Central pacific seabirds and the el nino southern oscillation: 1982 to 1983 perspectives

The breeding chronology and reproductive attempts of the seabird community on Christmas Island in the central Pacific Ocean (2 degrees N, 157 degrees W) were interrupted by the 1982-1983 El Ni?o Southern Oscillation. The resultant reproductive failure and disappearance of the entire seabird community of this equatorial atoll represents the most dramatic interruption on record of a seabird community located distant from coastal upwelling. Our data indicate the effect that the abiotic and biotic aspects of a global atmospheric-oceanic anomaly have on marine birds. The 1982-1983 El Ni?o Southern Oscillation provides an example of selective pressures and a natural experiment in the study of vertebrate population dynamics.     

A theory for el nino and the southern oscillation

A coupled atmosphere-ocean model is presented for El Ni?o and the Southern Oscillation that reproduces its major features, including its recurrence at irregular intervals. The interannual El Ni?o-Southern Oscillation cycle is maintained by deterministic interactions in the tropical Pacific region. Ocean dynamics alter sea-surface temperature, changing the atmospheric heating; the resulting changes in surface wind alter the ocean dynamics. Annually varying mean conditions largely determine the spatial pattern and temporal evolution of El Ni?o events.     

Reduced interannual rainfall variability in East Africa during the last ice age

Interannual rainfall variations in equatorial East Africa are tightly linked to the El Ni?o Southern Oscillation (ENSO), with more rain and flooding during El Ni?o and droughts in La Ni?a years, both having severe impacts on human habitation and food security. Here we report evidence from an annually laminated lake sediment record from southeastern Kenya for interannual to centennial-scale changes in ENSO-related rainfall variability during the last three millennia and for reductions in both the mean rate and the variability of rainfall in East Africa during the Last Glacial period. Climate model simulations support forward extrapolation from these lake sediment data that future warming will intensify the interannual variability of East Africa's rainfall.     

ENSO as an integrating concept in earth science

The El Ni?o-Southern Oscillation (ENSO) cycle of alternating warm El Ni?o and cold La Ni?a events is the dominant year-to-year climate signal on Earth. ENSO originates in the tropical Pacific through interactions between the ocean and the atmosphere, but its environmental and socioeconomic impacts are felt worldwide. Spurred on by the powerful 1997-1998 El Ni?o, efforts to understand the causes and consequences of ENSO have greatly expanded in the past few years. These efforts reveal the breadth of ENSO's influence on the Earth system and the potential to exploit its predictability for societal benefit. However, many intertwined issues regarding ENSO dynamics, impacts, forecasting, and applications remain unresolved. Research to address these issues will not only lead to progress across a broad range of scientific disciplines but also provide an opportunity to educate the public and policy makers about the importance of climate variability and change in the modern world.     

Impacts of a global climate cycle on population dynamics of a migratory songbird

Progress toward understanding factors that limit abundances of migratory birds, including climate change, has been difficult because these species move between diverse locations, often on different continents. For black-throated blue warblers (Dendroica caerulescens), demographic rates in both tropical winter quarters and north temperate breeding grounds varied with fluctuations in the El Ni?o Southern Oscillation. Adult survival and fecundity were lower in El Ni?o years and higher in La Ni?a years. Fecundity, in turn, was positively correlated with subsequent recruitment of new individuals into winter and breeding populations. These findings demonstrate that migratory birds can be affected by shifts in global climate patterns and emphasize the need to know how events throughout the annual cycle interact to determine population size.     

Ecology. Weather ruins winter vacations

There has been increasing concern over the decline in many migratory bird species. As Saether discusses in his Perspective, evidence is accumulating (Sillett et al.) that climate change resulting from the El Ni?o Southern Oscillation affects both the survival rate of adult birds at tropical wintering sites and their reproductive rate at summer breeding grounds in the Northern Hemisphere.     

Oceanographic events during el nino

El Ni?o events, the most spectacular instances of interannual variability in the ocean, have profound consequences for climate and the ocean ecosystem. The 1982-1983 El Ni?o is perhaps the strongest in this century. El Ni?o events usually have followed a predictable pattern, but the recent event differs markedly. The physical oceanography of this El Ni?o is described and compared with that of earlier events.     

