Primary tabs


No longer at LDEO: 
Lamont Associate Research Professor, Senior Staff
Lamont-Doherty Earth Observatory
Biology and Paleo Environment
Tree Ring Lab
61 Route 9W - PO Box 1000
(845) 365-8193
(845) 365-8150


I am a multi-disciplinary hydroclimatologist whose research aims to understand the causes and consequences of hydrological extremes such as drought. Much of my research focuses on climatology in its own right, and much of my research also aims to improve understanding of how hydrological extremes affect life on earth. Questions that I find especially interesting involve the effects of human-caused climate change on the hydrological cycle, and how these changes affect ecological systems and humanity through extreme events such as heat waves, wildfires, and flooding. My ultimate goal is to advance scientific knowledge in ways that are relevant to policy makers and future scientific endeavors, and also interesting to the public and other scientists.

List of degrees from highest to lowest:
University of California, Santa Barbara
University of California, Santa Barbara
University of California, Irvine
Honors & Awards: 
2017 Palisades Geophysical Institute Young Scientist Award - Lamont-Doherty Earth Observatory
2016-2018 Fellowship from Columbia University's Center for Climate and Life
2013 Ecological Society of America's Gene E. Likens award for best paper by an early-career scientist in Biogeosciences
2009 Graduate Student Researcher of the Year - UC Santa Barbara Geography

Referenced in the Following News Items:

Featured in the Following Videos:

Selected Publications:

Large contribution from anthropogenic warming to an emerging North American megadrought Williams, Alton P; Cook, Edward R; Smerdon, Jason E; Cook, Benjamin I; Abatzoglou, John T; Bolled, Kasey; Baek, Seung H; Badger, Andrew M; Livneh, Ben Science Volume: 368 Issue: 6488 p.: 314-318 (2020) 10.1126/science.aaz9600
Investigating the causes of increased twentieth-century fall precipitation over the southeastern United States Bishop, Daniel A.; Williams, A. Park; Seager, R.; Fiore, Arlene M.; Cook, Benjamin I.; Mankin, Justin S.; Singh, Deepti; Smerdon, Jason E. Journal of Climate Volume: 32 Issue: 2 p.: 575-590 (2019) 10.1175/JCLI-D-18-0244.1
Observed impacts of anthropogenic climate change on wildfire in California Williams, A. Park; Abatzoglou, John T.; Gershonov, A. Guzman-Moralez, J; Bishop, Daniel A.; Balch, Jennifer K.; Lettenmaier, Dennis P. Earth's Future Volume: 7 Issue: 8 p.: 892-910 (2019) 101029/2019EF001210
Effect of reduced summer cloud shading on evaporative demand and wildfire in coastal southern California Williams, A. Park; Gentine, Pierre; Moritz, Max A.; Roberts, Dar A.; Abatzoglou, John T. Geophysical Research Letters Volume: 45 Issue: 11 p.: 5653-5662 (2018) 10.1029/2018GL077319
The 2016 southeastern US drought: an extreme departure from centennial wetting and cooling Williams, A. Park; Cook, Benjamin I.; Smerdon, Jason E.; Bishop, Daniel A.; Seager, Richard; Mankin, Justin S. Journal of Geophysical Research - Atmospheres Volume: 122 Issue: 20 p.: 10888-10905 (2017) 10.1002/2017JD027523
Recent advances and remaining uncertainties in resolving past and future climate effects on global fire activity Williams, A. Park; Abatzoglou, John T. Current Climate Change Reports Volume: 2 Issue: 1 p.: 1-14 (2016) 10.1007/s40641-016-0031-0
Impact of anthropogenic climate change on wildfire across western US forests Abatzoglou, John T.; Williams, A. Park Proceedings of the National Academy of Sciences USA Volume: 113 Issue: 42 p.: 11770–11775 (2016) 10.1073/pnas.1607171113
Urbanization causes increased cloud-base height and decreased fog in coastal southern California Williams, A. Park; Schwartz, R.; Iacobellis, S.; Seager, R.; Cook, Benjamin I.; Still, Christopher J.; Husak, Gregory; Michaelsen, Joel Geophysical Research Letters Volume: 42 Issue: 5 p.: 1527-1536 (2015) 10.1002/2015GL063266
Contribution of anthropogenic warming to California drought during 2012–2014 Williams, A. Park; Seager, Richard; Abatzoglou, John T.; Cook, Benjamin I.; Smerdon, Jason E.; Cook, Edward R. Geophysical Research Letters Volume: 42 Issue: 16 p.: 6819-6828 (2015) 10.1002/2015GL064924
Temperature as a potent driver of regional forest-drought stress and tree mortality Williams, A. Park; Allen, Craig D.; Macalady, Alison K.; Woodhouse, Connie; Meko, David; Swetnam, Thomas W.; Cook, Edward R.; Griffin, Daniel; Rauscher, Sara A.; Seager, Richard; Dean, J.; Grissino-Mayer Henri D.; Gangodagamage C.; Cai, M., McDowell, N. Nature Climate Change Volume: 3 Issue: 3 p.: 292-297 (2013) 10.1038/nclimate1693