Gregory M. Flato

Image Gregory Flato
Senior Research Scientist - Conducts research related to Environment Canada's global and regional earth system models, and their application to historical climate simulation, seasonal to interannual climate prediction, and long-term climate projection

Current research and/or projects

Development, application and evaluation of global and regional climate models.

Professional activities / interests

co-Chair, World Climate Research Programme (WCRP) Working Group on Coupled Modelling

vice-Chair, Working Group I, Intergovernmental Panel on Climate Change (IPCC)

Coordinating Lead Author of Chapter 9 "Evaluation of Clilmate Models" in the Working Group 1 contribution to the Intergovernmental Panel on Climate Change 5th Assessment Report, 2013.

Lead Author of Chapter 4 "Changes in Snow, Ice and Frozen Ground" in the Working Group 1 contribution to the Intergovernmental Panel on Climate Change 4th Assessment Report, 2007.

Education and awards

B.Sc., M.Sc. Engineering, University of Alberta;

Ph.D. Dartmouth College (USA)

Canadian Meteorological and Oceanographic Society National Tour Speaker (1999)

American Geophysical Union Editors' Citation for Excellence in Reviewing, JGR-Oceans (1995 and 2000)

International experience and/or work

Elected member of the IPCC Bureau.

Lead Author and contributor to Arctic Council's Arctic Monitoring and Assessment Programme (AMAP) reports

Former member of the World Climate Research Programme (WCRP) Joint Scientific Committee.

Former chair of the WCRP Climate and Cryosphere core project.

Key publications

Meehl, G.A., C.A. Senior, V. Eyring, G. Flato, J-F Lamarque, R.J. Stouffer, K.E. Taylor, and M. Schlund, 2020: Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models. Science Advances, 6:eaba1981.

Eyring, V., P.M. Cox, G.M. Flato, P.J. Gleckler, G. Abramowitz, P. Caldwell, W.D. Collins, B.K. Gier, A.D. Hall, F.M. Hoffman, G.C. Hurtt, A. Jahn, C.D. Jones, S.A. Klein, J.P. Krasting, L. Kwiatkowski, R. Lorenz, E. Maloney, G.A. Meehl, A.G. Pendergrass, R. Pincus, A.C. Ruane, J.L. Russell, B.M. Sanderson, B.D. Santer, S.C. Sherwood, I.R. Simpson, R.J. Stouffer, and M.S. Williamson, 2019: Taking climate model evaluation to the next level. Nature Clim. Change, 9, no. 2, 102-110, doi:10.1038/s41558-018-0355-y.

Bush, E. and Flato, G. (2019): About this report; Chapter 1 in Canada’s Changing Climate Report, (ed.) E. Bush and D.S. Lemmen; Government of Canada, Ottawa, Ontario, p. 7-23.

Flato, G., Gillett, N., Arora, V., Cannon, A. and Anstey, J. (2019): Modelling Future Climate Change; Chapter 3 in Canada’s Changing Climate Report, (ed.) E. Bush and D.S. Lemmen; Government of Canada, Ottawa, Ontario, p. 74-111.

Zhang, X., Flato, G., Kirchmeier-Young, M., Vincent, L., Wan, H., Wang, X., Rong, R., Fyfe, J., Li, G., Kharin, V.V. (2019): Changes in Temperature and Precipitation Across Canada; Chapter 4 in Bush, E. and Lemmen, D.S. (Eds.) Canada’s Changing Climate Report. Government of Canada, Ottawa, Ontario, pp 112-193.

Cohen, S., Bush, E., Zhang, X., Gillett, N., Bonsal, B., Derksen, C., Flato, G., Greenan, B., Watson, E. (2019): Synthesis of Findings for Canada’s Regions; Chapter 8 in Canada’s Changing Climate Report, (ed.) E. Bush and D.S. Lemmen; Government of Canada, Ottawa, Ontario, p. 424-443.

Kharin, V. V., Flato, G. M., Zhang, X., Gillett, N. P., Zwiers, F., & Anderson, K. J. (2018). Risks from climate extremes change differently from 1.5°C to 2.0°C depending on rarity. Earth’s Future, 6.

