Caribbean sea surface temperatures: Two-to-three degrees cooler than present during the Little Ice Age

We determined the seasonal environmental conditions during the Little Ice Age (LIA) by interpreting isotope proxies in the coral skeleton of Montastrea faveolata from the northeast Caribbean. The oxygen isotope composition was determined for three time intervals during the LIA (1700–1705, 1780–1785, 1810–1815), thought to correspond to the coldest intervals. The period 1984–1989 was used to represent modern calibration conditions. We determined that SSTs from the LIA intervals are nearly 2–3°C cooler than present. LIA cooling in the Caribbean may have resulted from regional oceanic and atmospheric circulation differences, especially in winter. We propose that a trough of cold air from the north Atlantic may have extended farther south than present, into the northern Caribbean. Although there are indications from Pacific corals that seasonality was greater during the LIA, this does not seem to be the case for the Caribbean.