Dataset Information

Ecosystem responses in the southern Caribbean Sea to global climate change.

ABSTRACT: Over the last few decades, rising greenhouse gas emissions have promoted poleward expansion of the large-scale atmospheric Hadley circulation that dominates the Tropics, thereby affecting behavior of the Intertropical Convergence Zone (ITCZ) and North Atlantic Oscillation (NAO). Expression of these changes in tropical marine ecosystems is poorly understood because of sparse observational datasets. We link contemporary ecological changes in the southern Caribbean Sea to global climate change indices. Monthly observations from the CARIACO Ocean Time-Series between 1996 and 2010 document significant decadal scale trends, including a net sea surface temperature (SST) rise of ?1.0 ± 0.14 °C (±SE), intensified stratification, reduced delivery of upwelled nutrients to surface waters, and diminished phytoplankton bloom intensities evident as overall declines in chlorophyll a concentrations (?Chla = -2.8 ± 0.5%?y(-1)) and net primary production (?NPP = -1.5 ± 0.3%?y(-1)). Additionally, phytoplankton taxon dominance shifted from diatoms, dinoflagellates, and coccolithophorids to smaller taxa after 2004, whereas mesozooplankton biomass increased and commercial landings of planktivorous sardines collapsed. Collectively, our results reveal an ecological state change in this planktonic system. The weakening trend in Trade Winds (-1.9 ± 0.3%?y(-1)) and dependent local variables are largely explained by trends in two climatic indices, namely the northward migration of the Azores High pressure center (descending branch of Hadley cell) by 1.12 ± 0.42°N latitude and the northeasterly progression of the ITCZ Atlantic centroid (ascending branch of Hadley cell), the March position of which shifted by about 800 km between 1996 and 2009.

SUBMITTER: Taylor GT

PROVIDER: S-EPMC3511065 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Ecosystem responses in the southern Caribbean Sea to global climate change.

Taylor Gordon T GT Muller-Karger Frank E FE Thunell Robert C RC Scranton Mary I MI Astor Yrene Y Varela Ramon R Ghinaglia Luis Troccoli LT Lorenzoni Laura L Fanning Kent A KA Hameed Sultan S Doherty Owen O

Proceedings of the National Academy of Sciences of the United States of America 20121015 47

Over the last few decades, rising greenhouse gas emissions have promoted poleward expansion of the large-scale atmospheric Hadley circulation that dominates the Tropics, thereby affecting behavior of the Intertropical Convergence Zone (ITCZ) and North Atlantic Oscillation (NAO). Expression of these changes in tropical marine ecosystems is poorly understood because of sparse observational datasets. We link contemporary ecological changes in the southern Caribbean Sea to global climate change indi ...[more]

PMID: 23071299

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Dataset Information

Ecosystem responses in the southern Caribbean Sea to global climate change.

Publications

Ecosystem responses in the southern Caribbean Sea to global climate change.

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