Ritvik Sahajpal
Asst. Research Professor
Geographical Sciences
University of Maryland-College Park
PhD
[email protected]
(301)832-4118
August 3, 2016
Education
2014
2007
2003
Ph.D. (Geographical Sciences)
M.A. (Geography)
B.E. (Computer Sc. and Engg.)
University of Maryland-College Park
University of Maryland-College Park
Punjab Engineering College, India
Links
GitHub: https://github.com/ritviksahajpal
Website: http://www.terpconnect.umd.edu/~ritvik/
Skills
Programming languages:
Python (Including libraries: pandas, numpy, scipy, matplotlib, pynio, arcpy)
R (Including libraries: dplyr, ggplot2, reshape, rgdal)
C, C++, HTML, Perl, Shell scripting
Techniques: Machine learning, geostatistics, multivariate analysis
Databases: PostgreSQL, MS Access
Ecosystem models: EPIC, ED, SWAT
Development tools: PyCharm, Github, Netbeans, R Studio, Eclipse, Visual Studio
Remote Sensing/GIS: ArcGIS (including ArcPy, spatial analyst, model builder), ENVI
Operating Systems: Windows, Linux, Mac OS X
Research and professional experience
University of Maryland-College Park
Assistant Research Professor
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Developed machine-learning based global crop condition monitor using remote sensing inputs
Produced global crop phenology dataset using Fourier transforms based curve-fitting
Incorporated crop rotation estimates in a global land-use model
University of Wisconsin-Madison
Postdoctoral scholar
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Geographical Sciences
July 2015 – present
Forest and Wildlife Ecology
July 2014 – May 2015
Performed fine spatial scale land-cover change analysis across the U.S. Midwest using Python
Parameterized and calibrated agro-ecosystem model (EPIC) using machine learning approaches in R
Estimated biomass and greenhouse gas fluxes using data driven agro-ecosystem modeling
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University of Maryland-College Park
Affiliate Research Assistant Professor
Geographical Sciences
September 2014 - present
University of Maryland-College Park
Geographical Sciences
Doctoral research assistant
June 2012 – May 2014
 Successfully led major lab initiative to scale terrestrial ecosystem model (Ecosystem Demography or
ED) from globally capable to global
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Visualized impact of coarsening of ED model inputs on model output at different spatial scales
Developed efficient method to reduce ED model run time over one hundred fold
Used ED to derive high spatial resolution biomass and carbon sequestration maps for poplar
plantations in U.S. Midwest
Joint Global Change Research Institute
Terrestrial Processes and Adaptation Group
Doctoral research assistant
January 2010 – May 2012
 Led spatially explicit data analysis for biofuel production for a highly recognized publication in Nature
 Used multivariate and geostatistical methods to determine potential for increasing yields of biofuel
feedstocks in U.S. Midwest
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Produced first national scale maps on prevalence of crop rotations for the U.S.
Designed model to simulate landscape diversity impacts on pest control in U.S. Midwest
Worked as part of team to advance high-resolution spatially explicit modeling of biomass and carbon
fluxes of agricultural systems across the U.S.
University of Maryland-College Park
Geography
Head teaching assistant
September 2008 – December 2009
 Designed introductory and completely online GIS, remote sensing and statistics classes for newly
established Masters in professional studies in GIS program (MPS-GIS)
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Responsible for training incoming teaching assistants in the MPS-GIS program
Taught an undergraduate course on introduction to GIS
Rewarded as distinguished teaching assistant in 2009
University of Maryland-College Park
Geography
Masters research assistant
August 2005 – August 2008
 Designed and operationalized a genetic algorithm for disaster-resilient location-allocation
optimization
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Worked as part of team to quantitatively evaluate inter-city pandemic risks and optimization of
interventions
Quark Media House
Software Engineer, Member-R&D team
August 2003 – September 2004
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Media Lab Asia
Intern
Indian arm of MIT Media Lab
December 2002 - January 2003
Stanford Research Institute (SRI) International
International fellow
Menlo Park, CA
Summer 2001, 2002
Selected peer-reviewed publications (Google Scholar link)
315 citations as of August 3, 2016
2016
Flanagan, S. A., Hurtt, G. C., Fisk, J. P., Sahajpal, R., Hansen, M. C., Dolan, K. A., Sullivan,
J. H., Zhao, M.
Potential Vegetation and Carbon Redistribution in Northern North America from Climate Change
Climate 4, no. 1, 2
2016
Mladenoff, D., Sahajpal, R., Johnson, C.P., Rothstein, D. E.
