Simulating Tropical Paleoglaciers

Overview

Tropical glaciers are sensitive indicators of high-elevation, low-latitude, climate dynamics on various timescales. Abandoned moraines of the last ice age have long been recognized as evidence of the warming that attended the close of that period. Advances in field mapping, remote sensing and geospatial data processing offer opportunities to refine the spatial and temporal precision of the geologic record of past glacier changes, but there remains a lack of modeling techniques suitable for testing climate hypotheses about observed glacier changes. Glacier changes during the Last Glacial Maximum (LGM) are of particular interest because reconciling relatively large tropical LGM snowline depressions with paleoclimatic proxies that indicate only minor tropical sea surface temperature changes has presented a problem for climate scientists. This collaborative and interdisciplinary project will provide refined LGM paleoclimate estimates for key tropical mountain areas. A 2-D (map view) coupled glacier mass balance and glacier flow model will be specifically adapted to tropical conditions. High-quality-controlled meteorological observations and digital elevation models (DEMs) will drive the model in order to reconstruct LGM glacier extents mapped using field and remote sensing methods for a feasible number of sites having well-established chronologies.