

Seasonal variations in surface ozone at Pantnagar

Chemical Box model simulations (NCAR Master Mechanism)

� To simulate the chemical evolution of an air parcel, neglecting

any coupling between chemistry and dynamics, however, it

includes boundary layer evolution.

� Basic inputs to the model are site parameters, boundary layer,

meteorological conditions (Temperature, clouds), species of

interest, emissions, initial & background concentrations.

� Ozone diurnal variations, simulated for Nainital (Clean) and

Pantnagar (urban) shows reasonable agreement with the observations.

Clean

Urban

NOx(ppbv)

Total NMHCs (ppbv)

�Ozone production is more sensitive to NOX at

Pantnagar.

�Possible future increase in emissions from this region

would result in rapid increase in ozone.

0

200

400

600

800 2007

Fire Counts

0

200

400

600

800

Month

Mar Apr May0

200

400

600

800

2009

2008

Biomass BurningBiomass Burning

Max fire activity

(15 April – 30 May)

M o n th

J an F eb M ar A p r M a y J u n J ul A u g Se p O c t N o v D ec

Fire Counts

0

1 0 0

2 0 0

3 0 0

4 0 0

5 0 0

6 0 0

7 0 0

8 0 0

M O D IS (2 0 0 8 )

Fire over the Northern India

Enhancement in BC and Ozone

Enhancement in Radiative forcing

[JGR 2011]

Temperature

Vertical distribution

of Temperature,

Relative Humidity

and Ozone at

ARIES, Nainital.

Occasionally very high

wind speed (50 m/s) are

observed in middle and

upper troposphere. (may

be associated with tropical

Jets)

Wind Speed

�Elevated ozone is noticed in the middle and upper troposphere.

�Signatures of Stratospheric intrusions are seen in preliminary analysis.

Ozone

WRF-Chem Model

Input Data

Grid Spacing : 45 Km; Model Top Pressure: 10 hPa; Center lon (lat): 80o E(25o N)

Grid Points (x,y,z): (90,90,51); Simulation Time Step: 4*grid spacing = 180 secs

�� Geographical Data Geographical Data –– USGSUSGS

�� Meteorological Data Meteorological Data –– FNLFNL

�� Anthropogenic Emissions Anthropogenic Emissions ––

RETRO/ Zhang et al. (2009) RETRO/ Zhang et al. (2009)

�� Biogenic Emissions Biogenic Emissions --

MEGAN MEGAN

�� FireFire--Emissions Emissions –– Wiedinmyer Wiedinmyer

et al. (2006)et al. (2006)

�� Initial and lateral boundary Initial and lateral boundary

conditions for chemical conditions for chemical species species ––MOZART 4MOZART 4

Thanks to NCAR, Boulder group (G Pfister, M Barth and G P Brasseur)

WRF-Chem: comparison with RAOB

Radiosonde data from 34

stations within India are used

for evaluating temperature and

dew point temperature

WRF-Chem

Vs

AIRS

WRF-Chem Vs TES Ozone

(Cont…)

1 – North India, 2 – West India, 3 – East India, 4 – South India, 5 - Burma

WRF-Chem Vs. MODIS Terra AOD (550 nm)WRF-Chem (45 km)

MODIS (1 deg.)

Greenhouse gases

� Weekly Air samples (1400 Hours IST) are

collected at a cold trap (-300C)

� Analysis is done using NDIR analyzer and

GC at NIES, Japan

De-SeasonalizedLong term trend

CO2�1.65 -2.38 ppmv/yr, N2O� 0.75 ppbv/yr, SF6� 0.24 pptv/yr

Global growth rates:

Stratosphere Troposphere (ST) Radar (upcoming)

Highlights:� Studies on winds, monsoon dynamics and Troposphere Stratosphere exchange

� Frequency : 206.5 MHz

� Area Covered : 30x30 m

� Continuous and high resolution winds� ~10 min for full profile� 50 to 300 m� Velocity resolution : 0.1 m/s to 2 m/s

T/R module floor

(Ceiling for GF)

Arrangement to put

T/R modules

Ground Floor

(control room & work place)

Antenna floor

(Roof top)

Nainital

Kanpur

Agra

Shillong

Kolkata

Nagpur Bhubneshwar

Vishakhapatnam

Hyderabad

Gadanki

Thumba

Ahmedabad

Mt. Abu

Port Blair

ThalasseryOoty

Anantpur

Kullu

High altitude background sites under ISRO network

Mt. Abu

Nainital

Ooty

•Model Validation

•Background levels

•Regional Pollutions

•Long Range Transport

RAWEX-GVAXRegional Aerosols Warming Experiment

Ganges Valley Aerosols ExperimentA multi institutional project

DOE (USA), ISRO, IISc and ARIES

A major international initiative after about 13 years

AMF1 set up

atARIES

Nainital

Doppler Lidar

0 20000 40000 60000 80000 100000

-1000

0

1000

2000

3000

4000

5000

6000

7000

8000

Cloud Height (m)

Time(s)

Cloud base1

Cloud base 2

Ceilometer

Tropopause Characteristics over Nainital

�Tropopause characteristics show

significant variability over this region.

�Reasonably good agreement is seen

between radiosonde and satellite

observations.

�Generally Tropopause is located

between 14 to 18 km while on few

occasion it is observed at lower

altitudes (possibility of multiple

tropopause).

Tropopause estimation has been

made usingWMO criteria. .

Future Change ……..

……… it ……… it is in the tropicsis in the tropics