understanding and constraining uncertainty in
the impacts of climate change


I study where, when, and how climate change and variability will affect people and the natural and managed systems they care about. My research spans a number of projects, including the following:

Hydroclimatic variability and dynamics

There is a high degree of uncertainty in future hydroclimatic changes due to the range of scales required to simulate precipitation and evapotranspiration in models and the uncertainty inherent in a complex climate. My work aims to understand the sources of this uncertainty (both modeled and real-world) using paleo-reconstructions, instrumental observations, and models to improve prediction of the range of hydroclimatic outcomes this coming century. As part of this, I investigate and diagnose the drivers of hydroclimatic change and its consequences for terrestrial hydrology, from low-frequency modes of variability to biogeochemistry of the land surface. Current projects include a focus on the role of vegetation in determining full-column soil moisture in the American Southwest and persistent drought risks in forced versus unforced climates.


Human impacts of climate change

Translating the range of outcomes in physical climate impacts is insufficient to understand what such impacts imply for people and the systems they value. For example, snow is projected to melt in a warmer world, but the human impacts of less snow depends on where and how people use snow to supply water for human consumption. The aim of this work is to incorporate other sciences, both social and natural, to translate physical climate impacts into impacts on humans. Current projects include an examination of the risks of declines in future water availability given human water demand and a bottom-up (agricultural impacts) approach to identifing correlated climate extremes.


Agricultural adaptation decision-making

We know that model-simulated internal variability induced by the atmosphere is sufficient to mask, amplify, or reverse the direction of anthropogenically-forced trends in temperature, circulation, and precipitation at large spatial and temporal scales, complicating adaptation decisions. Characterizing the most likely climate outcome is not sufficient for planning. Rather, quantifying the full extent of outcomes from internal variability under global warming is key to enable adaptation in the face of uncertain climate change threats. Robust decision-making under uncertainty requires the identification of adaptations that produce benefits under the broadest range of outcomes from internal variability. This area of research aims to enable climate risk management and robust decision-making by incorporating these tools into climate science questions. Current projects include identification of the time of emergence and distribution of benefits of agricultural adaptation.



Submitted or in revision

  1. MANKIN, J. S., J. E. Smerdon, B. I. Cook, A. P. Williams, and Richard Seager, The curious case of projected 21st-century drying but greening in the American West, in review, Journal of Climate | Email to request copy

  2. Ault, T., S. St. George, J. E. Smerdon, S. Coats, J. S. Mankin, C. Carrillo, B. I. Cook A robust null hypothesis for the potential causes of megadrought in western North America, in review, Journal of Climate | Email to request copy

  3. Smerdon, J. E. et al., Comparing data and model estimates of hydroclimate variability and change over the Common Era, in review, Climate of the Past | Email to request copy

  4. Cook, B. I., A. P. Williams, J. S. Mankin, , R. Seager, J. E. Smerdon, D. Singh Revisiting the leading drivers of Pacific coastal drought variability in the Contiguous United States, in review, Journal of Climate | Email to request copy

  5. Trugman, A. T., D. Medvigy, J. S. MANKIN, W. R. L. Anderegg, Soil moisture drought as a major driver of carbon cycle uncertainty, in review | Email to request copy

  6. Schultz, K. and J. S. MANKIN, Sources of uncertainty in forecasting the climate-conflict relationship, revising | Email to request copy

  7. Swain, D. L., D. Singh, D. Horton, J. S. Mankin, T. Ballard, N. S. Diffenbaugh, Earth system linkages to anomolous northeastern Pacific atmopsheric ridging, in revision, JGR-A | Email to request copy


