RESUMO
A combination of ship, buoy, and satellite observations in the tropical Pacific during the period from 1992 to 2000 provides a basin-scale perspective on the net effects of El Niño and La Niña on biogeochemical cycles. New biological production during the 1997-99 El Niño/La Niña period varied by more than a factor of 2. The resulting interannual changes in global carbon sequestration associated with the El Niño/La Niña cycle contributed to the largest known natural perturbation of the global carbon cycle over these time scales.
Assuntos
Biomassa , Carbono/metabolismo , Fitoplâncton/metabolismo , Clima Tropical , Atmosfera , Dióxido de Carbono , Oceano Pacífico , Comunicações Via Satélite , TemperaturaRESUMO
A coupled ocean-atmosphere data assimilation procedure yields improved forecasts of El Niño for the 1980s compared with previous forecasting procedures. As in earlier forecasts with the same model, no oceanic data were used, and only wind information was assimilated. The improvement is attributed to the explicit consideration of air-sea interaction in the initialization. These results suggest that EI Niño is more predictable than previously estimated, but that predictability may vary on decadal or longer time scales. This procedure also eliminates the well-known spring barrier to EI Niño prediction, which implies that it may not be intrinsic to the real climate system.
RESUMO
Upwelling in the Costa Rica Dome is seasonal and the result of the localized cyclonic wind stress curl. Fluctuations in the wind stress curl in the fall release the upwelled region as a Rossby wave. Similar low-latitude domes are hypothesized to be ubiquitous to those oceans where a localized cyclonic wind stress curl is associated with an Intertropical Convergence Zone.