The glacial-interglacial history of tropical climate is controversial. The record from marine sediments in the tropics suggests that there has been little change in atmospheric temperature in these regions. On the other hand the climate record from tropical highlands documents that snowlines, glaciers and treelines were all at lower elevation during the last glaciation. These elevation changes translate into 5 to 6 degree lower surface temperatures in the glacial tropics. The discrepancies may be resolved with better paleoclimate proxies for lowland tropical locations. Unfortunately it is difficult to work on tropical samples because some traditional paleoclimate indices, like tree rings, are not related to tropical climate in a simple way. This proposal suggests an alternative methodology which may provide paleoclimate records on the basis of wood anatomy. The basis for the methodology is that wood porosity will vary as a function of climate. The proposal requests support to test the theory in a study area along the western coast of Costa Rica. Although it is a high risk proposal, it is important because it may provide a new, reliable method for reconstructing climate in tropical locales.
