A detailed study on global oceanic precipitation is carried out using the simultaneous TOPEX and TMR (TOPEX Microwave Radiometer) data. It is motivated by he success of a series of feasibility studies based on a few years of TOPEX TMR data, and the availability of a deeade-Iong new dataset thai spans I992-2002. In this context, a previously proposed rain probability index is improved by taking into account the dirtfference ol the dynamic range of the TOPEX-measured backscatter coefficients at the Ku and C hands and the lalitudinally complementary sensitivities of the TOPEX and TMR rain detections, leading to a refined joint precipitation index, which is generally consistent and quantitatively comparable with existing precipitation ciimatologies from the Global Preelpitation Climatology Project (GPCP) and the Comprehensive Ocean-Atmosphere Data Set (COADS). The new TOPEX-TMR precipitation climatology, on the one hand. confirms the fundamental features of global oceanic rainfall with additional details, and, on the other hand, reveals a number of interesting characteristics that are previously unknown or pnorly defined. 1) The spatial variability of the western Pacific "rain pool" (the atmospheric counterpart of the oceanic warm pool) is characterized by an interannual zonal migration, an annual cycle of meridional seesaw, and a semiannual cycle of expansion and shrinking. 2) The Pacific, Atlantic, and Indian Ocean interropical convergence zones (ITCZs) all have all annual cycle of cross-basin oscillation with east and west slops in JJA and DJE respectively. 31 A well-defined prominent rainy zone is observed in the southeast China Seas sound Taiwan Island, connecting with the Pacific rain pool in the south. 4) Between El Nifio and La Nina years, there is a systematic sign reversal of the geographical distribution of precipitation anomaly, which exists globally rather than in the tropical oceans only. 5) On a global basis, interannual and annual precipitation variabilities are of the same magnitude, bul the interannual (annual) com-ponent is more important for the Southern (Northern) Hemisphere. 6) For the tropical oceans, "season" defined by rainfall usually has a one quarter delay with respect to the coaesponding meteorological season. For the "'marine deserts" in the subtropical oceans, however, the raln-based season is found to be anticorrelated with the meteorological season. In addition, the annual cycle of the Atlantic precipitation is nearly 180 out of phase with respeet to thin of the Pacific and Indian Ocean for the same hemisphere.