When NASA's Orbiting Carbon Observatory, or OCO-2, launches in 2013, Daven Henze will be watching closely. As an assistant professor of mechanical engineering in the department’s air quality group, Henze uses scientific data from orbiting satellites to maintain and improve an "adjoint" model of the Earth's atmosphere, which traces atmospheric chemicals, like ozone and other greenhouse gases, backward to their source.
OCO-2 is one more Earth science satellite that Henze hopes to use in his research. He and his students integrate observational data from instruments aboard satellites with various atmospheric models to closely examine the role that greenhouse gases and particulate matter, known as aerosols, play in air quality and climate change. Using numerical models and inverse modeling techniques, they try to estimate the sources and the fates of various chemical species.
The launch of several new Earth science satellites in the last decade has revolutionized our approach to atmospheric chemistry, Henze says: "They are giving us an unprecedented amount of data, and we now have much greater coverage of the planet."
Models are continuously being improved with the launch of additional instruments and integration of new data, but the question of where pollutants come from is still a challenging one requiring complex mathematical formulas and knowledge of the ways that chemicals change form. The research being conducted by Henze's group is based on techniques borrowed from control and optimization theory, in which the sensitivity of a model's response is calculated with respect to numerous parameters.
Henze, who completed a postdoctoral fellowship at Columbia University's Earth Institute before coming to CU-Boulder, uses a high-performance computing system called Prospero to crunch the numbers and help answer the question of where pollutants originate. The system consists of a bank of 32 computers with 384 core processors, and calculations can sometimes take as much as a day or more.
Henze also is planning to take advantage of the campus’ new Janus Supercomputer, which is being used by faculty and students pursuing research in climatology, oceanography, meteorology, land surface dynamics, genomics, structural biology, microbial ecology, renewable energy applications, turbulence, laser-plasma acceleration, and a variety of additional computational science and engineering applications.