Feedback relations and causal orders between sea surface temperature and convection within the western Pacific warm pool

Analysis of time series of standardized anomalies of sea surface temperature and outgoing longwave radiation from the western Pacific warm pool revealed two distinct modes of atmosphere-ocean interaction. A statistically binding positive feedback relationship between convection and ocean temperature exists over the equatorial region surrounding the international date line. Here, the contemporaneous feedback between the/se two variables is not statistically significant. A causal order from the ocean temperature to outgoing longwave radiation is detected in a region of the Southwest Pacific, where ocean patches with temperatures greater than or equal to 29.75° C form most frequently. Dynamical implications associated with the aforementioned feedback relationship and causal order are illustrated by estimating the impact of a sudden transient LTJ.crease in convection on future values of sea surface temperature and vice versa

An examination of the 4 March 1999 blizzard

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Evidence of Secular Changes in Rainfall Data from the Tropical Western and Central Pacific over a 20-year Period

Rainfall data from the tropical western and central Pacific over the period from 1971 to 1990 show both decadal and interannual variability. A statistically significant secular trend may be used to model the overall rainfall variability. However, locally weighted regression analysis reveals that this increasing trend stalls in the early 1980\u27 s, and reverses its course by the year 1990. Decomposition of individual rainfall time series into low frequency, seasonal, and irregular components facilitates the isolation of the time varying annual cycle and the elucidation of the interannual signal. Strong or prolonged warm EI Nino-Southern Oscillation events dominate the interannual variability during the study period. The decadal scale variation in the annual cycle is so systematic, in fact, there is approximately a 20% reduction in its amplitude between 1971 and 1982. In addition, the long-term change in the seasonal component appears to modulate the much shorter-term interannual signal

Tropical Wind Stress from Time-Averaged Winds

Oceanwide direct measurement of the surface wind stress is impracticable; instead, the wind stress must be parameterized in terms of individual shipboard wind reports. The number of ship observations, however, are insufficient over the tropical oceans for an adequate analysis of the wind stress. A method is developed to take advantage of the monthly mean wind field which can be determined by meshing several sources of data with the ship observations. It is shown that a single empirical correction factor can be used to estimate the surface pseudostress from monthly mean winds for all months throughout the oceanic tropics