NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Alternative Approaches to Land Initialization for Seasonal Precipitation and Temperature ForecastsThe seasonal prediction system of the NASA Global Modeling and Assimilation Office is used to generate ensembles of summer forecasts utilizing realistic soil moisture initialization. To derive the realistic land states, we drive offline the system's land model with realistic meteorological forcing over the period 1979-1993 (in cooperation with the Global Land Data Assimilation System project at GSFC) and then extract the state variables' values on the chosen forecast start dates. A parallel series of forecast ensembles is performed with a random (though climatologically consistent) set of land initial conditions; by comparing the two sets of ensembles, we can isolate the impact of land initialization on forecast skill from that of the imposed SSTs. The base initialization experiment is supplemented with several forecast ensembles that use alternative initialization techniques. One ensemble addresses the impact of minimizing climate drift in the system through the scaling of the initial conditions, and another is designed to isolate the importance of the precipitation signal from that of all other signals in the antecedent offline forcing. A third ensemble includes a more realistic initialization of the atmosphere along with the land initialization. The impact of each variation on forecast skill is quantified.
Document ID
20040081366
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
Koster, Randal
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Suarez, Max
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Liu, Ping
(Science Applications International Corp. Greenbelt, MD, United States)
Jambor, Urszula
(Maryland Univ. Greenbelt, MD, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2004
Subject Category
Meteorology And Climatology
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Available Downloads

There are no available downloads for this record.
No Preview Available