Department of Geography
Robert C. Brown Hall (RCB 6238)
Simon Fraser University, Department of Geography, August 2010 – Present
Adjunct Assistant Professor
University of Victoria, School of Earth and Ocean Sciences, Victoria, BC,
July 2009 – Present
Environment Canada, Canadian Centre for Climate Modelling and Analysis, Victoria, BC, November 2008 – July 2010
Postdoctoral Research Associate,
University of Victoria, School of Earth and Ocean Sciences, Victoria, BC
Postdoctoral Research Associate,
Potsdam Institute for Climate Impact Research, Potsdam, Germany (2005)
Potsdam University, Potsdam, Germany (2004)
Free University Berlin, Berlin, Germany (1998)
My research focuses on the effects of anthropogenic emissions of greenhouse gases and aerosols on climate on centennial to millennial timescales. The goal is to better understand the response of the climate system to forcing and the interactions between the different climate system components (the atmosphere, ocean, land surface, biosphere and cryosphere) in order to improve predictions for the future. To achieve this objective, I use climate models of different complexity, from simple conceptual models to complex Earth System models.
Feedbacks between climate and the carbon cycle
There are a range of climate feedbacks which have the potential attenuate or exacerbate climate change in the future. One class of feedbacks concerns the carbon cycle, and determines how much of the carbon dioxide emitted by human activities remains in the atmosphere. For example, the solubility of carbon dioxide (CO2) in seawater decreases with temperature, so if the temperature of seawater rises, the ocean will be able to absorb less CO2. Similar feedbacks also exist for the terrestrial carbon cycle (i.e. vegetation and soils). Current research suggests that the total effects of climate carbon-cycle feedbacks on land and in the ocean is to amplify climate change (i.e a positive feedback). I am interested in better understanding and quantifying these feedbacks using climate models.
Reversibility of human-induced climate change
Is global warming reversible, i.e. is it possible to revert the climate system to a previous state if human-induced emissions of greenhouse gases are reduced or completely eliminated? Irreversibility in the climate system is caused by the long (centennial to millennial) residence time of CO2 in the atmosphere, and the long reaction timescales of the deep ocean and ice sheets (”climate system inertia”). Recent research has shown that climate change is largely irreversible (i.e. temperature will remain elevated and sea level will continue to rise) for several centuries even after human-induced emissions of greenhouse gases are stopped entirely. New technology is being tested which allows one to artificially remove carbon dioxide from the atmosphere (so-called “carbon dioxide removal” technology). I am interested in exploring whether carbon dioxide removal technology has the potential to enhance the reversibility of the climate system, given realistic constraints on the rate and scale this technology can be applied at.
The United Nations Framework Convention on Climate Change (UNFCCC) commits signatory nations to stabilization of CO2 in the atmosphere in order to avoid “dangerous anthropogenic interference” with the climate system. However, the UNFCCC does not specify what “dangerous” means. Based on the work of the climate research community, many nations and environmental organizations have adopted 2 degrees of warming above pre-industrial levels as a target at which global warming should be capped. I am interested in exploring whether there are critical thresholds or “tipping points” in the climate system which may lead to a significantly different climate in large regions of Earth and whose effects may be irreversible. The research questions I am interested in are: What level of global warming would trigger these tipping points? Does a 2 degree target safeguard against crossing critical thresholds/tipping points in the climate system? I am also interested in quantifying the “carbon budget” compatible with meeting specific climate targets.
Graduate student opportunities
The Climate Research Lab at SFU is currently seeking Masters and Doctoral students interested in pursuing research on past and future climate change using Earth System models.
Click here for info on potential research projects and application procedure.
Publications in refereed journals
31. Herrington, T., and K. Zickfeld, 2014, Path independence of climate and carbon cycle response over a broad range of cumulative carbon emissions, Earth Syst. Dynam., 5: 409-422.
30. Eby, M., A.J. Weaver, K. Alexander, K. Zickfeld et al., 2013, Historical and idealized climate model experiments: An intercomparison of Earth system models of intermediate complexity, Climate of the Past 9(3): 1111-1140, doi: 10.5194/cp-9-1111-2013.
29. Zickfeld, K., M. Eby, K. Alexander, A.J. Weaver et al., 2013, Long-term climate change commitment and reversibility: An EMIC intercomparison, Journal of Climate 26(16):5782-5809, doi: 10.1175/JCLI-D-12-00584.1.
28. Weaver, A.J., Jan Sedlácek, M. Eby, K. Alexander, E. Crespin, T. Fichefet, G. Philippon-Berthier, F. Joos, M. Kawamiya, K. Matsumoto, M. Steinacher, K. Tachiiri, K. Tokos, M. Yoshimori, K. Zickfeld, 2012, Stability of the Atlantic Meridional Overturning Circulation: A Model Intercomparison, Geophysical Research Letters, 39, L20709, doi:10.1029/2012GL053763.