Recent variability in the southern oscillation: isotopic results from a tarawa atoll coral

In the western tropical Pacific, the interannual migration of the Indonesian Low convective system causes changes in rainfall that dominate the regional signature of the El Ni?o-Southern Oscillation (ENSO) system. A 96-year oxygen isotope record from a Tarawa Atoll coral (1 degrees N, 172 degrees E) reflects regional convective activity through rainfall-induced salinity changes. This monthly resolution record spans twice the length of the local climatological record and provides a history of ENSO variability comparable in quality with those derived from instrumental climate data. Comparison of this coral record with a historical chronology of EI Ni?o events indicates that climate anomalies in coastal South America are occasionally decoupled from Pacific-wide ENSO extremes. Spectral analysis suggests that the distribution of variance in this record has shifted among annual to interannual periods during the present century, concurrent with observed changes in the strength of the Southern Oscillation.     

Super ENSO and global climate oscillations at millennial time scales

The late Pleistocene history of seawater temperature and salinity variability in the western tropical Pacific warm pool is reconstructed from oxygen isotope (delta18O) and magnesium/calcium composition of planktonic foraminifera. Differentiating the calcite delta18O record into components of temperature and local water delta18O reveals a dominant salinity signal that varied in accord with Dansgaard/Oeschger cycles over Greenland. Salinities were higher at times of high-latitude cooling and were lower during interstadials. The pattern and magnitude of the salinity variations imply shifts in the tropical Pacific ocean/atmosphere system analogous to modern El Ni?o-Southern Oscillation (ENSO). El Ni?o conditions correlate with stadials at high latitudes, whereas La Ni?a conditions correlate with interstadials. Millennial-scale shifts in atmospheric convection away from the western tropical Pacific may explain many paleo-observations, including lower atmospheric CO2, N2O, and CH4 during stadials and patterns of extratropical ocean variability that have tropical source functions that are negatively correlated with El Ni?o.     

Biospheric primary production during an ENSO transition

The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) provides global monthly measurements of both oceanic phytoplankton chlorophyll biomass and light harvesting by land plants. These measurements allowed the comparison of simultaneous ocean and land net primary production (NPP) responses to a major El Ni?o to La Ni?a transition. Between September 1997 and August 2000, biospheric NPP varied by 6 petagrams of carbon per year (from 111 to 117 petagrams of carbon per year). Increases in ocean NPP were pronounced in tropical regions where El Ni?o-Southern Oscillation (ENSO) impacts on upwelling and nutrient availability were greatest. Globally, land NPP did not exhibit a clear ENSO response, although regional changes were substantial.     

Dynamical response of the tropical Pacific Ocean to solar forcing during the early Holocene

We present a high-resolution magnesium/calcium proxy record of Holocene sea surface temperature (SST) from off the west coast of Baja California Sur, Mexico, a region where interannual SST variability is dominated today by the influence of the El Ni?o-Southern Oscillation (ENSO). Temperatures were lowest during the early to middle Holocene, consistent with documented eastern equatorial Pacific cooling and numerical model simulations of orbital forcing into a La Ni?a-like state at that time. The early Holocene SSTs were also characterized by millennial-scale fluctuations that correlate with cosmogenic nuclide proxies of solar variability, with inferred solar minima corresponding to El Ni?o-like (warm) conditions, in apparent agreement with the theoretical "ocean dynamical thermostat" response of ENSO to exogenous radiative forcing.     

Breeding patterns of galapagos penguins as an indicator of oceanographic conditions

Surface water changes associated with El Ni?o have been known to affect deleteriously top carnivores along coastal South America. Data on the breeding strategies of Galápagos penguins and other seabirds indicate that the biological effects of El Ni?o extend much farther west. The breeding biology of these seabirds is adapted to frequent changes in productivity which are associated with El Ni?o.     

