lba/physical climate moist convection in the amazon
TRANSCRIPT
LBA/Physical Climate
Moist Convection in the Amazon
Things models should do that LBA data has pointed out
• easterlies/westerlies and convection
• land features effects on convection– forest vs non-forest– topography– river vs land
Rondônia 1999 850 hPa zonal wind - CPTEC
Santarém 1999 850 hPa zonal wind - CPTEC
Manaus 1999 850 hPa zonal wind - CPTEC
Summers of 1980 to 1999
Carvalho et al , 2002
Summers of 1980 to 1999
Carvalho et al , 2002
Blakeslee, 2000
Petersen, 2000
Blakeslee,2000
Rickenbach et al. 2000
Tokai, 2000
Anagnostou & Morales, 2002
Hourly rainfall rate
from TOGA radar
Hourly average
cloud fraction
GOES
TOGA
6:20 7:20 8:20 9:20 10:20 11:20 12:20
Local Time
Time of first radar echoes
S-Pol Jan/Feb 1999
easterlies
westerlies
0,0
20,0
40,0
60,0
80,0
100,0
Forest Forest
Interface
Pasture
Interface
Pasture
Vegetation at Location of Convection InitiationWet Season - All Cases
TOGA
SPOL
0,0
20,0
40,0
60,0
80,0
100,0
< 95 100 - 295 300 - 495 500 - 695 > 700
Altitude (m)
Altitude at Location of Convection Initiation
Wet Season - All Cases
TOGA
SPOL0,0
20,0
40,060,0
80,0Fr
eque
ncy
(%)
Forest -
Below
Average
Forest -
Above
Average
Pasture -
Below
Average
Pasture -
Above
Average
Vegetation Altitude at Location of Convection Initiation
Wet Season - All Cases
TOGA
SPOL
Pereira et al 2000
TRMM-LBA Region: Forest vs. Non-Forest
SPOL
Profiler
TOGAFOREST
NON-FOREST
Carey et al 2001
TRMM-LBA Region: Topography
“Elevated”>= 223 m
“Non-Elevated”< 223 m
Carey et al 2001
0.001
0.01
0.1
1
10
100
0 10 20 30 40 50 60 70 80 90 100 110 120
Rain Rate Bin (mm h -1)
Fre
qu
en
cy
(%
)
Forested
Non Forested
Category Unconditional Rain Rate mm h-1)
Conditional Rain Rate (mm h-1)
Forested 0.2612 1.834
Non-Forested 0.2436 1.517
Relative Difference
(F-NF)/[(F+NF)/2]
+ 7 % + 19 %
Effects of Deforestation on Rain Rate Statistics
Carey et al 2001
Category Ru (mm h-1) Rc (mm h-1) Fractional Grid Coverage (%)
ALL 0.2535 1.716 100
NE 0.2461 1.507 48.7
E 0.2664 2.004 2 51.3
NF 0.2436 1.517 29.2
F 0.2612 1.834 3
70.8
NF NE 0.2402 1.400 17.6
NF E 0.2504 1.739 4 11.6
F NE 0.2519 1.588 31.1
F E 0.2721 2.097 1
39.7
Ru = Unconditional Mean Rain RateRc = Conditional Mean Rain RateNE = Non Elevated (< 223 m)
E = Elevated ( 223 m)F = ForestedNF = Non Forested
Fractional Rain Duration = % of grid boxes for land type category with rain (R > 0)
Fractional Grid Coverage = % of all grid boxes for land type category
KEY:
TRMM-LBA: Effect of land type on rainfall statistics
Carey et al 2001
Carey et al 2001
Category February 1999 Mean Rain Depth (mm)
Forested 198.5
Non-Forested 183.1
Relative Difference
(F-NF)/[(F+NF)/2]
8 %
TRMM-LBA: SPOL Derived Rain Depth (mm)February 1999
0
1
2
3
4
5
6
7
8
9
10
5 25 45 65 85 105
125
145
165
185
205
225
245
265
285
305
325
345
365
385
mor
e
Rain Depth Bin (mm)
Fra
cti
on
of
Gri
d C
ells
(%
) Forested
Non-Forested
Effects of Deforestation on Cumulative Rain Depth
Carey et al 2001
Category February 1999 Mean Rain Depth (mm)
ALL 194.0
NE 181.0
E 206.4
NF 183.1
F 198.5
NF NE 176.2
NF E 193.6
F NE 183.7
F E 210.7
Land Effects on Rain Depth
Carey et al 2001
TRMM-LBA: S-POL Derived Rain Depth (mm)February 1999
0
1
2
3
4
5
6
7
8
9
10
Rain Depth Bin (mm)
Fra
cti
on
of
Gri
d C
ell
s (
%)
Elevated
Non-Elevated
Effects of Elevation on Rain Depth
Carey et al 2001
0
2
4
6
8
10
12
5 25
45
65
85
10
5
12
5
14
5
16
5
18
5
20
5
22
5
24
5
26
5
28
5
30
5
32
5
34
5
36
5
38
5
mo
re
Rain Depth Bin (mm)F
rac
tio
n o
f G
rid
Ce
lls
(%
)
F E
NF E
0
2
4
6
8
10
12
5
25
45
65
85
10
5
12
5
14
5
16
5
18
5
20
5
22
5
24
5
26
5
28
5
30
5
32
5
34
5
36
5
38
5
mo
re
Rain Depth Bin (mm)
Fra
ctio
n o
f G