Kushner, P. J., Mudryk, L. R., Merryfield, W., Ambadan, J. T., Berg, A., Bichet, A., Brown, R., Derksen, C. P., Déry, S. J., Dirkson, A., Flato, G., Fletcher, C. G., Fyfe, J. C., Gillett, N., Haas, C., Howell, S., Laliberté, F., McCusker, K., Sigmond, M., Sospreda-Alfonso, R., Tandon, N. F., Thackeray, C., Tremblay, B., and Zwiers, F. W., 2018: Assessment of Snow, Sea Ice, and Related Climate Processes in Canada's Earth-System Model and Climate Prediction System, The Cryosphere 12, 1137–1156,


Flato, G., M. Ananicheva, E. Antonov, D. Atkinson, R. Brown, L. Hamilton, L. Harwood, G. Jia, V. Kattsov, K. Kivva, M. Muir, P. Outridge, J. Overland, R. Rong, N. Steiner, G. Stern, J. Walsh, X. Wang. 2017: Chapter 4. Regional drivers and projections of regional change, In: Adaptation Actions for a Changing Arctic: Perspectives from the Bering-Chukchi-Beaufort Region. pp. [89-124]. Arctic Monitoring and Assessment Programme (AMAP), Oslo, Norway.

Kushner, P. J., Mudryk, L. R., Merryfield, W., Ambadan, J. T., Berg, A., Bichet, A., Brown, R., Derksen, C. P., Déry, S. J., Dirkson, A., Flato, G., Fletcher, C. G., Fyfe, J. C., Gillett, N., Haas, C., Howell, S., Laliberté, F., McCusker, K., Sigmond, M., Sospreda-Alfonso, R., Tandon, N. F., Thackeray, C., Tremblay, B., and Zwiers, F. W.: Assessment of Snow, Sea Ice, and Related Climate Processes in Canada's Earth-System Model and Climate Prediction System, The Cryosphere Discuss.,, in review, 2017.

Zadra, A., K. Williams, A. Frassoni, M. Rixen, A. Adames, J. Berner, F. Bouyssel, B. Casati, H. Christensen, M. Ek, G. Flato, Y. Huang, F. Judt, H. Lin, E. Maloney, W. Merryfield, A. van Niekerk, T. Rackow, K. Saito, N. Wedi, and P. Yadav, 2017: Systematic  Errors  in  Weather  and  Climate  Models:  Nature,  Origins,  and  Way  Forward. Bull. Amer. Meteor. Soc. doi:10.1175/BAMS-D-17-0287.1, in press.

Lemieux, J.-F., S. Bouillon, F. Dupont, G. Flato, M. Losch, P. Rampal, L.-B. Tremblay, M. Vancoppenolle, and T. Williams, 2017. Sea Ice Physics and Modelling, Chap. 2 in Sea Ice Analysis and Forecasting, T. Carrieres, M. Buehner, J.-F. Lemieux and L.T. Pedersen (eds.), Cambridge University Press, DOI: 10.1017/9781108277600.

B.D. Santer, J.C. Fyfe, G. Pallotta, G.M. Flato,      G.A. Meehl, M.H. England,  E. Hawkins, M.E. Mann,J.F. Painter, C. Bonfils, I. Cvijanovic,            C. Mears, F.J. Wentz, S. Po-Chedley, Q. Fu, and C.-Z. Zou, 2017. Causes of differences in model and satellite tropospheric warming rates. Nature Geoscience  10,  478–485,   doi:10.1038/ngeo2973

Fyfe, J.C., C. Derksen, L. Mudryk, G.M. Flato, B.D. Santer, N.C. Swart, N.P. Molotch, X. Zhang, H. Wan, V.K. Arora, J. Scinocca, and Y. Jiao, 2017. Large near-term projected snowpack loss over the western United States. Nature Communications, DOI: 10.1038/ncomms14996

Gagne, M.-E., J.C. Fyfe, N.P. Gillett, I.V. Polyakov, and G.M. Flato, 2017. Aerosol-driven increas in Arctic sea ice over the middle of the 20th Century. Geophys. Res. Lett., 44,  doi:10.1002/2016GL071941.

