The Tropical Western Pacific: Status report

The Atmospheric Radiation Measurement (ARM) Program's Tropical Western Pacific (TWP) locale is the second of the five primary Cloud and Radiation Testbeds (CART) to be established. Phase implementation is currently planned to begin in 1994. The TWP locale encompasses an immense region of the tropical western Pacific bounded roughly by 10 degrees N to 10 degrees S extending eastward from Indonesia to somewhat east of the international dateline. Climatogically, it is characterized by warm sea surface temperatures, deep and frequent atmospheric convection, high rain rates, strong coupling between the atmosphere and ocean, and substantial variability associated with the El Nino-Southern Oscillation (ENSO) phenomenon. Any number of diagnostic studies can be cited that show the relationship between climatic variability in this region, particularly ENSO, and variability in other parts of the planet. Geographically, this locale is characterized by the maritime continent area in the southwest portion and essentially open ocean in the northeast portion. Details on the locale and the scientific challenges are presented in the proceedings of the second ARM Science Team meeting held in Denver in October 1991 (Clements et al. 1992). The purpose of this paper is to report on activities since the 1991 Science Team meeting and discusses future plans