John M. Zobitz   Graduate Student, University of Utah Mathematics Email: zobitz AT math DOT utah DOT edu  LCB 333, (801) 585-1637 Last update: October 2, 2006

Research Interests

 The global carbon cycle is driven by interactions between the ocean and the atmosphere, terrestrial ecosystems and the atmosphere and anthropogenic fossil fuel inputs. My goal is to use mathematics to model carbon cycle processes at multiple spatial and temporal scales, elucidate and resolve measurement-based uncertainty of carbon cycle processes, and from the combination of the first two goals, improve model-based estimates.  The mathematics I utilize include:

• process-based dynamical system modeling
• inverse problem parameter estimation techniques
• statistical modeling
• model-data assimilation techniques.

My dissertation research links measurement and modeling based approaches to terrestrial carbon cycle models and measurements in order to:

1. resolve diurnal patterns of carbon cycle processes from measurements
2. evaluate measurement-based uncertainty in the carbon cycle
3. use a model-data assimilation approach to estimate and interpret parameters for a process-based ecosystem model.
   

A link to an old research page can be found here.

•  J. M. Zobitz (2003), "Pascal Matrices and Differential Equations," Pi Mu Epsilon Journal, 11(8):437-444. Pdf
• Pataki, D. E., D. R. Bowling, J. R. Ehleringer, and J. M. Zobitz (2006), "High resolution atmospheric monitoring of urban carbon dioxide sources," Geophys. Res. Lett., 33, L03813, doi:10.1029/2005GL024822. Pdf. Editor's highlight.
• J. M. Zobitz, J. P. Keener, H. Schnyder, D. R. Bowling (2006), “Sensitivity analysis and quantification of uncertainty for isotopic mixing relationships in carbon cycle research,” 2006. Agricultural and Forest Meteorology, 136:56-75. Pdf.
  

•  "Process Based Belowground Carbon Dioxide Modeling in a Desert Ecosystem," Presented at the Fall Meeting of the American Geophysical Union, December 2003. Pdf (1 MB)
• "Analysis of Linear Regression Techniques to Determine  \delta^{18} O_{R} and \delta^{13} C_{R}: Implications and Applications," Presented at the Biosphere-Atmosphere Stable Isotope Network workshop "Oxygen isotopes as a tracer linking global O2, CO2, and H20 cycles," September 2004. Pdf
•  "Sensitivity Analysis and Quantification of Uncertainty for Isotopic Mixing Relationships in Carbon Cycle Research," American Presented at the Fall Meeting of the American Geophysical Union, December 2004. Pdf 
• "Pattern formations in arid ecosystems: a bifurcations analysis" Math 6740, Fall 2004. Pdf
• "Using mathematical inverse theory to estimate respiratory and photosynthetic fluxes in a heterogeneous conifer canopy" Presented at the Utah-Arizona 2005 Biomathematics Summit, May 13, 2005. Pdf
• "Estimating respiratory and photosynthetic fluxes in a heterogeneous conifer forest," IGERT Project Meeting.May 19, 2005.  Pdf
  

Teaching:

• Fall 2004: Math 1100, Quantitative Analysis
•  Spring 2005: Math 2270, Linear Algebra