27. Kvale, K.F., K. Zickfeld, T. Bruckner, K.J. Meissner, K. Tanaka, and A.J. Weaver, 2012, Carbon dioxide emissions pathways avoiding dangerous ocean impacts, Weather, Climate and Society, 4, 212-292, doi: 10.1175/WCAS-D-11-00030.1.
26. Zickfeld, K., V.K Arora, and N.P. Gillett, 2012, Is the climate response to carbon emissions path dependent? Geophysical Research Letters. 39, L05703, doi:10.1029/2011GL050205.
25. Matthews, H.D., and K. Zickfeld, 2012, Climate response to zeroed emissions of greenhouse gases and aerosols, Nature Climate Change 2, 338-341.
24. Zickfeld, K., M. Eby, H.D. Matthews, A. Schmittner, and A.J. Weaver, 2011, Nonlinearity of carbon cycle feedbacks, Journal of Climate 24(6): 4254-4274.
23. Gillett, N.P., V. Arora, K. Zickfeld, S. Marshall, and B. Merryfield, 2011, Ongoing climate change following a complete cessation of carbon dioxide emissions, Nature Geoscience, 4:83–87.
22. Zickfeld, K., M.G. Morgan, D.J. Frame, and D.W. Keith, 2010, Expert judgments about transient climate response to alternative future trajectories of radiative forcing, Proceedings of the National Academy of Science, 107 (28): 12451-12456.
21. Kuhlbrodt, T., S. Rahmstorf, K. Zickfeld, F. Vikebø, S. Sundby, M. Hofmann, P.M. Link, A. Bondeau, W. Cramer, and C. Jaeger, 2009, An Integrated Assessment of Changes in the Thermohaline Circulation,Climatic Change, 96, 489-537
20. Zickfeld, K., M. Eby, H.D. Matthews, and A.J. Weaver, 2009, Setting cumulative emissions targets to reduce the risk of dangerous climate change, Proceedings of the National Academy of Science, 106(38): 16129-16134.
19. Eby, M., K. Zickfeld, A. Montenegro, D. Archer, K.J. Meissner, and A.J. Weaver, 2009, Lifetime of anthropogenic climate change: Millennial life-times of potential CO2 and temperature perturbations,Journal of Climate, 22: 2501-2511.
18. Matthews, H.D., N. Gillett, P. A. Stott, and K. Zickfeld, 2009, The proportionality of global warming to cumulative carbon emissions, Nature, 459: 829-833.
17. Bruckner, T., and K. Zickfeld, 2009, Low risk emissions corridors for safeguarding the Atlantic thermohaline circulation, Mitigation and Adaptation Strategies for Global Change, 14, 61-83.
16. Zickfeld, K., and T. Bruckner, 2008, Reducing the risk of Atlantic thermohaline circulation collapse: sensitivity analysis of emissions corridors. Climatic Change, 91, 291-315.
15. Zickfeld, K., M. Eby, and A.J. Weaver, 2008, Carbon-cycle feedbacks of changes in the Atlantic meridional overturning circulation under future atmospheric CO2, Global Biogeochem. Cycles, 22, GB3024.
14. Zickfeld, K., J.C. Fyfe, M. Eby, and A.J. Weaver, 2008, Comment on “Saturation of the Southern Ocean CO2 sink due to recent climate change”. Science, 319, 570b.
13. Knopf, B., K. Zickfeld, M. Flechsig, and V. Petoukhov, 2008, Sensitivity of the Indian monsoon to human activities. Advances of Atmospheric Sciences, 25(6), 932-945.
12. Weaver, A.J., K. Zickfeld, A. Montenegro, and M. Eby, 2007, Long term climate implications of 2050 emission reduction targets. Geophysical Research Letters, 34, L19703.
11. Zickfeld, K., O.A. Saenko, M. Eby, J.C. Fyfe, and A.J. Weaver, 2007, Response of the global carbon cycle to human-induced changes in Southern Hemisphere winds. Geophysical Research Letters, 34, L12712.
10. Fyfe, J.C., O.A. Saenko, K. Zickfeld, M. Eby, and A.J. Weaver, 2007, The role of poleward intensifying winds on Southern Ocean warming. Journal of Climate, 20: 5391-5400.
9. Zickfeld, K., A. Levermann, M.G. Morgan, T. Kuhlbrodt, S. Rahmstorf, and D.W. Keith, 2007, Expert judgments on the response of the Atlantic meridional overturning circulation to climate change. Climatic Change, 82(3-4): 235-265.
8. Knopf, B., M. Flechsig, and K. Zickfeld, 2006, Multi parameter uncertainty analysis of a bifurcation point. Nonlinear Processes in Geophysics, 13: 531-540.
7. Kropp, J.P., A. Block, F. Reusswig, K Zickfeld, and H.-J. Schellnhuber, 2006, Semiquantitative Assessment of Regional Climate Vulnerability: The North Rhine - Westphalia Study. Climatic Change, 76(3-4): 265-290.
