NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Continental-scale river flow in climate modelsThe hydrologic cycle is a major part of the global climate system. There is an atmospheric flux of water from the ocean surface to the continents. The cycle is closed by return flow in rivers. In this paper a river routing model is developed to use with grid box climate models for the whole earth. The routing model needs an algorithm for the river mass flow and a river direction file, which has been compiled for 4 deg x 5 deg and 2 deg x 2.5 deg resolutions. River basins are defined by the direction files. The river flow leaving each grid box depends on river and lake mass, downstream distance, and an effective flow speed that depends on topography. As input the routing model uses monthly land source runoff from a 5-yr simulation of the NASA/GISS atmospheric climate model (Hansen et al.). The land source runoff from the 4 deg x 5 deg resolution model is quartered onto a 2 deg x 2.5 deg grid, and the effect of grid resolution is examined. Monthly flow at the mouth of the world's major rivers is compared with observations, and a global error function for river flow is used to evaluate the routing model and its sensitivity to physical parameters. Three basinwide parameters are introduced: the river length weighted by source runoff, the turnover rate, and the basinwide speed. Although the values of these parameters depend on the resolution at which the rivers are defined, the values should converge as the grid resolution becomes finer. When the routing scheme described here is coupled with a climate model's source runoff, it provides the basis for closing the hydrologic cycle in coupled atmosphere-ocean models by realistically allowing water to return to the ocean at the correct location and with the proper magnitude and timing.
Document ID
19940038873
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Miller, James R.
(Rutgers Univ. New Brunswick, NJ, United States)
Russell, Gary L.
(NASA Goddard, Greenbelt, MD United States)
Caliri, Guilherme
(Hughes STX Corporation New York, NY, United States)
Date Acquired
August 16, 2013
Publication Date
June 1, 1994
Publication Information
Publication: Journal of Climate
Volume: 7
Issue: 6
ISSN: 0894-8755
Subject Category
Meteorology And Climatology
Accession Number
94A62322
Distribution Limits
Public
Copyright
Other

Available Downloads

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