Tropical cyclones are one of the most damaging and deadly natural disasters and are an energetic element of the climate system. Understanding the character and causes of variations and changes of these cyclones (including potential influences of anthropogenic climate changes) is of profound scientific, economic and human interest. AOS Associate Research Scholar Hiroyuki Murakami is the lead author of a new paper, published November 13 in Nature Climate Change, that addresses recent cyclone behavior. Using the GFDL HiFLOR model, the researchers found that the recent intensity in frequency of intense tropical cyclones in the Arabian Sea was mainly caused by anthropogenic forcing. AOS Faculty Member Gabe Vecchi and GFDL's Seth Underwood are coauthors of the study.