Eocene El Niño: evidence for robust tropical dynamics in the "hothouse"

Much uncertainty surrounds the interactions between the El Ni?o-Southern Oscillation (ENSO) and long-term global change. Past periods of extreme global warmth, exemplified by the Eocene (55 to 35 million years ago), provide a good testing ground for theories for this interaction. Here, we compare Eocene coupled climate model simulations with annually resolved variability records preserved in lake sediments. The simulations show Pacific deep-ocean and high-latitude surface warming of approximately 10 degrees C but little change in the tropical thermocline structure, atmosphere-ocean dynamics, and ENSO, in agreement with proxies. This result contrasts with theories linking past and future "hothouse" climates with a shift toward a permanent El Ni?o-like state.     

Length-of-Day Variations Caused by El Nino-Southern Oscillation and Quasi-Biennial Oscillation

Two prominent interannual atmospheric fluctuations, the El Ni?o-Southern Oscillation in the troposphere-ocean system and the Quasi-Biennial Oscillation in the equatorial stratosphere, account for most of the observed interannual length-of-day (LOD) variation from 1964 through 1987, with a relative contribution of about 2 to 1. Thus the atmosphere-LOD connection extends from seasonal and shorter periods to interannual periods up to about 10 years.     

Elimination of two reef-building hydrocorals following the 1982-83 el nino warming event

One probable extinction and one range reduction of eastern Pacific reef-building hydrocoral (Millepora) species mark the first documented cases of species eliminations resulting from the worldwide 1980s coral reef bleaching events. Two of 12 Panamanian coral species were eliminated suddenly from their former ranges by prolonged high sea temperatures during the 1982-83 El Ni?o-Southern Oscillation event. Three conditions contributed to their demise: high sensitivity to sea warming, populations confined to a small geographic area, and bathymetric restriction to the euphotic zone (相似文献   

全球气候异常（ENSO事件的发生）对我国褐飞虱大发生的影响

 通过对30多年来ENSO事件的发生与我国褐飞虱发生关系的研究，探讨全球气候异常对我国褐飞虱迁飞和种群发展动态的影响。结果表明：在南方涛动强烈异常的当年，我国褐飞虱将为大发生年；在厄尔尼诺或反厄尔尼诺事件的当年，为中到大发生年；在ENSO事件的间歇期，为轻发生年。     

Climatic anomalies in the tropical pacific ocean and corn yields in the United States

The association between climatic anomalies in the tropical Pacific Ocean, often called El Ni?o events, and annual corn production in the United States was investigated. Temperature and atmospheric pressure in parts of the United States have been correlated with El Ni?o events. This research suggests that in years in which an El Ni?o event causes surface temperatures in the tropical Pacific to become warmer than normal, there is a higher probability of an above-average corn crop in the United States. For years when sea surface temperatures are average or cool, no significant association is observed.     

Deep ocean impact of a Madden-Julian oscillation observed by Argo floats

Using the new Argo array of profiling floats that gives unprecedented space-time coverage of the upper 2000 meters of the global ocean, we present definitive evidence of a deep tropical ocean component of the Madden-Julian Oscillation (MJO). The surface wind stress anomalies associated with the MJO force eastward-propagating oceanic equatorial Kelvin waves that extend downward to 1500 meters. The amplitude of the deep ocean anomalies is up to six times the amplitude of the observed annual cycle. This deep ocean sink of energy input from the wind is potentially important for understanding phenomena such as El Ni?o-Southern Oscillation and for interpreting deep ocean measurements made from ships.     

Unraveling the mystery of Indian monsoon failure during El Niño

The 132-year historical rainfall record reveals that severe droughts in India have always been accompanied by El Ni?o events. Yet El Ni?o events have not always produced severe droughts. We show that El Ni?o events with the warmest sea surface temperature (SST) anomalies in the central equatorial Pacific are more effective in focusing drought-producing subsidence over India than events with the warmest SSTs in the eastern equatorial Pacific. The physical basis for such different impacts is established using atmospheric general circulation model experiments forced with idealized tropical Pacific warmings. These findings have important implications for Indian monsoon forecasting.