Historical Climate Variation in Belize (Central America) as Recorded in Scleractinian Coral Skeletons

Abstract

Abstract Three cores from the scleractinian coral Montastraea faveolata and one core from the scleractinian coral Siderastrea siderea from the Belize barrier and atoll reef complex, Central America, were analyzed with regard to sclerochronology (skeletal extension rates) and stable isotope geochemistry (δ18O and δ13C). The core material covers the time span from 1815 to 2000. The four coral time series were compared with available instrumental climate data, such as sea surface temperatures (GISST), cloud cover (GHCN), and precipitation (COADS). Skeletal extension rates measured in the cores average 8.5–14 mm/year in M. faveolata and 8 mm/year in S. siderea. No systematic correlations between extension rates and instrumental climate data were detected. Annual variation in oxygen isotopes is 0.6– 0.8‰, which accounts for monthly averages of sea-surface water temperature fluctuations of 3–4°C. In three cores from the Belize shelf and barrier reef, negative correlations of δ18O with the GISST 2.3b data were o...