Coral-based reconstructions of southern Caribbean climate during the mid- to late Holocene

Abstract

Knowledge about climate variability is essentially based on observational climate data that are often too short to fully understand the underlying mechanisms with sufficient accuracy. Instrumental records of climate are sparse and become spatiotemporally incomplete before the middle of the 20th century thus, limiting our understanding of the Earth s climate system prior to the instrumental data period. Recent changes in climate are often attributed to anthropogenic global warming. However, to validate such an assumption, patterns of climate variability must be firmly established for periods of reduced anthropogenic forcing. The reconstruction of key climate parameters, such as sea surface temperature (SST) and salinity (SSS), in records extending beyond the relatively short instrumental period are a prerequisite. Additionally, since the reconstructions from climate archives usually focused on the long-term changes (i.e., centennial to millennial scales), there is a clear need to better understand the patterns of short-term (i.e., seasonal to multidecadal scales) climate variability, which are often overlooked in paleoclimatology but relevant for the predictability of hazardous climate phenomena. The aim of the present study is to document the natural range of short-term climate variability in the tropical Atlantic during periods of reduced human activity. Analyses were conducted on several annually-banded Diploria strigosa (Dana, 1846) fossil coral colonies of Holocene age found in the coastal deposits on Bonaire (southern Caribbean Sea).