Career
He is a Professor of Meteorology at Texas Agricultural and Mechanical University, and the Texas State Climatologist, holding both appointments since 2000. His research group uses a combination of observational and computational techniques to study the characteristics, dynamics, and forecasting of certain weather phenomena. Much of his recent work has involved air pollution meteorology.
He writes a popular online column on climate science for the Houston Chronicle.
He wrote, My goal is to be completely honest, fair, and intelligent in my public outreach, thereby guaranteeing that there’s at least one of us. (But, to be fair, fairness is in the eye of the beholder) On December 22, 2009, Nielsen-Gammon wrote a detailed analysis of the erroneous projected date of melting of Himalayan glaciers in the Working Group II section of the IPCC Fourth Assessment Report which said that "the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate." This had already been controversial in India, and the error had been found by J. Graham Cogley, a glaciologist in the Department of Geography at Trent University, Ontario.
The story had been covered by British Broadcasting Corporation News but had not at that time gained wider publicity. Nielsen-Gammon"s article identified and documented further details of the sources of the error.
Nielsen-Gammon earned an South.B. (Earth and Planetary Sciences), South.M. (Meteorology), and Doctor of Philosophy (Meteorology), all from Massachusetts Institute of Technology. Both Kerry Emanuel and Richard South. Lindzen were on his Doctor of Philosophy committee.