G. S. Bhat, L. Prashanth Rao and Vinayak Bhat Indian ... OF ATMOSPHERIC THERMAL STRUCTURE DURING...
Transcript of G. S. Bhat, L. Prashanth Rao and Vinayak Bhat Indian ... OF ATMOSPHERIC THERMAL STRUCTURE DURING...
EVOLUTION OF ATMOSPHERIC
THERMAL STRUCTURE
DURING 2003 MONSOON ONSET
G. S. Bhat, L. Prashanth Rao and Vinayak BhatIndian Institute of Science, Bangalore
National Workshop onArabian Sea Monsoon Experiment
(ARMEX)Data Analysis & Modelling
19-21 April, 2006
Acknowledgements: DST, DOD (NCAOR), IMD, Fellow Scientists & Ship Crew,
1. Vertical thermal structure of the Atmosphere
2. Inter-comparison of Vaisala & NCEP data
3. Average characteristics of T, RH & q profiles
over the Indian Ocean
70 72 74 76 78 80 82longitude (E)
10
13
16
19
latit
ude
(N)
Kochi
Goa
20 25 30 35 40 45 500
10
20
30
40
rain
(m
m/d
ay)
04 09 14 19May June
20 25 30 35 40 45 50
1002
1004
1006
1008
1010
1012
pres
sure
(h
Pa)
04 09 14 19
Daily average pressure and rainfall during May-June (SK193)
Holt & Raman, MONEX-79, BLM, 1987)
Temp.Anmly
20 25 30 35 40 45 500
10203040
rain
04 09 14 19May June
NCEP Under estimates the inversion strength
RHAnmly
20 25 30 35 40 45 500
10203040
rain
04 09 14 19May June
Humidity rapidly built up in 8 daysABL - less moist in NCEP
Wind Speed
Wind Direction
15 20 25 30 35 40 45 500
60
120
180
240
300
360
deg
04 09 14 19May June
wind direction
15 20 25 30 35 40 45 500
5
10
15
m/s
04 09 14 19
wind speed
SK193:
0 10 20 30 40
wind speed (m/s)
1000
900
800
700
600
500
400
300
200
100
0
pres
sure
(m
b)
6/6, 11306/6, 14306/6, 17307/6, 05307/6, 11307/6, 1730
Upper Winds
-80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30
temperature (deg. C)
1000
900
800
700
600
500
400
300
200
100
0
pres
sure
(m
b)
6/6, 11306/6, 14306/6, 17307/6, 05307/6, 11307/6, 1730
-80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30
temperature (deg. C)
1000
900
800
700
600
500
400
300
200
100
0
pres
sure
(m
b)
20032002
Some Remarks:
1. Strong diurnal variation in clouding & rainfall( at least 8 Satellite Images /day)
2. Cloud shape over the AS during 2003 monsoon- long cloud bands, not seen in 2002.
3. Over AS - what dictates convection?
4. AWSs working fine at all 4 stations, however, had serious problems at Vengurla:
- set alright- added soil temperature & solar radiation
Fate of these AWS?
Need for a datalogger that can store 12 months data
2 AWSs given to IAF - letter from DSTminutes of PAMC
Clouds : Rolls?
BOBMEX - Jul-Agu 99
ARMEX:1 : Jun-Aug 20022 : Mar-Jun 2003
IRSP4: Mar 2001
SOC : Jan-Feb 2004
longitude (E)
latit
ude
65 70 75 80 85 90-5
0
5
10
15
20
25
BoB
ArabianSea
INDIA
Goa
MUM
Radiosonde positions
Observations1. Mean2. Standard Deviation
Models/Indirect1. Sounders on Satellites2. Numerical Models
Deg. C
heig
ht(
km)
-90 -60 -30 0 300
5
10
15
20
ARMEX2aARMEX2bIRSP4SOCBOBMEXARMEX1
Temperature
Average (Tropical) Soundings in the Indian Ocean
Deg. C
heig
ht(
km)
0 1 2 3 4 50
5
10
15
20
ARMEX2aARMEX2bIRSP4SOCBOBMEXARMEX1
Temperature Variance
longitude (E)
lati
tud
e
65 70 75 80 85 90-5
0
5
10
15
20
25
BoB
ArabianSea
INDIA
Goa
MUM
Lowest 15 km : T variance <2oC
%
heig
ht(
km)
0 20 40 60 80 1000
5
10
15
20
ARMEX2aARMEX2bIRSP4SOCBOBMEXARMEX1
Relative humidity
longitude (E)
latit
ude
65 70 75 80 85 90-5
0
5
10
15
20
25
BoB
ArabianSea
INDIA
Goa
MUM
%
heig
ht(
km)
0 20 400
5
10
15
20
ARMEX2aARMEX2bIRSP4SOCBOBMEXARMEX1
Relative humidity Variance
longitude (E)
lati
tud
e
65 70 75 80 85 90-5
0
5
10
15
20
25
BoB
ArabianSea
INDIA
Goa
MUM
RH variance maximum in mid-troposphere
g/kg
heig
ht(
km)
0 5 10 15 200
5
10
15
ARMEX2aARMEX2bIRSP4SOCBOBMEXARMEX1
Average mixing Ratio
longitude (E)
lati
tud
e
65 70 75 80 85 90-5
0
5
10
15
20
25
BoB
ArabianSea
INDIA
Goa
MUM
g/kg
heig
ht(
km)
0 1 2 3 4 50
5
10
15
ARMEX2aARMEX2bIRSP4SOCBOBMEXARMEX1
Mixing Ratio Variance
longitude (E)
lati
tud
e
65 70 75 80 85 90-5
0
5
10
15
20
25
BoB
ArabianSea
INDIA
Goa
MUM
Maximum mixing ratio variance: ~1-2 km (inversion3-4 km
Integrated Water Vapour
NIO: MONSOON
Spring
days
kg/m
**2
0 10 20 30 40 50 6010
20
30
40
50
60
70
bbxarmex1sk193irsp4socsk190 spring