1. JPL Technical Activities
NASA Drought Project Meeting
24 April 2007
National Drought Monitoring System for Drought Early Warning Using Hydrologic and Ecologic Observations from NASA Satellite Data
JPL Technical Activities
Presentation by S. V. Nghiem
NASA JPL, California Institute of Technology

2. US Drought Monitor (USDM)
USDM: state-of-the-art drought monitoring system and decision support tool using percentile ranking based on indices/indicators: Palmer drought index, CPC soil moisture model, USGS weekly streamflow, standardized precipitation index (SPI), and satellite vegetation health index …

3. AMSR-E Microwave Radiometer
In support of the Earth Science Enterprise's goals, NASA's Earth Observing System (EOS) Aqua Satellite was launched from Vandenberg AFB, California on May 4, 2002 at 02:54:58 a.m. Pacific Daylight Time. The primary goal of Aqua, as the name implies, is to gather information about water in the Earth's system. Equipped with six state-of-the-art instruments, Aqua will collect data on global precipitation, evaporation, and the cycling of water. This information will help scientists all over the world to better understand the Earth's water cycle and determine if the water cycle is accelerating as a result of climate change.
Table 1. EOS AMSR Nominal Performance Characteristics
—————————————————————————————————————————
Center Frequencies GHz
Bandwidth (MHz)
Sensitivity (K)
IFOV (km) 76 x x x x x 8 6 x 4
Sampling Rate (km) 10 x x x x x 10 5 x 5
Integration Time (ms)
Main Beam Efficiency %
Beamwidth (degrees)

4. AMSR-E Microwave Radiometer
Soil moisture: From simple model by NOAA CPC using surface observations of precipitation and temperature; containing significant uncertainties.
AMSR-E Data:
Aboard EOS Aqua Satellite since 2002
Soil moisture product (gridded Level 3, AE-Land3)
Full US coverage in 3 days at 25-km resolution
Large-scale representation of surface soil moisture
Better in Western US than in Eastern (vegetation)
AMSR-E vegetation water content product is useful

5. AMSR-E Soil Moisture and Vegetation Water Content
August 2002
Soil water content (v/v %):
shows dry conditions in western
U.S., consistent with the drought
conditions there according to
the USDM drought map.
August 2002
Vege. water content (kg·m2):
shows higher vegetation water content in eastern US that may mask soil moisture signature in this area.

6. QuikSCAT Microwave Scatterometer
Scatterometer: stable and accurate RADAR
Launched in June 1999 (8-years data so far)
QuikSCAT: Sun-sync, ~14 orbits per days
Conical scan with all azimuth angles
Cover >90% global/day, 2 times/day hi-lat.
Resolutions: Cell 25x25 km, 7x25 km

7. QuikSCAT Microwave Scatterometer
Standardized Precipitation Index (SPI): Currently used in USDM; based on preliminary precipitation data from stations; rain gauge data are not accurate; 3-4 months to get quality-controlled data.
QuikSCAT Data:
SeaWinds scatterometer on QuikSCAT since 1999
Water on land surface from precipitations
Full US coverage in 2.5 days at 25-km resolution
Monitoring water change and dispersion process
Counting and mapping precipitation frequency
Seasonal trend: Season change of vegetation

8. SCAN Station, Lonoke, Arkansas

9. QuikSCAT and GLDAS Products
9/4/2004
9/5/2005 2 5 10 15 20 25
35 mm 21 27 33 39 45
140
130
120
110
100 90 80 70 60
(a)
(c)
(b)
(d)
(e)
(f)
0.2
0.4
0.6
0.8
1.0
1.2 dB
1.7
3.3
5.0
6.7
8.4
10.0 %
NEXRAD IV
HIGGINS
QuikSCAT

10. QuikSCAT Drought Monitoring
NOAA NCDC/GSOD Station Great Falls, Montana

11. QuikSCAT Result and USDM Comparison
October 12, 2004
October 5, 2004
October 11, 2004

12. (mid-May to mid-September)
QuikSCAT Precipitation-Water Frequency
(mid-May to mid-September)
2000: Sixth wettest June in 106 years, widespread flash floods and long-term river flood in US Midwest.
2003: Severe drought in Iowa, August driest record, soybean production down 25-30% compared to 2002,when productivity had been significantly down compared to that in 2000.

13. QuikSCAT Snowmelt Monitoring Not supported by NASA Drought Project

15. AMSR Stream Flow Measurement
Not supported by NASA Drought Project
Reach 134, Red River, North Dakota
Reach 187, Wabash River, Indiana
Reach 1, Lena River, Russia

16. Summary
Computer upgrade: 10 terabyte RAID, DLT library with robotic arm
AMSR-E level 2 and level 3 data are at JPL
QuikSCAT Mission Project: Decided to reprocess all QuikSCAT backscatter data
Reprocessed QuikSCAT data are being transferred for drought product processing
Output products in binary and ASCII data, and images
Specific formats to be discussed with the NASA Drought Project team