Search NASA⌕ Search

Engineering topics

Chao, Y.

Publications and source records attributed to Chao, Y..

65 records · Page 4

Parallel Optimization of an Earth System Model (100 Gigaflops and Beyond?)

We are developing an Earth System Model (ESM) to be used in research aimed to better understand the interactions between the components of the Earth System and to eventually predict their variations. Currently, our ESM includes models of the atmosphere, oceans and the important chemical tracers therein.

Parallel Optimization Earth System Model↗

On the Evolution-Dynamics of Tropical Ocean-Atmosphere Annual-Cycle Variability

The structure of ocean-atmosphere annual-cycle variability across the global tropics is extracted from the Comprehensive Ocean-Atmosphere Data Set (COADS) surface winds and SSTs, and oceanic heat-content simulation from a nonlinear shallow water model (forced by COADS wind stress) using the co-variance based rotated principal component analysis technique.

COADS↗

A Pacific Ocean general circulation model for satellite data assimilation

A tropical Pacific Ocean General Circulation Model (OGCM) to be used in satellite data assimilation studies is described. The transfer of the OGCM from a CYBER-205 at NOAA's Geophysical Fluid Dynamics Laboratory to a CRAY-2 at NASA's Ames Research Center is documented. Two 3-year model integrations from identical initial conditions but performed on those two computers are compared. The model simulations are very similar to each other, as expected, but the simulations performed with the higher-precision CRAY-2 is smoother than that with the lower-precision CYBER-205. The CYBER-205 and CRAY-2 use 32 and 64-bit mantissa arithmetic, respectively. The major features of the oceanic circulation in the tropical Pacific, namely the North Equatorial Current, the North Equatorial Countercurrent, the South Equatorial Current, and the Equatorial Undercurrent, are realistically produced and their seasonal cycles are described. The OGCM provides a powerful tool for study of tropical oceans and for the assimilation of satellite altimetry data.

Chao, Y.↗