Skip to main content

Office Structure and Staff

William Hohenstein

Wes L. Hanson

Wes Hanson joined OEEP’s Climate Change Program Office as an Agricultural Economist in 2018, where he coordinates efforts across the Department to improve greenhouse gas emission estimates in the agricultural sector, and provides senior leadership with economic and environmental analysis of agricultural greenhouse gas mitigation options and renewable energy systems. Wes also oversees updates to the U.S. Agriculture and Forestry Greenhouse Gas Inventory, and USDA’s Quantifying Greenhouse Gas Fluxes in Agriculture and Forestry: Methods for Entity-Scale Inventory report. Wes is an alumnus of the Presidential Management Fellows program, and a member of the Presidential Management Alumni Association. Before joining USDA, Wes served in the United States Air Force as an Integrated Avionics Systems Instrument and Flight Controls technician on the B-2 Stealth Bomber. Mr. Hanson has an MPP in Environmental Policy from the University of Maryland and a B.A. in Environmental Studies from Linfield University.

Christopher G. Hartley 

Dr. Hartley is responsible for the development of policy, tools, and metrics to facilitate private investment in conservation and the participation of farmers, ranchers and forest landowners in emerging environmental markets. Dr. Hartley recently served on assignment to the Office of the Deputy Undersecretary for Research Education and Economics, first as the Acting Administrator for the Economic Research Service and then as a Senior Advisor to the Mission Area. He previously worked for the Natural Resources Conservation Service in Washington, DC and in California and served with the U.S. Peace Corps as an agricultural extension agent in Senegal, West Africa. He is a Certified Crop Advisor, and a licensed Pest Control Advisor. Dr. Hartley attended the University of California at Davis, Davis, CA and holds a Ph.D. Ecology, emphasis Agroecology, M.Sc. Agronomy, MSc. International Agricultural Development.

Elizabeth Marshall

Stephanie Morris

Dr. Stephanie Morris joined the Office of Energy and Environmental Policy (OEEP) as an Agricultural Project Coordinator in March 2021, where she coordinates climate adaptation efforts across the Department. In this role, she works with USDA Mission Areas to integrate climate adaptation into their planning, programs, and activities to prepare the USDA and its stakeholders to be resilient and successful in a changing climate. Stephanie came to OEEP from USDA’s Office of the Chief Scientist, where she was a AAAS Science & Technology Policy Fellow. Prior to joining USDA, she worked as a research scientist at the Environment Laboratories of the International Atomic Energy Agency and served as a NOAA John A. Knauss Legislative Fellow in the U.S. House of Representatives. Dr. Morris has a B.S. in Chemistry from Sewanee: The University of the South and a Ph.D. in Chemical Oceanography from the Massachusetts Institute of Technology and Woods Hole Oceanographic Institution Joint Program.

Jeff O'Hara

Jeff O’Hara is a Senior Agricultural Economist in the Office of Energy and Environmental Policy. Jeff studies incentives and trends in the implementation of climate-smart practices on U.S. farms and ranches. Prior to joining USDA’s Office of the Chief Economist in 2021, Jeff was an economist at USDA’s Agricultural Marketing Service (2015-2021), the Union of Concerned Scientists (2010-2015), and the Chicago Climate Exchange (2007-2010). Jeff received a PhD in economics from University of California, San Diego (2007) and BS in economics from The George Washington University (2000).

Teresa M. Pickett Wade

Anthony Radich

Tony Radich is an Agricultural Economist with the Office of Energy and Environmental Policy. He focuses on analysis of biofuels markets and the biobased economy. He also reviews all Environmental Protection Agency regulations that pertain to biofuels, including the Renewable Fuel Standard, vehicle fuel economy standards, and liquid fuels specifications. Prior to joining USDA in 2016, Tony worked for 15 years at the U.S. Energy Information Administration, where he covered fuel ethanol and biodiesel markets. He contributed to the Annual Energy Outlook, the Short-Term Energy Outlook, and helped to launch the Biodiesel Production Survey. Tony holds an B.A. in Economics and Business, a BS in Mechanical Engineering, and a PhD in Economics.

Julian Reyes

Dr. Julian Reyes is the National Coordinator for the USDA Climate Hubs program. In this role, he provides connection and cohesion across the regional Hubs, integrates Climate Hub work across USDA agencies, coordinates with other climate networks, and engages with stakeholders. Prior, Dr. Reyes was a AAAS Science and Technology Policy Fellow at the U.S. Department of State in their climate change office. He was also a Climate Hub Fellow with the USDA Southwest Climate Hub/ARS Jornada Experimental Range from 2016 to 2019 where he spearheaded development of the AgRisk Viewer and produced new knowledge on agricultural risk management using spatio-temporal patterns of crop insurance loss. He has broad expertise in hydroclimatology, climate change and impacts in agroecosystems, and eco-hydrologic modeling. Dr. Reyes received his PhD and B.S. in civil engineering both from Washington State University.

Mindy Selman

Mindy Selman is a Senior Analyst with the Office of Energy and Environmental Policy. Her areas of expertise include environmental markets (with a focus on water quality and carbon markets) as well as other market-based mechanisms for promoting conservation, conservation metrics, and farm-scale tools for estimating environmental benefits. Ms. Selman leads the development of the Nutrient Tracking Tool (NTT), a farm-scale tool for estimating nutrient and sediment losses from crop and pasture lands.

Margaret Walsh

Dr. Margaret Walsh is OEEP’s Senior Ecologist, focusing on Climate Assessment, Scientific Analysis, Decision-Support Tool Development, International Science, Food Systems and Security, and Sustainability.

Irene Xiarchos

Irene Margaret Xiarchos is a Senior Economist with the Office of Energy and Environmental Policy. She has a PhD in Natural Resource Economics, and a long career in research and policy, evaluating the intersection of energy with agriculture, the environment, and rural development. She is responsible for the GHG estimates from energy use in agriculture, and explores opportunities for sustainable development with a focus in resource management, infrastructure, value chains, markets and trade.

Kathryn L. Zook

Kate Zook serves as a Senior Program Analyst in the Office of Energy and Environmental Policy. Kate works with USDA leadership to coordinate policy and activities related to climate change mitigation, energy, and environmental markets for the U.S. agriculture sector. Her expertise is in policy analysis related to market-based conservation, agriculture, and climate change. Kate has domestic and international experience in agricultural resource management, working for both academic and nongovernmental organizations. She also has served a variety of public policy roles, including a term at the White House in the Office of Management and Budget. Kate earned undergraduate degrees in Agriculture and Natural Resource Management from the University of Delaware, and a Masters of Environmental Management from the Nicholas School of the Environment at Duke University, focusing on economics and policy.