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Ekman's theory of wind-driven ocean currents on a rotating planet is central to our understanding of why surface currents are deflected to the right of the winds in the Northern Hemisphere and to the left of the winds in the Southern Hemisphere. The theory admits solutions for currents deflected in the opposite direction at periods shorter than the local inertial period, but Ekman did not mention these currents, and they have only rarely been observed. Here, we describe a prominent example of surface flow in the Bay of Bengal directed to the left of clockwise-rotating land breeze wind forcing using multiple years of data from a long-term deepwater surface moored buoy. We further refine Ekman's theory so as to better reconcile it with our own and previous measurements and then conclude by discussing the broad implications of this work for understanding wind-forced ocean circulation. [ABSTRACT FROM AUTHOR]

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 Nino and La Nina on biogeochemical cycles. New biological production during the 1997-99 El Nino/La Nina period varied by more than a factor of 2. The resulting interannual changes in global carbon sequestration associated with the El Nino/La Nina cycle contributed to the largest known natural perturbation of the global carbon cycle over these time scales., Interannual fluctuations in the coupled climate system over the tropical Pacific Ocean may induce substantial variability in the global carbon cycle because of effects on biological production in this region [...]

The 1997-98 El Nino was, by some measures, the strongest on record, with major climatic impacts felt around the world. A newly completed tropical Pacific atmosphere-ocean observing system documented this [...]

The Atlantic Niño is characterized by sea surface warming in the equatorial Atlantic, which can trigger La Niña, the cold phase of El Niño-Southern Oscillation (ENSO). Although observations show that the Atlantic Niño has weakened by approximately 30% since the 1970s, its remote influence on ENSO remains strong. Here, we show that this apparent discrepancy is due to the existence of two types of Atlantic Niño with distinct patterns and climatic impacts, which we refer to as the central and eastern Atlantic Niño. Our results show that with equal strength, the central Atlantic Niño has a stronger influence on tropical climate than its eastern counterpart. Meanwhile, the eastern Atlantic Niño has weakened by approximately 50% in recent decades, allowing the central Atlantic Niño to emerge and dominate the remote impact on ENSO. Given the distinct climatic impacts of the two types, it is necessary to distinguish between them and investigate their behaviors and influences on climate in future studies. [ABSTRACT FROM AUTHOR]

The article focuses on the deep-reaching acceleration of the ocean circulation which is mainly induced by a planetary intensification of surface winds since the early 1990s. Topics discussed include wind changes associated with the onset of a negative Pacific decadal oscillation, the use of Mann-Kendall test and examination of the spatial pattern of the acceleration of the global ocean circulation.