A.J. Purdy

Sr. Research Scientist
California State University at Monterey Bay

Google Scholar | ResearchGate

I am interested in the water cycle including its relation to human activity, the environment, and the earth system. My research uses satellite observations and models to track how water resources and water cycling is changing around the world. I am particularly interested in developing tools and applications to support stakeholders manage freshwater resources under a changing climate.

Publications


Resume


Conference Presentations


  • Felton,A ... Purdy, A.J., et al., Global estimates of the storage and transit time of water through vegetation AGU Fall 2021
  • Halverson, G., ... Purdy, A.J., et al., Improvements to ECOSTRESS Algorithms and Products in Collection 2 AGU Fall 2021
  • Khanna, M., Halverson, G., Purdy, A.J., et al., An overview of NASA JPL’s remotely sensed evapotranspiration data Poster Presentation AGU Fall 2019
  • Fisher, J.B., Lee, B., Purdy, A.J. et al., First evapotranspiration results from NASA’s ECOSTRESS mission Oral Presentation AGU Fall 2019
  • A.J. Purdy, J. Fisher, J. Kawata, G. Om, M. Reynolds, Z.M. Ali, J. Babikian, C. Roman, M. Sikka., Designing Drought Indicators Oral Presentation AGU Fall 2018
  • J.S. Famiglietti, P.W. Liu, A. McEvoy, D.N. Wiese, J.T. Reager, A.J. Purdy, M. Rodell, C.H. David., Food Grows where Groundwater Flows: California Grapples with Chronic Water Scarcity. Oral Presentation AGU Fall 2018
  • Purdy, A.J., Fisher, J., Goulden, M.L., Randerson, J.S., Famiglietti, J.S., Water vs. Carbon: An evaluation of SMAP soil moisture, evapotranspiration, & OCO-2 solar induced fluorescence to characterize global plant stress. Poster Presentation AGU Fall 2017
  • Purdy, A.J., Fisher, J., Famiglietti, J.S., Potential for SMAP soil moisture observations to improve remote sensing of evapotranspiration algorithms. Oral Presentation AGU Fall 2016
  • Purdy, A.J., Fisher, J., Famiglietti, J.S., Ground Heat Flux: What’s the best approach. Oral Presentation AGU Fall 2015
  • Castle, S., Reager, J.T., Thomas, B.F.,Purdy, A.J., Lo, M. H., Rodell, M., Famiglietti, J.S., Assessing the impacts of water management on evapotranspiration in the Colorado River Basin. H34D-06 AGU Fall 2014
  • Purdy, A.J., Famiglietti, J.S. Remote sensing and modeling evapotranspiration: A high-resolution multi-method comparison at point and basin scales in California. Oral Presentation AGU Fall 2013
  • Melton, F.S. Lund, C., Johnson, L., Michaelis, A., Pierce, L., Guzman, A., Hiat, S., Purdy, A.J., Rosevelt, C., Brandt, W., Votava, P., Nemani, R., Satellite Mapping of Agricultural Water Requirements in California with the Terrestrial Observation and Prediction System. H21H-1272 AGU Fall 2012
  • Purdy, A.J., Lund, C.P., Pierce, L., Melton, F.S., Guzman, A., Harlen, I., Holloway, R., Johnson, L., Lee, C., Nemani, R.. Applications of wireless sensor networks, soil water balance modeling, and satellite data for crop evapotranspiration monitoring and irrigation management support. H21F-120: Poster AGU Fall 2011
  • Melton, F., Johnson, L., Lund, C., Michaelis, A., Pierce, L., Guzman, A., Hiat, S., Purdy, A.J., Lee, C., Rosevelt, C., Fletcher, N., Votava, P., Milesi, C., Hashimoto, H., Wang, W., Scheffner, E.J., Nemani, R., Satellite Monitoring and Management Support in California with the Terrestrial Observation and Prediction System H21F-1227 AGU Fall 2011

White Papers


Data


    Global ET data from Purdy et al., 2018
  • 36 km monthly data from 2015-2017
  • 9 km monthly data from 2015-2017
    • ET data use policy: All studies should cite:
  • Purdy et al., 2018 SMAP soil moisture improves global evapotranspiration.
  • Fisher et al., 2008 Global estimates of the land–atmosphere water flux based on monthly AVHRR and ISLSCP-II data, validated at 16 FLUXNET sites
  • If appropriate, please feel free to invite me as a collaborator. Please provide at least two weeks notice to provide substantive contributions to analysis and manuscript to merit coauthorship. Reach out if you need data at a different cadence and/or generated with a different forcing dataset.

    Teaching


    Prior to CSUMB, I taught, created, and developed a number of graduate and undergraduate geosptial technology and GIS classes. Below you can find a list of courses by year.

    Spring 2022
  • ENVM 681 GIS & Watershed Systems
  • ENVS 376 GIS 2: Intermediate GIS and geospatial programming
  • Fall 2021
  • ENVM 677 Introduction to Google Earth Engine
  • ENVM 673 Accelerated introduction to GIS
  • ENVS 375 GIS 1: Introduction to geospatial technology & GIS
  • Spring 2021
  • ENGY 680 Mapping Sustainable Energy
  • ENVM 680 Remote Sensing with GIS
  • ENVM 674 Accelerated intermediate to GIS
  • ENVS 376 GIS 2: Intermediate GIS and geospatial programming
  • Fall 2020
  • ENVM 680 GIS & Watershed Systems
  • ENVM 673 Accelerated introduction to GIS
  • ENVS 375 GIS 1: Introduction to geospatial technology & GIS
  • Spring 2020
  • ENVM 680 Remote Sensing with GIS
  • ENVM 673 Accelerated introduction to GIS
  • ENVS 390 GIS 2: Intermediate GIS and web-mapping
  • Fall 2019
  • ENVM 673 Accelerated introduction to GIS
  • ENVS 375 GIS 1: Introduction to geospatial technology & GIS
  • About Me


    I am currently a senior research scientist at California State University at Monterey Bay (CSUMB). I am optimistic about the power of science to impart positive change in one's local community and the world. At CSUMB I look forward to developing new applications of satellite data to support water managers, agricultural producers, and land managers in California.

    Prior to CSUMB, I served as an assistant professor at University of San Francisco (2019-2022) and a postdoctoral fellow at NASA's Jet Propulsion Laboratory (2018-2019). My research experience includes using data from multiple NASA satellite missions (Landsat, MODIS, SMAP, GRACE, and ECOSTRESS) to advance science related hydrology and water resources.

    I hold a PhD in Earth System Science from UC Irvine and a MS in Watershed Science and Policy from CSUMB. My PhD dissertation focused on the advancement and applications of satellite-derived evapotranspiration algorithms.

    Outside of the office, I enjoy spending my time surfing, camping, and adventuring with my family.

    Contact


    My contact information is listed at the top my resume. Please contact me if you want to join on-going research projects, see an oportunity to colaborate, or just want to chat science, education, or adventures.