Mark R. Petersen is a research scientist for the US Department of Energy, where he is responsible for climate models that run on high-performance computers. He specializes in designing algorithms for ocean models, which includes code development, model verification and validation, computational performance, and scientific analysis. This work has led to a variety of research topics, including the comparison of models to ground observations and machine learning. Mark enjoys mentoring young scientists, from high school to graduate students, and has mentored a number of high school students who have become finalists at the International Science and Engineering Fair. Mark received a PhD in Applied Mathematics from the University of Colorado at Boulder, and joined Los Alamos National Laboratory in 2005.