Preliminary Report on the 50 year Downscaling of NCEPNCAR

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Preliminary Report on the 50 year Downscaling of NCEPNCAR Powered By Docstoc
					Preliminary Report on the 50 year
 Downscaling of NCEP/NCAR
Reanalysis over California and US
         Masao Kanamitsu
               and
         Hideki Kanamaru
                               Objective
• Global change detection
   – What is the regional scale climatology?
       •   Climatology
       •   Seasonal cycle
       •   Diurnal cycle
       •   Interannual variability
   – Trend. What is changing locally?
       •   Max/Min temperatures
       •   Winds
       •   Snow
       •   Runoff and its timing
       •   Precipitation-Altitude relationship
       •   Occurrence of other significant phenomena
   – Relation with man made land use changes
                Requirement
• Long period analysis (simulations).
  – Accuracy of simulations
• High spatial and temporal resolution
                    CEC related modeling work at Scripps:
                        50-year downscaling project
Downscaling of NCEP/NCAR Reanalysis. 10km resolution, hourly output.

Two runs:
         California region:
                   Running on NCAR IBM-SP, Tera-grid (SDSC, NCSA)
                    40 years complete
         Extended US region:
                   Running on Earth Simulator
                   Production started in May (still simulating first year due to
                   technical problems.
Comparison with NARR
July 2m Temp Climatology
January 10m Wind Climatology
January Precip. Climatology
July 0-200cm Soil Moisture
        Climatology
            New findings

Interannual variability of monthly means
 Standard deviation of monthly averaged
        near surface temperature
(interannual variability of monthly mean)
Corresponding wind field
Interannual Variation of January mean U
          Coastal ocean points
Interannual Variation of January mean U
            Mountain points




    No clear correspondence with ENSO
              Future work
• Complete 50 year 10-km downscaling over
  California and over the continental US
• Verify against NARR and available
  observation
• Make detailed analysis of climatology,
  interannual variability and trend.
• Perform sensitivity studies.
• Improve model (numerics and physics).
END
        July 10m Wind
Climatological Diurnal Variation