Caribbean Corals in Crisis: Record Thermal Stress, Bleaching, and Mortality in 2005

Coral Reef Watch, National Oceanic and Atmospheric Administration, Silver Spring, Maryland, USA.
PLoS ONE (Impact Factor: 3.53). 11/2010; 5(11):e13969. DOI: 10.1371/journal.pone.0013969
Source: PubMed

ABSTRACT The rising temperature of the world's oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin.
Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the timing and location of researchers' field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles.
Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch's Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate.

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Available from: Michael James C Crabbe, Aug 22, 2015
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    • "c o m / l o c a t e / j m a r s y s produced the most severe and extensive mass coral-bleaching event ever recorded in the region. The repeated coral bleaching events in the Caribbean Sea since the 1980's have been broadly attributed to anthropogenic climate change (Eakin et al., 2010; van Hooidonk et al., 2013; van Hooidonk et al., submitted for publication). "
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    ABSTRACT: This study examines the potential impact of anthropogenic greenhouse warming on the Intra-Americas Sea (IAS, Caribbean Sea and Gulf of Mexico) by downscaling the Coupled Model Intercomparison Project phase-5 (CMIP5) model simulations under historical and two future emission scenarios using an eddy-resolving resolution regional ocean model. The simulated volume transport by the western boundary current system in the IAS, including the Caribbean Current, Yucatan Current and Loop Current (LC), is reduced by 20-25% during the 21st century, consistent with a similar rate of reduction in the Atlantic Meridional Overturning Circulation (AMOC). The effect of the LC in the present climate is to warm the Gulf of Mexico (GoM). Therefore, the reduced LC and the associated weakening of the warm transient LC eddies have a cooling impact in the GoM, particularly during boreal spring in the northern deep basin, in agreement with an earlier dynamic downscaling study. In contrast to the reduced warming in the northern deep GoM, the downscaled model predicts an intense warming in the shallow (≤ 200 m) northeastern shelf of the GoM especially during boreal summer since there is no effective mechanism to dissipate the increased surface heating. Potential implications of the regionally distinctive warming trend pattern in the GoM on the marine ecosystems and hurricane intensifications during landfall are discussed. This study also explores the effects of 20th century warming and climate variability in the IAS using the regional ocean model forced with observed surface flux fields. The main modes of sea surface temperature variability in the IAS are linked to the Atlantic Multidecadal Oscillation and a meridional dipole pattern between the GoM and Caribbean Sea. It is also shown that variability of the IAS western boundary current system in the 20th century is largely driven by wind stress curl in the Sverdrup interior and the AMOC.
    Journal of Marine Systems 08/2015; 148:56-69. DOI:10.1016/j.jmarsys.2015.01.007 · 2.48 Impact Factor
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    • "The most severe bleaching event ever recorded in the Caribbean occurred in 2005 due to high ocean temperatures in the tropical Atlantic and Caribbean Sea. During this event, 80% of corals by area were affected by bleaching and 40% died at many locations across 22 countries (Eakin et al., 2010). Coral reefs provide numerous goods and services such as coastal protection and can be critically important to livelihoods. "
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    ABSTRACT: Projections of climate change impacts on coral reefs produced at the coarse resolution (~1°) of Global Climate Models (GCMs) have informed debate but have not helped target local management actions. Here, projections of the onset of annual coral bleaching conditions in the Caribbean under Representative Concentration Pathway (RCP) 8.5 are produced using an ensemble of 33 Coupled Model Intercomparison Project phase-5 models and via dynamical and statistical downscaling. A high-resolution (~11 km) regional ocean model (MOM4.1) is used for the dynamical downscaling. For statistical downscaling, sea surface temperature (SST) means and annual cycles in all the GCMs are replaced with observed data from the ~4-km NOAA Pathfinder SST dataset. Spatial patterns in all three projections are broadly similar; the average year for the onset of annual severe bleaching is 2040-2043 for all projections. However, downscaled projections show many locations where the onset of annual severe bleaching (ASB) varies 10 or more years within a single GCM grid cell. Managers in locations where this applies (e.g., Florida, Turks and Caicos, Puerto Rico, and the Dominican Republic, among others) can identify locations that represent relative albeit temporary refugia. Both downscaled projections are different for the Bahamas compared to the GCM projections. The dynamically downscaled projections suggest an earlier onset of ASB linked to projected changes in regional currents, a feature not resolved in GCMs. This result demonstrates the value of dynamical downscaling for this application and means statistically downscaled projections have to be interpreted with caution. However, aside from west of Andros Island, the projections for the two types of downscaling are mostly aligned; projected onset of ASB is within ±10 years for 72% of the reef locations. © 2015 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
    Global Change Biology 04/2015; DOI:10.1111/gcb.12901 · 8.22 Impact Factor
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    • "Anomalously warm water temperatures have been observed to be one of the major causes of mass coral bleaching worldwide (Munday et al., 2009; Eakin et al., 2010). Critical water temperatures (30–31 • C), duration extent (hours, days, or weeks) and event intensity (Berkelmans and Willis, 1999; Craig et al., 2001; Vargas-Angel et al., 2001; Berkelmans, 2002; Sammarco et al., 2006) are all known to affect coral bleaching (Berkelmans and Willis, 1999; Reaser et al., 2000; Eakin et al., 2010; Bastidas et al., 2012). Coral often dies after having been partially or totally bleached for long periods (Crabbe, 2008). "
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    Ecological Modelling 10/2014; 289:1–14. DOI:10.1016/j.ecolmodel.2014.06.014 · 2.07 Impact Factor
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