6. Zickfeld, K., B. Knopf, V. Petoukhov, and H.-J. Schellnhuber, 2005, Is the Indian summer monsoon stable against global change?, Geophysical Research Letters, 32, L15707.
5. Rahmstorf, S., and K. Zickfeld, 2005, Thermohaline circulation changes: a question of risk assessment, Climatic Change, 68 (1-2): 241-247.
4. Zickfeld, K., T. Slawig and S. Rahmstorf, 2004, A low-order model for the response of the Atlantic thermohaline circulation to climate change, Ocean Dynamics, 54(1): 8-26.
3. Slawig, T., and K. Zickfeld, 2004, Parameter optimization using algorithmic differentiation in a reduced-form model of the Atlantic thermohaline circulation, Nonlinear Analysis: Real World Applications, 5(3): 501-518.
2. Zickfeld, K., and T. Bruckner, 2003, Reducing the risk of abrupt climate change: emissions corridors preserving the Atlantic thermohaline circulation, Integrated Assessment, 4(2): 106-115.
1. Zickfeld, K., M.E. Garcia, and K.H. Bennemann, 1999, Theoretical study of the laser-induced femtosecond dynamics of small Sin clusters, Phys. Rev. B, 59(20): 13422-13430.
Intergovernmental Panel on Climate Change (IPCC)
Contributing author to:
Church, J.A., P.U. Clark et al., 2013, Chapter 13: Sea Level Change, in: T.F. Stocker and D. Qin (Eds.): Climate Change 2013: The Physical Science Basis, Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, 1137-1216.
Collins, M., R. Knutti et al., 2013, Chapter 12: Long-term Climate Change: Projections, Commitments and Irreversibility, in: T.F. Stocker and D. Qin (Eds.): Climate Change 2013: The Physical Science Basis, Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, 1029-1136.
Smith, J.B., H.-J. Schellnhuber, M.Q. Mirza, S. Fankhauser, R. Leemans, L. Erda, L. Ogallo, B. Pittock, R. Richels, C. Rosenzweig, U. Safriel, R.S.J. Tol, J. Weyant, G. Yohe, 2001, Vulnerability to Climate Change and Reasons for Concern: A Synthesis, in: J.J. McCarthy, O.F. Canziani, N.A. Leary, D.J. Dokken, K.S. White (Eds.): Climate Change 2001: Impacts, Adaptation, and Vulnerability, Contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, 913-967.
Kropp, J., K. Zickfeld, and K. Eisenack, 2002, Assessment and management of critical events: The breakdown of marine fisheries and the North Atlantic thermohaline circulation. In: A. Bunde, J. Kropp, H.J. Schellnhuber (Eds.), The science of disaster: climate disruptions, heart attacks, and market crashes, Springer, Berlin Heidelberg, 193-216.
Articles in conference proceedings
Bruckner, T., and K. Zickfeld, 2008, Inverse integrated assessment of climate change: the guardrail approach, International conference on policy modelling, July 2-4 2008, Berlin, Germany.
Bruckner, T., and K. Zickfeld, 2004, Low risk emissions corridors for safeguarding the Atlantic thermohaline circulation, Expert Workshop on “Greenhouse gas emissions and abrupt climate change: positive options and robust policy”, October 30 – October 1, 2004, Paris, France.
Zickfeld, K., and T. Bruckner, 2002, Emissions corridors preserving the Atlantic Ocean thermohaline circulation, In: A. E. Rizzoli, A.J. Jakeman (Eds.), Integrated assessment and decision support - Proceedings of the 1st biennial meeting of the International Environmental Modelling and Software Society, 24-27 June 2002, Lugano, Switzerland, 145-150.
GEOG 214 Weather and Climate
This course provides an introduction to the fundamental principles and processes governing the Earth’s weather and climate. Topics include radiation, energy balance, greenhouse effect, clouds, precipitation, atmospheric circulation, mid-latitudes cyclones, thunderstorms, tornadoes, climate change, air pollution and ozone hole.
GEOG 314 The Climate System
This course examines the climate system and its components – the atmosphere, ocean and land surface. Emphasis will be placed on the physical and biogeochemical interactions between these components. Topics to be covered include: atmospheric processes relevant to climate, role of the ocean and land surface in climate, carbon cycle, climate feedbacks, history and evolution of Earth’s climate, global warming, climate models.
GEOG 414 Climate Change
This course provides an overview of the climate change/global warming issue, with focus on the scientific foundations but also consideration of its societal implications. Topics to be discussed include observations of climate changes, attribution of climate changes to natural and/or anthropogenic causes, climate models, sources of greenhouse gas emissions, 21st century projections of future climate changes at regional and global scales, long-term climate changes, biophysical and socio-economic impacts, vulnerability, adaptation to climate change, mitigation of greenhouse gas emissions, geoengineering, climate stabilization, international climate policy.