Timothy W Hilton





University of California, Merced

School of Environmental Engineering

P.O. Box 2039

Merced, CA 95344



Ph.D, Pennsylvania State University

M.S., Pennsylvania State University

B.S.E., Princeton University

Current Position: 
Assistant Project Scientist
Previous Position: 
Postdoctoral Fellow, University of New Mexico
Post-Baccalaureate Tech, Los Alamos National Laboratory
Research Interests: 

I seek to understand the terrestrial biological carbon cycle at regional scales using a combination of atmospheric composition observations, ecosystem–atmosphere flux observations, atmospheric and ecosystem models, and data assimilation methods. Considering a group of field observation sites as a collection in space can yield information that is not apparent from considering each site individually, and I am particularly interested in using models to extract such information. Goals of my work include diagnosing the causes and spatial behavior of variations in the terrestrial biological carbon cycle. Broad research interests include modeling of geophysical phenomena and anthropogenic influences on geophysical systems.


Timothy W. Hilton, A. Zumkehr, S. Kulkarni, J. Berry, M. E. Whelan, and J. E. Campbell [2015]. Large variability in ecosystem models explains uncertainty in a critical parameter for quantifying GPP with carbonyl sulphide. Tellus B, 67(0). ISSN 1600-0889. doi:10.3402/tellusb.v67.26329. URL http://www.tellusb.net/index.php/tellusb/article/view/26329.

Whelan, M. E., Hilton, T. W., J. A. Berry, M. Berkelhammer, A. R. Desai, and J. E. Campbell [2015]. Carbonyl sulfide exchange in soils for better estimates of ecosystem carbon uptake. Atmo- spheric Chemistry and Physics Discussions, 15(15):21095–21132. doi:10.5194/acpd-15-21095-2015. URL http://www.atmos-chem-phys-discuss.net/15/21095/2015/.
Campbell, J. E., M. E. Whelan, U. Seibt, S. J. Smith, J. A. Berry, and Hilton, T. W. [2015]. Atmospheric carbonyl sulfide sources from anthropogenic activity: Implications for car- bon cycle constraints. Geophysical Research Letters, 42(8):3004–3010. ISSN 1944-8007. doi: 10.1002/2015GL063445. 2015GL063445, URL http://dx.doi.org/10.1002/2015GL063445.
Hilton, T. W., K. J. Davis, and K. Keller [2014]. Evaluating terrestrial CO2 flux diagnoses and uncertainties from a simple land surface model and its residuals. Biogeosciences, 11(2):217–235. doi:10.5194/bg-11-217-2014. URL http://www.biogeosciences.net/11/217/2014/.
Hilton, T. W., K. J. Davis, K. Keller, and N. M. Urban [2013]. Improving North American terrestrial CO2 flux diagnosis using spatial structure in land surface model residuals. Biogeosciences, 10(7):4607–4625. doi:10.5194/bg-10-4607-2013. URL http://www.biogeosciences.net/10/4607/2013/.
Krofcheck, D. J., J. U. Eitel, L. A. Vierling, U. Schulthess, T. W. Hilton, E. Dettweiler-Robinson, R. Pendleton, and M. E. Litvak [2013]. Detecting mortality induced structural and functional changes in a pion-juniper woodland using Landsat and RapidEye time series. Remote Sensing of Environment, (0):–. ISSN 0034-4257. doi:http://dx.doi.org/10.1016/j.rse.2013.11.009. URL http://www.sciencedirect.com/science/article/pii/S0034425713004203.
Schaefer, K., C. Schwalm, C. Williams, A. Arain, A. Barr, J. Chen, K. Davis, D. Dimitrov, N. Golaz, T.W. Hilton, D. Hollinger, E. Humphreys, B. Poulter, B. Raczka, A. Richardson, A. Sahoo, P. Thornton, R. Vargas, H. Verbeeck, R. Anderson, I. Baker, D. Baldocchi, T. A. Black, P. Bolstad, J. Chen, P. Curtis, A. Desai, M. Dietze, D. Dragoni, L. Flanagan, R. Grant, L. Gu, G. Katul, C. Kucharik, B. Law, S. Liu, E. Lokipitiya, H. Margolis, R. Matamala, H. McCaughey, R. Monson, J. W. Munger, W. Oechel, C. Peng, D. Price, D. Ricciuto, B. Riley, N. Roulet, H. Tian, C. Tonitto, M. Torn, S. Verma, and E. Weng [2012]. A model-data comparison of Gross Primary Productivity. J. Geophys. Res., 117:G03010. doi:10.1029/2012JG001960.
Gibert, F., G. J. Koch, J. Y. Beyon, T.W. Hilton, K. J. Davis, A. Andrews, P. H. Flamant, and U. N. Singh [2011]. Can CO2 turbulent flux be measured by lidar? A preliminary study. Journal of Atmospheric and Oceanic Technology, 28:365–377. doi:10.1175/2010JTECHA1446.1.
Hilton, T.W., R. Najjar, L. Zhong, and M. Li [2008]. Is there a signal of sea-level rise in Chesapeake Bay salinity? J. Geophys. Res., 113:C09002. Doi:10.1029/2007JC004247.
University Graduate Fellow, The Pennsylvania State University, 2003-2004 academic year. Awarded annually to four Penn State Earth and Mineral Sciences College graduate students to recognize outstanding research potential.
Anne C. Wilson Graduate Award, College of Earth and Mineral Sciences, Pennsylvania State University, August 2003. Provides direct financial support of research activities of outstanding students enrolled in the College of Earth and Mineral Sciences.