Utilizing the IHOP 2002 data to study variability
in surface water cycle and precipitation process
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F. Chen, M. LeMone, T. Horst, D. Yates, S. Semmer, S.
Trier, K. Manning, M. Tewari, H. McIntyre (NCAR)
R. Grossman (Colorado Research Associates)
R. Cuenca (Oregon State University)
D. Niyogi (North Carolina State University)
P. Blanken, J. Alfieri, J. Uebelherr(University of Colorado)
Motivation
IH2OP surface, vegetation, and soil observation network
Preliminary results
Scientific Issues
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How does land surface (soil moisture,
vegetation, terrain) contribute to the amount
and variation of water vapor in PBL?
 How well the BL structure reflect the
underlying surface conditions
 Under which condition do mesoscale
circulation occur
 How is BL depth affected
How do the above influence convection
initiation and evolution
IHOP Surface, Soil and Vegetation Network
URL:http://www.rap.ucar.edu/projects/land/IHOP/index.htm
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Part of IHOP network to support the ABL mission
Nine NCAR surface-flux stations provide:
 Complete surface energy budget, near-surface
atmospheric conditions, precipitation
 Soil moisture/temperature only at 5 cm depth
Enhance the NCAR surface stations by adding
soil and vegetation instruments
Supported by NCAR Water Initiative
(purchase soil and vegetation sensors, field trips)
Nine NCAR Surface, soil, and vegetation
stations. Plus one (site 10) from CU
Central Leg
Sites 4, 5, 6
Eastern Leg
Sites 7, 8, 9
ABLE
Network
Western Leg
Sites 1, 2, 3
CU station 10
OK Mesonet
Methodology
IHOP
No
1
Land
Cover
WW
Fetch
Lat
Long
10
36 28.370
100 37.075
Elevation
(m)
871
2
CRP grass
9
36 37.327
100 37.619
859
S55 B10 HT and B Survey
(Texas)
SW¼S19T2NR23E
3
9
36 51.662
100 35.670
780
N ¼ S32 T5NR23E
4
Sagebrush
mesquite
cactus
Grass
7-8
37 21.474
98 14.679
509
SE ¼ S12T31S R9W
5
WW
10
37 22.684
98 09.816
506
W ½ S2 T31S R8W
6
WW
10!
37 21.269
97 39.200
417
NW ¼ S16 T31S R3W
7
Grass, grazed
8
37 18.972
96 56.323
382
NE ¼ S36-T31S R4E
8
Grass,
May be burned
Grass,
will
graze cattle.
Heavily
grazed
9
37 24.418
96 45.937
430
SW¼ S27 T30S R6E
8-9,
rolling
9+
37 24.618
96 34.028
447
E½ S30 T30S R8E
36 53.544
100 36.202
9
10
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+
+
Legal
NE ¼ S19T5NR23E (CU site)
Strategically place ten surface stations along the flight
tracks and over different landuse types (range grass, wheat,
sparsely vegetated)
Single profile of soil moisture and temperature sensors at
seven stations: measurements centered at 7.5, 15, 22.5,
37.5, 60, 70-95 cm
Three profiles at Sites 1 and 9 ‘super sites’
Expected Data
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Near-surface weather conditions, PAR, surface incoming and
net radiation (full component at sites 1,8, and 9),
precipitation, surface heat fluxes, ground heat flux
CO2 concentrations at sites 1 and 8
Soil moisture content, soil water tension (potential), and soil
temperature profiles from the surface to a depth of 90 cm
(about seven weeks). Three profiles at sites 1 and 9
Soil bulk density, soil texture, saturated hydraulic
conductivity, unsaturated hydraulic conductivity function,
thermal conductivity, and the soil-water retention function.
Weekly vegetation data: NDVI, LAI, stomatal resistance,
transpiration
Diurnal cycle of stomatal resistance and transpiration for a
few selected sties
Rain accumulation (mm)
West leg
Sites 1, 2, 3
Central leg
Sites 4, 5, 6
East leg
Sites 7, 8, 9
Latent heat flux (W m-2)
Weather Research Forecast(WRF)/ LSM coupled
model verification (with 10-km grid spacing)
31 May 2002
Sites 1, 2, 3
Sites 7, 8, 9
M. Tewari and F. Chen
WRF/LSM coupled model verification
Sites 1, 2, 3
Sites 7, 8, 9
M. Tewari and F. Chen
High-resolution land data assimilation system (HRLDAS)
 Multi-resolution (4, 12 km)
 Utilize:
 4-km hourly NCEP Stage-II; 1-km landuse type and
soil texture maps; 0.5 degree hourly satellite
derived downward solar radiation; T,q, u, v, from
model based analysis;
 To simulate the evolution
of soil moisture and
temperature, evaporation
and runoff.
 Hourly product (Jan-July
2002)
4-km surface soil moisture
Valid at 12 Z May 29 2002
Impact of soil moisture on QPF
3-h rainfall ending 18Z 19 June 1998 (dryline case)
MM5 using soil moisture
from HRLDAS
S. Trier, K. Manning, and F. Chen
MM5 using soil moisture
from NCEP EDAS coarse
resolution and too wet
Important BL processes
for convection initiation and intensification
for the 19 June 1998 dryline case
Quasi-stationary convective rolls
formed at the dryline seem critical
for CI
S. Trier, K. Manning, and F. Chen
Mesoscale circulation formed
as result of differential heating
in the morning may be
responsible for CI in OK
Summary
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Comprehensive atmospheric, soil, and vegetation
data set from IHOP surface/soil/vegetation
network
 Allow a detailed analysis and improvement of
LSM components
 Verify couple model simulation
Study relationships among S-pol water vapor
(Roberts and Wilson), King Air fluxes and water
vapor (LeMone), and HRLDAS soil moisture and
surface evaporation
Investigate the role of convective rolls and
mesoscale circulations in CI and QPF with IHOP
data