EQUILIBRIUM-LINE ALTITUDE RECONSTRUCTION IN THE SUBTROPICAL ANDES DURING THE LAST GLACIAL MAXIMUM
Despite these climatic conditions that would have supported glaciation during the LGM, there is limited observational evidence. Changes in the equilibrium-line altitude (ELA) can be used to characterize the history of glaciation, and changes in ELA between the LGM and modern in the subtropical Andes can be used to further our understanding of the regional climate during the LGM. Using a glacial mass-balance model in conjunction with GCM output, we calculate the change in ELA between modern and LGM climates in the subtropical Andes. The model uses positive degree-days, the number of days in a year in which the mean annual air temperature is greater than 0°C, to calculate ablation. Ablation is then assumed to be proportional to temperature in order to calculate the change in ELA. Using output from eight GCM simulations, we compare the change in ELA between LGM and modern climates across the different models for the subtropical Andes. These simulations suggest that the changes in climate resulted in a sufficient lowering of ELAs to support glaciation in the subtropical Andes during the LGM.