rid
Cel
ls (
%)
F NE
NF NE
Elevated Only
Non-Elevated Only
ForestedNon-Forested
ForestedNon-Forested
Carey et al 2001
29,0
29,5
30,0
30,5
31,0
31,5
32,0
08:00 11:00 14:00 17:00
Local time (hours)
Wa
ter
tem
pe
ratu
re (
de
g.C
)
0.1m
0.3 m
0.7 m
1.0 m
c
23 July 2001 Tapajós
(from Pindobal to Boim and back)
26
27
28
29
30
31
32
10:00 10:30 11:00 11:30 12:00
Local time (hours)W
ate
r te
mp
era
ture
(d
eg
.C)
0.1m
0.3 m
0.7 m
1.0 m
28 July 2001 Tapajós & Amazonas
(red line: temperature where the two rivers merge)
-4,0
-2,0
0,0
2,0
4,0
0 6 12 18 24
UTC (for Local time subtract 4 hrs)
U (
m/s
)
24 u
26 u
27 u
28 u
29 u
30 u
31 u
1 u
-4,0
-2,0
0,0
2,0
4,0
0 4 8 12 16 20 24
UTC
v (
m/s
)
24 v
26 v
27 v
28 v
29 v
30 v
31 v
1 v
AWS Jamaraquá
24 July / 1 August 2001
West
East
South
North
Winds at Belterra
radiosonde
Pressure (mb)
Winds and potential temperature
Belterra radiosonde
Wind vector 23 M ABOVE THE SURFACE
wind – streamlines perpendicular to the Tapajós river
Potencial temperature
Model improvements based on LBA data
• USP - RAMS reanalysis - changes in cumulus parameterization
CPTECTHERMODYNAMIM STRUCTURE OF CONVECTIVE ACTIVITY AT WET-AMC/LBA
SITES AND ETA MODEL VALIDATION
Jorge Gomes, Sin Chan Chou and Gilberto Fisch
Deep convection characteristic parameters from soundings over Rondonia AMC-LBA sites were evaluated and compared with Eta model forecasts. Radiosondes were interpolated to 5hPa regular intervals. The model diurnal cycle captured correctly the observed amplitude and timing. Thermodynamic variables such as CAPE, cloud base and top, cloud lapse rate, deficit from saturation pressure, etc. were calculated from observations and model hourly profile outputs. The model adjusts the convective environment toward a drier profile below the freezing level and toward a moister profile in the levels above. The new parameters derived from the observations were input to the model which produced a reasonable forecast over most part of Brazil. Equitable Threat Score showed significant improvement of precipitation forecasts over most of the domains using new set of parameter, however, the model show little change over the Tropical forest region
Model improvements based on LBA data
CPTEC
SIMULATIONS WITH A RADIATION MODEL AND COMPARISONS WITH LBA DATA SETS
Sergio H. Franchito, E. C. Moraes and V. Brahmananda Rao
The LBA data are used to estimate and validate infrared and solar radiation
models calculations of Chou and Suarez. The models are tested for two
contrasting vegetation regions: forest and grassland. Observed data of
several days and different times of a day collected in the two sites are
used to test the models. The results show that the models simulations in
general agree well with the observations for both the forest and grassland
cases. The mean errors are around the same order or lower than the instrument
errors, except in the case of the reflected solar radiation. The radiation
fluxes are strongly correlated with the observed data, significant at 99%
confidence level, except in the case of the downward longwave radiation.
Model improvements based on LBA data
NASA - DAO
THE MOISTURE BUDGET BI-MODAL PATTERN OF THE SUMMER CIRCULATION OVER SOUTH AMERICA
Dirceu Herdies, Arlindo da Silva, Maria A. F. Silva Dias
The LBA observations during january-february 1999 campaing were
divided into South Atlantic Convergence Zone (SACZ) events and
non-SACZ events. These data were used to validate the DAO/NASA
Global Model analyses. The moisture budget over South America
showed that the moisture transport from tropics to extratropics
is more efficient during SACZ than during Low Level Jet events.
Model improvements based on LBA data