Sigmond, M., M.C. Reader, G.M. Flato, W.J. Merryfield, and A. Tivey, 2016. Skillful seasonal forecasts of Arctic sea ice retreat and advance dates in a dynamical forecast system, Geophys. Res. Lett., 43, DOI: 10.1002/2016GL071396

Lemieux, J.-F., F. Dupont, P. Blain, F. Roy, G. C. Smith, and G. M. Flato (2016), Improving the simulation of landfast ice by combining tensile strength and a parameterization for grounded ridges, J. Geophys. Res. Oceans, 121, doi:10.1002/2016JC012006.

Fyfe, J.C., Meehl, G.A., England, M.H., Mann, M.E., Santer, B.D., Flato, G.M., Hawkins, E., Gillett, N.P., Xie, S.-P., Kosaka, Y., Swart, N.C., 2016. Making sense of the early-2000s global warming slowdown. Nature Climate Change, 6, March 2016, 224-228.

Scinocca, J.F., V.V. Kharin, Y. Jiao, M.W. Qian, M. Lazare, L. Solheim, G.M. Flato, S. Biner, M. Desgagne, and B. Dugas, 2016: Coordinated Global and Regional Climate Modelling. J. Climate, DOI: 10.1175/JCLI-D-15-0161.1

Asrar, G., Bony, S., Boucher, O., Busalacchi, A., Cazenave, A., Dowell, M., Flato, G., et al., 2015:Climate Symposium 2014 – Findings and Recommendations. Bull. Am. Met. Soc., September, 2015, doi:10.1175/BAMS-D-15-0003.1.

Flato, G.M, J. Marotzke, et al., 2013: Chapter 9 – Evaluation of Climate Models in Climate Change 2013 : The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. [Stocker et al., (eds.)]. Cambridge University Press, 1535pp.

Fyfe, J.C., K. von Salzen, N.P. Gillett, V.K. Arora, G.M. Flato, J.R. McConnell, 2013: One hundred years of Arctic surface temperature variation due to anthropogenic influece. Scientific Reports, 3:2645, doi: 10.1038/srep02645.

Merryfield, W., W. Lee, G. Boer, V. Kharin, J. Scinocca, G. Flato, R. Ajayamohan, J. Fyfe, Y. Tang, and S. Polavarapu, 2013: The Canadian Seasonal to Interannual Prediction System. Part I: Models and Initialization. Mon. Wea. Rev. doi:10.1175/MWR-D-12-00216.1

Sigmond, M., J.C. Fyfe, G.M. Flato, V.V. Kharin, W.J. Merryfield, 2013, Seasonal forecast skill of Arctic sea ice area in a dynamical forecast system. Geophysical Research Letters, doi: 10.1002/grl.50129

Godlovitch, D., A. Monahan and G. Flato, 2012: An idealized stochastic model of sea ice thickness dynamics. Cold Regions Science and Technology, 78:14-30.

Gillett, N.P., Arora, V.K., Flato, G.M., Scinocca, J.F., von Salzen, K., 2012: Improved contstraints on 21st- century warming derived using 160 years of temperature observations. Geophys. Res. Lett., 39, doi:1-.1029/2011GL050226.

Flato, G.M., 2011: Earth System Models: An Overview. Wiley Interdisciplinary Reviews, Climate Change. doi: 10.1002/wcc.148 .

Arora, V.K., Scinocca, J.F., Boer, G.J., Christian, J.R., Denman, K.L., Flato, G.M., Kharin, V.V., Lee, W.G., Merryfield, W.J., 2011, Carbon emissions required to satisfy future representative concentration pathways of greenhouse gases. Geophys. Res. Lett., 38, LO5805, doi:10.1029/2010GL046270.

Yang, X-Y, J.C. Fyfe and G.M. Flato, 2010: The role of poleward energy transport in Arctic temperature evolution. Geophys. Res. Lett., in press.

Merryfield, W.J., W.-S. Lee, G.J. Boer, V.V. Kharin, B. Pal, J.F. Scinocca, and G.M. Flato, 2010: The first coupled historical forecasting project (CHFP1), Atmosphere-Ocean, in press.

