Dr. LeGrande studies climate change using the sophisticated earth system model at the NASA Goddard Institute for Space Studies in New York. Her focus is in identifying mechanisms that force changes in climates from the past to modern satellite studies through future predictions. 

Dr. LeGrande adds:

Actually I use water isotopes and other tracers to study how changes in greenhouse gases, topography, volcanoes, solar input, ozone and more impact climate from the dinosaur times, 55 Million years ago to the last glacial maximum (21000 years ago) to human history (last couple thousand of years) to the present day and into the future.