  1. Diffenbaugh, N. S., D. Singh, J. S. MANKIN, A. Charland, M. Haugen, D. E. Horton, D. L. Swain, D. E. Touma, M. Tsiang, B. Rajaratnam, 2017: Quantifying the influence of observed global warming on the probability of historically unprecedented extreme climate events, Proceedings of the National Academy of Sciences , 10.1073/pnas.1618082114 | PDF
  2. MANKIN, J. S., D. Viviroli, A. Y. Hoekstra, R. Horton, J. Smerdon, and N. S. Diffenbaugh, 2017: Influence of internal variability on population exposure to hydroclimatic changes, Environmental Research Letters , 10.1088/1748-9326 | PDF
  3. Ault, T. R., J. S. MANKIN, B. I. Cook, J. E. Smerdon, 2016: Relative impacts of mitigation, temperature, and precipitation on 21st Century megadrought risk in the American Southwest, Science Advances , 10.1126/sciadv.1600873 | PDF
  4. Coats, S. and J. S. MANKIN, 2016: The challenge of accurately quantifying future megadrought risk in the American Southwest, Geophysical Research Letters , 10.1002/2016GL070445 | Email to request copy
  5. Singh, S., D. L. Swain, J. S. MANKIN, D. E. Horton, L. Thomas, and N. S. Diffenbaugh, 2016: Recent amplification of the North American winter temperature dipole, Journal of Geophysical Research: Atmospheres , 10.1002/2016JD025116 | PDF
  6. Horton, R., J. S. MANKIN, C. Lesk, E. Coffel, and C. Raymond, 2016: A Review of Recent Advances in Research on Extreme Heat Events, Current Climate Change Reports , 10.1007/s40641-016-0042-x | PDF
  7. MANKIN, J. S., D. Viviroli, D. Singh, A. Y. Hoekstra, and N. S. Diffenbaugh, 2015: The potential for snow to supply human water demand in the present and future, Environmental Research Letters , DOI 10.1088/1748-9326/10/11/114016 | PDF
  8. Moore, F. C., J. S. MANKIN, and A. H. Becker, 2015: Disciplines: Integrating Climate and Social Sciences, Chapter 4 in Climate Cultures: Anthropological Perspectives on Climate Change , Yale University Press | Email to request copy
  9. MANKIN, J. S. and N. S. Diffenbaugh, 2015: Influence of temperature and precipitation variability on near-term snow trends, Climate Dynamics , DOI 10.1007/s00382-014-2357-4 | PDF
  10. Siegfried, T., T. Bernauer, R. Guiennet, S. Sellars, A. W. Robertson, J. S. MANKIN, P. Bauer-Gottwein, 2011: Will Climate Change Exacerbate or Mitigate Water Stress in Central Asia?, Climatic Change , DOI 10.1007/s10584-011-0253-z | PDF
  11. MANKIN, J. S., 2009: Gaming the system: how Afghan opium underpins local power, Journal of International Affairs , Vol. 63, No. 1. | PDF

In preparation (full drafts only)

  1. Schultz, K. & J. S. Mankin, The influence of conflict on temperature, drafted | Email to request copy

  2. MANKIN, J. S., M. Tsiang, B. Rajaratnam, and N. S. Diffenbaugh, A model of Afghan poppy farmer decision-making, drafted | Email to request copy


I am an interdisciplinary climate scientist and an Earth Institute Postdoctoral Fellow at Columbia University, jointly appointed by Lamont-Doherty Earth Observatory and NASA Goddard Institute for Space Studies. My research aims to constrain the uncertainty essential to understanding and responding to climate change’s impacts on people. Working on water and agriculture, I focus on two of the major sources of uncertainty in climate impacts assessments: the chaos of the climate system and the complexity of how people respond to climate stress. I hope my research can help inform the adaptation and risk management decisions people undertake in response to the uncertain threats from climate change. This requires advances in both basic and applied climate science, to include the integration of risk management, economics, and the communication of uncertainty. My previous career was as an intelligence officer working in South Asia and the Middle East. I am from Vermont and I hold degrees from Columbia University (BA, MPA), the London School of Economics (MSc), and Stanford University (PhD).

Present position

Postdoctoral Research Fellow

Lamont-Doherty Earth Observatory & Center for Climate Systems Research at NASA Goddard Institute for Space Studies, Columbia University

Earth Institute Fellow; mentored by Richard Seager, Radley Horton, & Jason Smerdon


PhD, School of Earth, Energy, & Environmental Sciences, Stanford University, Stanford, CA, USA, 2015
Environment & Resources; advised by Noah Diffenbaugh

MPA, SIPA & The Earth Institute, Columbia University, New York, NY, USA, 2010
Environmental Science & Policy

MSc, London School of Economics & Political Science, London, UK, 2008
Global Politics & Development Studies

BA, Columbia University, New York, NY, USA, 2004
Political Science


Ocean and Climate Physics
Lamont-Doherty Earth Observatory
Columbia University
61 Route 9W, P.O. Box 1000
Palisades, NY 10964
Phone: (845) 365-8373
jsmankin [at] ldeo.columbia [dot] edu
Center for Climate Systems Research
NASA Goddard Institute for Space Studies
2880 Broadway
New York, NY 10025
Phone: (212) 678-5549
justin.mankin [at] nasa [dot] gov