Christian, J.R., V.K. Arora, G.J. Boer, C.L. Curry, K. Zahariev, K.L. Denman, G.M. Flato, W.G. Lee, W.J. Merryfield, N.T. Roulet and J.F. Scinocca, 2010: The global carbon cycle in the Canadian Earth System Model (CanESM1): Preindustrial control simulation, J. Geophys. Res., in press.

Arora, V.K., G.J. Boer, J.R. Christian, C.L. Curry, K.L. Denman, K. Zahariev, G.M. Flato, J.F. Scinocca, W.J. Merryfield, W.G. Lee, 2009: The effect of terrestrial photosynthesis down-regulation on the 20th century carbon budget simulated with the CCCma Earth System Model, J. Climate, 22: 6066-6088.

Sou, T. and G.M. Flato, 2009: Sea ice in the Canadian Arctic Archipelago: Modelling the past (1950-2004) and the future (2041-2060). J. Climate, 22: 2181-2198.

Saenko, O.A., A.J. Weaver, D.Y. Robitaille, and G.M. Flato, 2007: Warming of the subpolar Atlantic triggered by freshwater discharge at the continental boundary. Geophys. Res. Lett., 34, doi:10.1029/2007GL030674 .

Lemke, P., J. Ren, R. Alley, I. Allison, J. Carrasco, G. Flato, Y. Fuji, G. Kaser, P. Mote, R. Thomas, and T. Zhang, 2007: Observations: Changes in Snow, Ice and Frozen Ground, Chapter 4 in IPCC 2007: Climate Change 2007- The Physical Science Basis, Cambridge U. Press.

Dumas, J.A. , H. Melling, G.M. Flato, 2007: Late-summer pack ice in the Canadian Archipelago: Thickness observations from a ship in transit, Atmosphere-Ocean, 45(1): 57-70.

Dumas, J.A., G.M. Flato, and R.D. Brown, 2006: Future Projections of Landfast Ice Thickness and Duration in the Canadian Arctic, J. Climate, 19: 5175-5189

Stouffer, R.J., J. Yin, J. M. Gregory, K. W. Dixon, M. J. Spelman, W. Hurlin, A. J. Weaver, M. Eby, G. M. Flato, H. Hasumi, A. Hu, J. Jungclause, I. V. Kamenkovich, A. Levermann, M. Montoya, S. Murakami, S. Nawrath, A. Oka, W. R. Peltier, D. Y. Robitaille, A. Sokolov, G. Vettoretti, N. Weber, 2006: Investigating the Causes of the Response of the Thermohaline Circulation to Past and Future Climate Changes, J. Climate, 19(8): 1365–1387.

Flato, G.M. and CMIP contributors, 2004: Sea-ice climate and sensitivity as simulated by global climate models, Climate Dynamics, 23: 229-241.

Boer, G.J., B. Yu, S.-J. Kim and G.M. Flato, 2004: Is there observational support for an El Niño-like pattern of future global warming? Geophys. Res. Lett. 31, L06201, doi:10.1029/2003GL018722.

Duguay, C.R., G.M. Flato, M.O. Jeffries, P. Ménard, K. Morris, and W.R. Rouse, 2003: Ice cover variability on shallow lakes at high latitudes: model simulations and observations. Hydrological Processes, 17(17): 3465-3483.

Dumas, J.A., G.M. Flato and A.J. Weaver, 2003: The impact of varying atmospheric forcing on the thickness of Arctic multi-year sea ice, Geophys. Res. Lett., 30(18), 1918, doi:10.1029/2003GL017433.

Flato, G.M., 2003: Sea Ice Modelling. Chapter 9 in Mass Balance of the Cryosphere: Observations and Modelling of Contemporary and Future Changes, eds. J. Bamber and A. Payne, Cambridge University Press, pg. 367-389.

Ménard P., C.R. Duguay, F.C. Pivot, G.M. Flato, and W.R. Rouse, 2003. Sensitivity of Great Slave Lake ice cover to climate variability and climatic change. Proceedings of the 16th International Symposium on Ice, Dunedin, New Zealand, 2-6 December 2002, Vol. 3, pp. 57-63.

