Precipitation: A Hydrologic Perspective

1
PrecipitationA Hydrologic Perspective

• Christa D. Peters-Lidard, Ph.D.
• Hydrological Sciences Branch
• NASA/GSFC

2
Hydrologic Applications Spatial and Temporal
Scales
Global
Global Water and Energy Cycle Studies
Conti-nental
Water Resources Management
Space
Regional
Hydrologic Forecasting
Local
Day
Week
Hour
Month
Year
Time
3
Global Precipitation Stations
GPCC data base WMO/GTS data (6328 stations,
July 1987 CLIMATSYNOP)
Source DWD/Global Precipitation Climatology
Centre (GPCC)
4
Issue 1 Bias Over Land
Global Water and Energy Cycle Studies

• Example Radar vs. GSFC Real-time MPA

• Action Produce gauge-adjusted archival-
• quality products with quality metrics

5
Issue 2 Regional/Daily Accuracy
Water Resources Management

• Example Modeled vs. GSFC MPA Daily Correlations

• Action Study and evaluate the impact of
  satellite-based precipitation

6
Issue 3 Local/Diurnal Accuracy
Hydrologic Forecasting

• Example TRMM- based rainfall over
  Haiti/Dominican Republic

• Key Needs
• Sub-diurnal sampling
• Local (1km) estimation
• (e.g., GSFC/LIS)
• Timely delivery (hours)
• Actions
• Short-term Study spatial/temporal precipitation
  downscaling approaches
• Long-term Work towards global cloud-resolving
  models with precipitation assimilation

7
Issue 4 Mission Requirements

• Precipitation mission requirements must take
  advantage of recent work on
• Snowfall estimation
• Multi-sensor rainfall estimation
• Precipitation data assimilation
• Cloud-resolving models
• Action Precipitation Science Team Sponsored
  Workshops/town halls at AMS, AGU

8
Summary

• Issues
• Bias Over Land
• Regional/Daily Accuracy
• Local/Diurnal Accuracy
• Mission Requirements

• Actions
• Precipitation Science Team
• Produce gauge-adjusted archival-quality products
  with quality metrics
• Study impact of satellite-based products
• Work on downscaling/assimilation/CRM
• Sponsored Workshops/town halls at AMS, AGU