 Complete the following phrase:  Mernild is one of the worlds leading climate scientists in the fields of glaciology and hydrology, specializing in the impacts of climate change in the Arctic and on the cryosphere, especially the ice sheets glacier mass balance and water levels. He has contributed to a number of international scientific reports, including the annual Arctic Report Card from National Oceanic and Atmospheric Administration NOAA and the Melting Snow and Ice: A Call for Action report, which Vice President Al Gore presented at the 