The American Geophysical Union has awarded Soroosh Sorooshian, UC Irvine Distinguished Professor of civil & environmental engineering, the 2013 Robert E. Horton Medal for his outstanding contributions to hydrology. “I am humbled by this honor,” said Sorooshian, director of UC Irvine’s Center for Hydrometeorology & Remote Sensing. “While this wonderful recognition comes to me, it is a shared honor with all my former and current students and collaborators over the past 30 years of my academic career.” According to the Horton Medal committee, “Professor Sorooshian essentially defined the field of model calibration and has shaped the course of its evolution. … The impact of his work is reflected not only in terms of scientific citations, but also in the use of his ideas and works by the hydrologic research community and operational agencies. … Sorooshian is one of the top few scientific ambassadors in the hydrology community, promoting hydrologic science and new-frontier research programs to the general public and to national and world decision-makers.”