Global oceanic precipitation: A joint view by TOPEX and the

摘要: The TOPEX/POSEIDON mission offers the first opportunity to observe rain cells over ocean by a dual-frequency radar altimeter (TOPEX) and simultaneously their natural radiative properties three-frequency radiometer (TOPEX microwave (TMR)). This work is feasibility study aimed at understanding capability potential of active/passive TOPEX/TMR system for oceanic rainfall detection. On basis past experiences in flagging, joint probability index proposed. integrates several advantages two sensors provides more reliable estimate than alone. One year's TOPEX/ TMR data are used test performance index. resulting frequency statistics show quantitative agreement with those obtained from Comprehensive Ocean-Atmosphere Data Set (COADS) Intertropical Convergence Zone (ITCZ), while qualitative found other regions world ocean. A recent finding that latitudinal precipitation Southern Ocean increases steadily toward Antarctic continent confirmed our result. Annual seasonal maps derived Notable features revealed include an overall similarity pattern Pacific, Atlantic, Indian Oceans general phase reversal between hemispheres, as well number regional anomalies terms intensity. Comparisons simultaneous Global Precipitation Climatology Project (GPCP) multisatellite rate COADS climatology suggest systematic differences also exist. example maximum ITCZ appears be intensive concentrated result compared GPCP. Another annual produced constantly higher GPCP extratropical northern hemisphere, especially northwest Pacific Ocean. Analyses variations prominent rainy dry zones tropics subtropics various behaviors such migration, expansion contraction, merging breakup, pure intensity variations. seasonality largely influenced local atmospheric events monsoon, storm, or snow activities. results this TOPEX its follow-on may serve complementary sensor special microwave/imager observing global precipitation.