TOGA COARE: The Coupled Ocean—Atmosphere Response Experiment

Abstract

Despite significant progress in the Tropical Ocean-Global Atmosphere (TOGA) program, a number of major hurdles remain before the primary objective, prediction of the variability of the coupled ocean-atmosphere system on time scales of months to years, can be achieved. Foremost among these hurdles is understanding the physics that maintains and perturbs the western Pacific warm pool, the region of the warmest sea surface temperature in the open oceans, which coexists with the largest annual precipitation and latent heat release in the atmosphere. Even though it is believed that the warm pool is a "center of action" for the El Nino-Southern Oscillation (ENSO) phenomena in the ocean and the atmosphere, successful simulation of the warm pool has remained an elusive goal.To gain a clear understanding of global climate change, the ENSO phenomenon, and the intraseasonal variability of the coupled atmosphere-ocean system, it is clear that a better specification of the coupling of the ocean and the atmosphere is required. An observational and modeling program, the TOGA Coupled OceanAtmosphere Response Experiment (TOGA COARE), has been designed to work toward this goal.The scientific goals of COARE are to describe and understand: 1) the principal processes responsible for the coupling of the ocean and the atmosphere in the western Pacific warm-pool system;2) the principal atmospheric processes that organize convection in the warm-pool region;3) the oceanic response to combined buoyancy and wind-stress forcing in the western Pacific warm-pool region; and 4) the multiple-scale interactions that extend the oceanic and atmospheric influence of the western Pacific warm-pool system to other regions and vice versa.To carry out the goals of TOGA COARE, three components of a major field experiment have been defined: interface, atmospheric, and oceanographic. An intensive observation period (IOP), embedded in a period of enhanced meteorological and oceanographic monitoring, will occur from November 1992 through February 1993 in the western Pacific region bordered by 10°N, 10°S, 140°E, and the date line. The experimental design calls for a complex set of oceanographic and meteorological observations from a variety of platforms that will carry out remote and in situ measurements. The focus of the observational effort will be in an intensive flux array (I FA) centered at 2°S and 156°E. The resulting high-quality dataset is required for the calculation of the interfacial fluxes of heat, momentum, and moisture, and to provide ground truth for a wide range of remotely sensed variables for the calibration of satellite-derived algorithms. The ultimate objective of the COARE dataset is to improve air-sea *Program in Atmospheric and Oceanic Sciences, University of Colorado, Boulder, Colorado + Department of Oceanography, Honolulu, University of Hawaii ©1992 American Meteorological Society interaction and boundary-layer parameterizations in models of the ocean and the atmosphere, and to validate coupled models.

Tropical Pacific near‐surface currents estimated from altimeter, wind, and drifter data

“…Daily mean currents were calculated and passed through a 21 day running mean filter to provide some smoothing of instability wave variability [Halpern et al, 1988]. A 6 month long current record during TOGA COARE [Webster and Lukas, 1992] …”

Diurnal cycle of rainfall and surface salinity in the Western Pacific Warm Pool

“…During this period the TAO array was enhanced as a part of the Coupled Ocean Atmosphere Response Experiment (COARE) [Webster and Lukas, 1992]. Figure I shows the sites used in this study Standard measurements on all TAO moorings include hourly wind speed and direction, air temperature, relative humidity, and SST ].…”

Modelling convective processes during the suppressed phase of a Madden–Julian oscillation: Comparing single‐column models with cloud‐resolving models

“…In order to understand the deficiencies in the representations of convective processes in GCMs and, in particular, their ability to simulate tropical variability, the present case study includes both suppressed and active periods of tropical deep convection, as well as the transitions from suppressed to active periods during the suppressed phase of the Madden-Julian oscillation (MJO), which has a period of 40-50 days (Madden and Julian, 1972). This case study takes advantage of the high-quality dataset from the Tropical Ocean and Global Atmosphere (TOGA) Coupled Ocean-Atmosphere Response Experiment (COARE; Webster and Lukas, 1992) intensive observation period (IOP), during which multiple MJOs were observed.…”