Traditionally, the tropical zone is known as the "heat reservoir" of the ocean and the "firebox" of the atmosphere. The western equatorial Pacific has been identified as both the warmest portion of the heat reservoir, named "warm pool" (WP), and the hottest portion of the firebox where a huge amount of precipitation-induced latent-heat release is accumulated. The latter mirrors a fact that the western tropical Pacific is also the wettest area on the globe, termed "rain pool" (RP), where the maximum annual precipitation is observed. The accumulation of continuous satellite data has reached a point that decade-long simultaneous observations of many important geophysical parameters have become available in recent years. One such example is the availability of a concurrent dataset of sea surface temperature, oceanic precipitation, and sea surface wind field for 1993-2002 derived from NOAA/AVHRR (Advanced Very High Resolution Radiometer), TOPEX/TMR (TOPEX Microwave Radiometer), and ERS-1,2/QuikSCAT, respectively. In the present study, this dataset is used to demonstrate and investigate the coupling and covarying effects of the Pacific WP and RP, leading to a number of interesting findings on their structural similarity, locational shift, phase lag, and evolutional coherency in association with the development of and the vacillation between El Nino and La Nina events.

The documentation of the zonal pattern of global wind system can be traced back to centuries ago. The prevailing descriptions in most oceanography books, however, have been of little change during the past decades. The present work represents a new effort to update our knowledge on this issue using the newly available multi-year TOPEX altimeter data. As a result, the positions and intensities of major zonal features of the marine wind system are reexamined and more precisely defined. The seasonal, annual, and interannual variabilities of these features in terms of both amplitude and phase are analyzed in detail. Uncertainties associated with the estimated intensity and the peak/trough positions of the zonal wind belts are discussed. Meanwhile, a possible connection between the meridional shift of the Pacific doldrums and the occurrence of an El Nino event is observed.

A detailed analysis on the effect of temporal allaying associated with TOPEX/Poseidon, Geosat, and ERS altimeters has been caried out. In the time domain, aliasing occurs when the original period of an oceanographic signal, To, is less than twice the satellite repeat orbit period, Ts. The most striking feature of temporal aliasing is that the alias period, To, appears as a quasi periodic &llke function with respect to Ts, and a non-periodic &-like function with respect to To. Histograms of Ta versus To suggest that signals wltb original periods between 0 and 2Ts are aliased onto periods ranging from 2Ts to with a rapidly decreasing probabilit3z The potential consequences of temporal aliasing in satellite altimetry are discussed in the context of orbit design and sampling strategy for geophysical applications.

The availability of muhiple sateilite missions with wind measuring capacity has made it more desirable than ever before to integrule wind data from various sources in order to achieve an improved accuracy, resolution. and duration. A clear understanding of the error charaeterlsties associated with each type of data is needed for a meaningful merging or combination. The two kinds of errors-namely, random error and systematic error-ate expected to evolve differently with increasing volume of available data In this study, a collocated ocean Topography Experiment (TOPEX)-NASA Seatterometer (NSCAT)-ECMWF dataset, which covers 66S-66N and spans the entire 10-month lifetime of NSCAT. is compiled to investigate the systematic discrepancies among the three kinds of wind estimates, yielding a number of interesting results, First, the satellite derived wind speeds are found to have a larger overall bias but a much smaller ovemli foot-mean-square (rms) error compared to ECMWF winds, implying thai they are highly converging but are systemalically biased. Second. the TOPEX and NSCAT wind speed biases are characterized by a significant "'phase opposition" with latitude, seasnn, and wind intensity, respectively. Third. the TOPEX (NSCAT) bias exhibits a low-high-low <high-low-high) pattern as a function of wind speed, whose turning poim at 14.2ms-1 coincides well with the transitional wind speed flora swell dominance to wind sea dominance in wave condition, suggesting that the degreee of wave development plays a key role in shaping wind speed bias.

Using the newly available TOPEX Microwave Radiometer (TMR) data spanning 1993 through 2002. a 10 yr climatology of oceanic water vapor [OWVI is constructed, of which the distribution and variation at various spatial-temporal scales we investigated The new dataaet confirms most of the well-known OWV features, and yields a number of interesting findings, due to its high quality, long duration, and unique orbit. I) The TMR-derived climatology compares well in both overall pattern and general statistics, with similar results based on radiosondes and other satellites. Climatological comparisons with sea surface temperature and oceanic precip itation suggest thai the western Pacific warm pool is "mirrored" in the atmosphere as a "'wet pool," whereas the meteorological equator is refleclcd in OWV as a Iransocean equatorial wet belt. 21 It is lound that El Nifio (La Nifia) events are accompanied by a significant increase (decease) in the amount of OWV between 10s and 10N with a somewhat unexpected Southern Hemisphere dominance. This is parieularly evidem during the 1997198 El Nino when the interannual variability of OWV reaches a record high. Composite maps of annual OWV anomalies disclose a dipnlelike pattern in the western equatorial Pacific with a phase opposition between El Nino and La Nina years. 3) The annual amplitude of OWV is characterized by six cross-continent wet belts located largely in the subtropics of both hemispheres. The phase patterns of the annual and semiannual variations are hemispherically divided, and climatologically co.elated, respectively. North (south) of the intertropical convergence zone (ITCZ), a majorily of the oceanic areas have their water vapor maximum in August (February). Early peaks in July are found over a few continental shelf regions of the Northern t-lemisphere (NH), while late peaks in March are fouiid in the tropical oceans of the Southern Hemisphere (SHh Moreover. two delayed maximums in September are visible in the interior North Pacific and North Adandtic, respectively. 4) The daily cycle of OWV is strongly eoupled with its seasonal cycle, and is therefore unstable in nature But a double peak streture with a general hemispheric phase reversal can still be identified. 5) The ratio of the NH versus SH OWV is roughly 1.17:1, and tile relative importance of the interannuah annual, semiannuah diurnal, and semidlurnal variations in terms of mean amplitude is approximately I.fi:5:1.2:1:1. [n view of these encouraging results, further exploration of present and future "attlmele-borne" radiomeler data will no, doubt lead to an improved and complementary understanding of the OWV system in many aspecls.