Kim, S.-J., G.M. Flato, G.J. Boer, 2003: A coupled climate model simulation of the Last Glacial Maximum, Part 2: Approach to equilibrium. Climate Dynamics, 20:635-661.

Ménard, P., Duguay, C.R., G.M. Flato, W.R. Rouse, 2002: Simulation of ice phenology on Great Slave Lake, Northwest Territories, Canada. Hydrological Processes, 16:3691-3706.

Kim, S.-J., G.M. Flato, G.J. Boer and N.A. McFarlane, 2002: A coupled climate model simulation of the Last Glacial Maximum, Part 1: Transient multi-decadal response. Climate Dynamics, 19:515-537.

Saenko, O.A., G.M. Flato and A.J. Weaver, 2002: Improved representation of sea- ice processes in climate models. Atmosphere-Ocean, 40(1):21-43.

Bitz, C.M., J.C. Fyfe, and G.M. Flato, 2002: Sea ice response to wind forcing from AMIP models. J. Climate, 15:522-536.

Gregory, J.M., J.A. Church, G.J. Boer, K.W. Dixon, G.M. Flato and 4 others, 2002: Comparison of results from several AOGCMs for global and regional sea-level change 1900-2100. Climate Dynamics, 18:225-240.

Davey, M.K., M. Huddleston, K.R. Sperber, P. Braconnot, F. Bryan, D. Chen, R.A. Colman, C. Cooper, U. Cubasch, P. Delecluse, D. DeWitt, L. Fairhead,G. Flato and 24 others, 2002: STOIC: A study of coupled model climatology and variability in tropical ocean regions. Climate Dynamics, 18:403-420.

Latif, M., K. Sperber, J. Arblaster, P. Braconnot, D. Chen, A. Colman, U. Cubasch, C. Cooper, P. Delecluse, D. Dewitt, L. Fairhead, G. Flato, and 22 others, 2002: ENSIP: The El Nino simulation intercomparison project. Climate Dynamics, 18:255-276.

Flato, G.M. and G.J. Boer, 2001: Warming asymmetry in climate change simulations. Geophys. Res. Lett., 28:195-198.

Weaver, R.L.S., K. Steffen, J. Heinrichs, J. Maslanik, and G.M. Flato. 2000: Data assimilation in sea ice monitoring. Annals of Glaciology, 31:327-332.

Schramm, J.L. G.M. Flato and J.C. Curry. 2000: Towards the modelling of enhanced basal melting in ridge keels. J. Geophys. Res., 105(C6):14,081-14,092.

Goyette, S., N.A. McFarlane, and G.M. Flato. 2000: Application of the Canadian Regional Climate Model to the Laurentian Great Lakes region: Implementation of a lake model. Atmosphere-Ocean, 38:481-503.

Covey, C., A. Abe-Ouchi, G.J. Boer, B.A. Boville, U. Cubasch, L. Fairhead, G.M. Flato, plus 16 others. 2000: The seasonal cycle in coupled ocean-atmosphere general circulation models. Climate Dynamics, 16:775-787.

Flato, G.M., G.J. Boer, W.G. Lee, N.A. McFarlane, D. Ramsden, M.C. Reader, and A.J. Weaver. 2000: The Canadian Centre for Climate Modeling and Analysis Global Coupled Model and its Climate. Climate Dynamics, 16:451-467.

Boer, G.J., G.M. Flato, M.C. Reader, and D. Ramsden. 2000: A transient climate change simulation with greenhouse gas and aerosol forcing: experimental design and comparison with the intrumental record from the 20th century. Climate Dynamics, 16:405-425.

Boer, G.J., G.M. Flato, and D. Ramsden. 2000: A transient climate change simulation with greenhouse gas and aerosol forcing: projected climate change in the 21st century. Climate Dynamics, 16:427-450.

Kreyscher, M., M. Harder, P. Lemke and G.M. Flato. 2000: Results of the Sea Ice Model Intercomparison Project: Evaluatoin of sea-ice rheology schemes for use in climate simulations. J. Geophys. Res., 105, (C5), 11299 - 11320.

Monahan, A.H., J.C. Fyfe and G.M. Flato. 2000: A regime view of northern hemisphere atmospheric variability and change under global warming. Geophys. Res. Lett. 27, 1139-1142.

