Veerabhadran "Ram" Ramanathan  (born 24 November 1944) is Edward A. Frieman Endowed Presidential Chair in Climate Sustainability  Scripps Institution of Oceanography, University of California, San Diego. He has contributed to many areas of the atmospheric and climate sciences including developments to general circulation models, atmospheric chemistry, and radiative transfer. He has been a part of major projects such as the Indian Ocean Experiment (INDOEX) and the Earth Radiation Budget Experiment (ERBE), and is known for his contributions to the areas of climate physics, Climate Change and atmospheric aerosols research. He is now the Chair of Bending the Curve: Climate Change Solutions education project of University of California. He has received numerous awards, and is a member of the US National Academy of Sciences. He has spoken about the topic of global warming, and written that "the effect of greenhouse gases on global warming is, in my opinion, the most important environmental issue facing the world today."
Due to his close affiliation with Pope Francis, Ramanathan has been described as "The Popes climate scientist". He was influential in the creation of Laudato si, the Pope's encyclical on climate change.