Allan Frei


Professor; Undergraduate Geography Advisor; and Deputy Director, Institute for Sustainable Cities at Hunter College


Geography Major Advising Email:
Phone: 212-772-5322
Office: 1005 HN


Allan Frei is a climatologist whose research interests have focused on the potential impact of climate change on hydrology, including snow cover and extreme storms and floods. Recent projects include an investigation of potential impacts of climate change on New York City's water supply in collaboration with the New York City Department of Environmental Protection. Prof. Frei’s main educational interests have been in curriculum development for Environmental Studies and Physical Geography. Prof. Frei formerly served as Chair of the Department of Geography and Environmental Science at Hunter College, and currently serves as the advisor to Geography majors, and as a Deputy Director of the Institute for Sustainable Cities at Hunter College.


Ph.D. 1997 Rutgers University, New Brunswick, NJ, Geography
M.S. 1987 New York University, New York, NY, Applied Science
B.A. 1983 New York University, New York, NY, Computer Science

Research Interests:

Climate variations, snow cover fluctuations, water resources

Teaching Interests:

Weather & climate, earth systems science, quantitative methods, and urban water supply

Current Projects:

  • Evaluate potential impacts of climate change on New York City water supply

Publications: selected publications since 2014

Suriano, Zachary, Daniel J. Leathers, Dorothy K. Hall, Allan Frei, 2019, Contribution of Snowfall from Diverse Synoptic Conditions in the Catskill/Delaware Watershed of New York State, International Journal of Climatology, 10.1002/joc.6043

Mukundan, Rajith, Emmet Owens, Nachiketa Acharya, Allan Frei, Rakesh Gelda, 2019, Modeling streamflow sensitivity to climate change in New York City water supply streams using a stochastic weather generator, Journal of Hydrology: Regional Studies, V21, p. 147-158, DOI: 10.1016/j.ejrh.2019.01.001

Towey, K. L., J. F. Booth, A. Frei, and M. R. Sinclair, 2018: Track and Circulation Analysis of Tropical and Extratropical Cyclones that Cause Strong Precipitation and Streamflow Events in the New York City Watershed. J. Hydrometeor., 19, 1027 - 1042, doi: 10.1175/JHM-D-17-0199.

Dorothy K. Hall, Allan Frei & Nicolo E. DiGirolamo, 2018, On the frequency of lake-effect snowfall in the Catskill Mountains, Physical Geography, DOI: 10.1080/02723646.2018.1440827

Frei, Allan and Petra Kelly-Voicu, 2017, Hurricane Irene and Tropical Storm Lee: how unusual were they in the Catskill Mountains?, Journal of Extreme Events, Vol. 4, No. 2 (2017) 1750009 (31 pages), DOI: 10.1142/S2345737617500099

Hall, Dorothy K., Nicolo E. DiGirolamo, Allan Frei, 2017 Contribution of Lake-Effect Snow to the Catskill Mountains Snowpack, Proceedings of the 74th Eastern Snow Conference, Ottawa, Ontario, Canada, June 2017

Acharya, Nachiketa, Allan Frei, Jie Chen, Leslie DeCristofaro, Emmet Owens, 2017, Evaluating stochastic weather generators for climate change impact studies of New York City’s primary water supply, Journal of Hydrometeorology, V18, p. 879-896, DOI: 10.1175/JHM-D-16-0169.1

Hall, D.K., A. Frei, N.E. DiGirolamo, J. H. Porter and G.A. Riggs, 2016: Snow cover and extreme streamflow events in the Catskill/Delaware watershed, New York, Proceedings of the IAHR, 31 May – 3 June, 2016, Ann Arbor, MI.

Acharya, Nachiketa, Allan Frei, Emmet Owens, 2015, Analysis of Weather Generators: Extreme Events, (extended abstract) in Proceedings of the Fifth International Workshop on Climate Informatics: CI 2015. J. G. Dy, J. Emile-Geay, V. Lakshmanan, Y. Liu (Eds.). September 2015. ISBN: 978-0-9973548-0-5,, (2 pages)

Porter, James, Adao Matonse, Allan Frei, 2015, The New York City Operations Support Tool (OST): Managing water for millions of people in an era of changing climate and extreme hydrological events, Journal of Extreme Events, Vol. 2, No. 2 (2015) 1550008 (23 pages)

Frei, A. and C. Murphy, 2015, Editorial: Introduction to the JOEE Special Issue on Extreme Hydrological Events in River Systems, Journal of Extreme Events, Vol. 2, No. 2 (2015) 1501002 (4 pages)

Frei, A., Kunkel Kenneth E., Matonse Adao, 2015, The Seasonal Nature of Extreme Hydrological Events in the Northeastern United States, Journal of Hydrometeorology, V16, No. 5, p. 2065-2085, doi:10.1175/JHM-D-14-0237.1

Hall, D.K., A. Frei and S. Déry, 2014: (Chapter 3, Snow Extent), in: Remote Sensing of the Cryosphere, M. Tedesco, ed., Wiley – Blackwell (Oxford, UK).