AN EXTENDED DENDROCLIMATIC RECONSTRUCTION FOR THE DOMINICAN REPUBLIC FROM PINUS OCCIDENTALIS

The tropics are a challenging location for tree-ring reconstructions because of the lack of seasonality in temperature and day length, but such reconstructions are vital to efforts to better understand climatic variability near the equator over the past several centuries. Long-term dendroclimatic reconstructions from the tropics are sparse and the Caribbean is particularly underrepresented. In this paper, we present an extended tree-ring climate reconstruction from the Dominican Republic using a subset of 120 sampled Pinus occidentalis trees located above 2800 m elevation on the dry slopes of Loma la Pelona in the Cordillera Central (19º02'07” N, 71º00'19” W). Our chronology, which extends into the 1700s, was crossdated using the skeleton plot method and the dating was checked using the COFECHA quality control program. Climate response of these trees was tested using monthly temperature and precipitation data and with the Palmer Drought Severity Index calculated for meteorological data from the town of Constanza, located at 1160 m elevation 62 km ESE of the sampling site. Climate response was also compared with proxy records of sea surface temperature from Caribbean sites. The chronology correlates positively with rainfall days during the late dormant season on the windward mountain flank, and negatively with early growing season temperature on the leeward flank. The significant relationship with temperature potentially represents one of the few high-resolution (subannual) reconstructions of temperature for a subtropical location. We are now examining this centuries-long chronology for ocean-atmosphere circulation signals associated with the North Atlantic Oscillation, the Tropical Southern Atlantic Index, and the El Niño-Southern Oscillation.