Recent land cover change to agriculture in the Lake States, USA: Implications for perennial cellulosic
biomass production
PloS one 11, no. 2, e0148566.
2015
Nagol, J., Sexton, J., Anand, A., Sahajpal, R.
Extraction of end-member phenology by spectral unmixing.
PloS one. In review.
2015
Zhang, X., Izaurralde, R. C., Manowitz, D. H., Sahajpal, R., West, T. O., Thomson, A. M.,
Xu, M., Zhao, K., LeDuc, S. D., Williams, J. R.
Regional scale cropland carbon budgets: Evaluating a geospatial agricultural modeling system using inventory
data.
Environmental Modelling and Software, 63, 199-216.
2014
Porter, C. H., Villalobos, C., Holzworth, D., Nelson, R., White, J. W., Athanasiadis, I. N.,
Janssen, S., Ripoche, D., Cufi, J., Raes, D., Zhang, M., Knapen, R., Sahajpal, R., Boote, K.,
Jones, J. W.
Harmonization and translation of crop modeling data to ensure interoperability.
Environmental Modeling and Software, 62, 495-508.
2014
Sahajpal, R., Zhang, X., Izaurralde, R. C., Gelfand, I., Hurtt, G. C.
Identifying representative crop rotation patterns and grassland loss in the U.S. western corn- belt.
Computers and Electronics in Agriculture, 108, 173-182.
2014
Zhang, X., Sahajpal, R., Manowitz, D. H., Zhao, K., LeDuc, S. D.,et al.
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Multi-scale geospatial agroecosystem modeling: A case study on the influence of soil data resolution on carbon
budget estimates.
Science of the Total Environment, 479, 138-150.
2013
Gelfand, I., Sahajpal, R., Zhang, X., Izaurralde, R. C., Gross, K. L., Robertson, G. P.
Sustainable bioenergy production from marginal lands in the U.S. Midwest.
Nature, 493(7433), 514-517.
Highlights:
NPR, NSF, F1000, Scientific American
BSOS, PNNL, MSU, Future Science, UMD
2013
Zhang, X., Beeson, P., Link, R., Manowitz, D., Izaurralde, R. C., Sadeghi, A., Thomson,
A.M., Sahajpal, R., Srinivasan, R., Arnold, J.
Efficient multi-objective calibration of a computationally intensive hydrologic model with parallel computing
software in Python.
Environmental Modelling & Software, 46, 208-218.
2012
Izaurralde R. C., Zhang, X., Sahajpal, R., Manowitz, D. H.
National geo-database for biofuel simulations and regional analysis of biorefinery siting based on cellulosic
feedstock grown on marginal lands.
PNNL-21283, Pacific Northwest National Laboratory, Richland, WA.
2012
Izaurralde R. C., Zhang, X., Sahajpal, R., Manowitz, D. H.
National geo-database for biofuel simulations and regional analysis.
PNNL-21284, Pacific Northwest National Laboratory, Richland, WA.
2008
Chen, Y., Cornick, N., Hall, A.O., Sahajpal, R., Silberholz, J., Yahav, I., Golden, B. L.
Comparison of heuristics for solving the gmlst problem.
In Telecommunications Modeling, Policy, and Technology, pp. 191-217. Springer US.
Peer-reviewing activity
Geoforum
BioEnergy Research
GCB Bioenergy
Sensors
Global Environmental Change
Journal of Industrial Ecology
Remote Sensing
Global Biogeochemical Cycles
Agronomy Journal (3)
Intl Journal of Remote Sensing
Grant Activity
Submitted
2016 Co-I
NASA
Earth observations and environmental modeling to support
decisions on biomass production development in Argentina –
impact on water use efficiency, ecosystem diversity and
sustainability.
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Selected
2016 Co-I
NASA
Cropland Carbon Monitoring System (CCMS): A SatelliteBased System to Estimate Carbon Fluxes on U.S. Croplands.
Not selected
2014 Co-I
NASA
UAV-based approach for forest biomass and carbon
monitoring for REDD+ projects and OCO-2 accuracy
assessment.
2014
NASA
The changing landscape of human-environment interactions
in the western himalayan region.
Co-I
Awards and Recognition
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Goldhaber Travel Grant, 2013
Distinguished Teaching Assistant, Department of Geography, 2009
Silver Medal, Punjab Engineering College, 2003
International Fellow, Stanford Research Institute International, 2001, 2002
Interviewed by BBC for developing Hindi chatbot technology
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