Steele, M. and G.M. Flato. 2000: Growth, Melt, and Modelling: A Survey. Chapter 23 in The Freshwater Budget of the Arctic Ocean, E.L. Lewis et al. (eds.), Kluwer, 549-587.

Fyfe, J.C., G.J. Boer, and G.M. Flato. 1999: The Arctic and Antarctic Oscillations and their Projected Changes Under Global Warming. Geophys. Res. Lett., 26, 1601-1604.

Hanesiak, J.M., D.G. Barber, and G.M. Flato. 1999. The role of diurnal processes in the seasonal evolution of sea ice and its snow cover. J. Geophys. Res., 104, 13593- 13604.

Fyfe, J.C. and G.M. Flato. 1999. Enhanced climate change and its detection over the Rocky Mountains. J. Clim., 12:230-243.

Goodison, B.E., R.D. Brown, M.M. Brugman, C.R. Duguay, G.M. Flato, E.F. LeDrew, and A.E. Walker, 1999: CRYSYS - Use of the cryospheric system to monitor global change in Canada: Overview and progress. Canadian Journal of Remote Sensing, 25, 3-11.

Flato, G.M. 1998. The thickness variable in sea-ice models. Atmos.-Ocean, 36(1): 29-36.

Randall, D., J. Curry, D. Battisti, G. Flato, plus 6 others. 1998. Status and outlook for large-scale modeling of atmosphere-ice-ocean interactions in the Arctic. Bull. Am. Meteorol. Soc., 79(2):197-217.

Flato, G.M. and D. Ramsden. 1997. Sensitivity of an atmospheric general circulation model to the parameterization of leads in sea-ice. Annals of Glaciology, 25:96- 101.

Lemke, P., W.D. Hibler III, G.M. Flato, M. Harder, and M. Kreyscher. 1997. On the improvement of sea ice models for climate simulations: The sea ice model intercomparison project. Annals of Glaciology, 25:183-187.

Flato, G.M. and R.D. Brown. 1996. Variability and climate sensitivity of landfast Arctic sea ice. J. Geophys. Res., 101(C10):25,767-25,777.

Flato, G.M. and W.D. Hibler III. 1995. Ridging and strength in modelling the thickness distribution of Arctic sea ice. J. Geophys. Res., 100(C9):18,611-18,626.

Flato, G.M. 1995. Spatial and temporal variability of Arctic ice thickness. Annals of Glaciology, 21:323-329.

Flato, G.M. 1994. Review of: "Microwave Remote Sensing of Sea Ice". Bull. Am. Meteorol. Soc., Vol. 75, No. 5, pp.866-868. [Invited Book Review]

Tang, B., G.M. Flato, and G. Holloway. 1994. A study of Arctic sea ice and sea level pressure using POP and neural network methods. Atmos.-Ocean, 32, 507-529.

Flato, G.M. 1993. A particle-in-cell sea-ice model. Atmos.-Ocean, 31, 339-358.

Flato, G.M. and W.D. Hibler III. 1992. Modeling pack ice as a cavitating fluid. J. Phys. Oceanogr., 22, 626-651.

Hibler, W.D. III and G.M. Flato. 1992. Sea Ice Models. Chapter 12 in Climate System Modeling, K.E. Trenberth (ed.), Cambridge University Press.

Ip, C.F., W.D. Hibler III, and G.M. Flato. 1991. On the effect of rheology on seasonal sea ice simulations. Annals of Glaciology, 15, 17-25.

Flato, G.M. and W.D. Hibler III. 1991. An initial numerical investigation of the extent of sea ice ridging. Annals of Glaciology, 15, 31-36.

Hopkins, M.A., W.D. Hibler III, and G.M. Flato. 1991. On the numerical simulation of the sea ice ridging process. J. Geophys. Res., 96, 4809-4820.

Flato, G.M. and W.D. Hibler III. 1990. On a simple sea ice dynamics model for climate studies. Annals of Glaciology, 14, 72-77.

Flato, G.M. and W.D. Hibler III. 1989. The effect of ice pressure on marginal ice zone dynamics. IEEE Trans. on Geoscience and Remote Sensing, 27, 514-521.