Canadian Foundation for Climate and Atmospheric Sciences

Progress Report:

GR-201 — Vegetation/Carbon Cycle Feedbacks on Quaternary Climate

June 24, 2003

This progress report is available on the world wide web at:

1: Principal Investigator

Andrew Weaver

2: Institution

School of Earth & Ocean Sciences, University of Victoria

PO Box 3055,Victoria, BC, V8W 3P6

3: Milestones and progress towards their completion

There were eight milestones as part of this project and we are well ahead of schedule in that the model development milestones (1, 2 and 3) are now completed. We have also completed milestone 4 (see publications 34 and 37) and 5 (see publication 33) a year ahead of schedule. All the experiments for milestone 7 have been completed and we expect to submit a manuscript in this area this summer. We have gone much further than originally proposed as our climate model now includes a fully interactive terrestrial and ocean (biology and chemistry) carbon cycle model. I was very fortunate to have been awarded a Killam Fellowship last year which has allowed me to spend 100% of my time on my research. This has allowed us to move forward in our research agenda at a much faster pace than originally planned.

Tracy Ewen, a PhD student, working on this project has nearly completed her PhD and will defend her thesis in the fall of this year.

Damon Matthews, a truly oustanding student transferred from MSc to PhD program and has nearly finished his PhD. He too will defend his PhD thesis in the fall (in 3 years).

Other students who worked on this CFCAS funded research: Melanie Cottet Puinel (MSc), Jeff Lewis (MSc) have now graduated.

Two postdocs who were funded off the CFCAS grant (Andreas Schmittner and Katrin Meissner) have both taken up faculty positions (Andreas at the University of Kiel in Germany and Katrin at the University of Victoria). Taken together, CFCAS funding has provided a remarkable opportunity for the training of highly qualified personelle.

I was asked to give a plenary presentation at the IUGG conference in July of this year. As part of this Plenary Union Session (State of the Planet), I was tasked with reviewing the progress towards understanding the role of the ocean’s thermohaline circulation in climate: past, present and future. I am enclosing a copy of the body of this review which will be published in an AGU monograph series as it is essentially a review of my CFCAS funded research over the last two years.

By the end of the next year, I will have completed all milestones and have examined the importance of the ocean and terrestrial carbon cycle on climate change over the last 135,000 years. We will then use the UVic model as the foundation for a model-based integrated assessment proposal which we will submit to CFCAS in the next competition. I have accepted a PhD student in this regard and have started exploratory collaborations with researchers in NRCan, Australia and Switzerland in this area. Our goal will be to develop a tool which will allow us to explore the climatic and socioeconomic responses to various policy options. This work will be collaborative with another CRC Chair at UVic (C. van Kooten) and will involve coupling a computable general equilibrium economic model into the UVic ESCM.

4:      Publications: 2002-2003, in press and submitted

Attached is a list of 2002-2003 publications as well as those are in press or recently submitted. All publications directly supported by CFAS are indicated with a bold number. Several CFCAS funded articles has already appeared including two in the high profile journal Science. CFCAS funding is acknowledged in all papers that were supported by GR-201 research grant funds.


1. Yoshimori, M., M.C. Reader, A.J. Weaver and N.A. MacFarlane, 2002: On the causes of glacial inception at 116KaBP. Climate Dynamics, 18, 383–402.

2. Clark, P.U., N.G. Pisias, T.F. Stocker, and A.J. Weaver, 2002: The role of the thermohaline circulation in abrupt climate change. Nature, 415, 863–869.

3.Schmittner, A., M. Yoshimori and A.J. Weaver, 2002: Instability of glacial climate in a model of the ocean-atmosphere-cryosphere system. Science, 295, 1489–1493.

4. Claussen, M., L. A. Mysak, A. J. Weaver, M. Crucifix, T. Fichefet, M.-F. Loutre, S. L. Weber, J. Alcamo, V.A. Alexeev, A. Berger, R. Calov, A. Ganopolski, H. Goosse, G. Lohmann, F. Lunkeit, I.I. Mokhov, V. Petoukhov, P. Stone and Z. Wang, 2002: Earth system models of intermediate complexity: Closing the gap in the spectrum of climate system models. Climate Dynamics, 18, 579–586.

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

6. Schmittner, A., K.J. Meissner, M. Eby and A. J. Weaver, 2002: Forcing of the deep ocean circulation in simulations of the Last Glacial Maximum. Paleoceanography, 17(2), 5:1–5:15, 1015, doi:10.1029/2001PA000633.

7. Stone, D.A., and A.J. Weaver, 2002: Daily maximum and minimum temperature trends in a climate model. Geophysical Research Letters, 29(9), 70:1–70:4, 1356, doi:10.1029/2001GL014556.

8. Meissner, K.J., A. Schmittner, E.C. Wiebe and A.J. Weaver, 2002: Simulations of Heinrich Events in a coupled ocean-atmosphere-sea ice model. Geophysical Research Letters29(14), 16:1–16:3, 1671, doi:10.1029/2001GL013514.

9. McLaughlin, F.A., E. Carmack, R. Macdonald, A.J. Weaver and J. Smith, 2002: The Canada Basin 1989-1995: Upstream events and far-field effects of the Barents Sea. Journal of Geophysical Research107(C7), 19:1–19:20, 3082, doi:10.1029/2001JC000904.

10. de Vernal, A., C. Hillaire-Marcel, W.R. Peltier and A.J. Weaver, 2002: The structure of the upper water column in the northwest North Atlantic: Modern vs. last glacial maximum conditions. Paleoceanography, 17(4), 2:1–2:15, 1050, doi:10.1029/2001PA000665.

11. Gillett, N.P., F.W. Zwiers, A.J. Weaver, G.C. Hegerl, M.R. Allen and P.A. Stott, 2002: Detecting anthropogenic influence with a multi model ensemble. Geophysical Research Letters, 29(20), 31:1–31:4, 1970, doi:10.1029/2002GL015836.

12. Saenko, O.A., A. Schmittner, and A.J. Weaver, 2002: On the role of wind-driven sea ice motion on ocean ventilation. Journal of Physical Oceanography, 32, 3376–3395.

13. Saenko, O.A., J.M. Gregory, A.J. Weaver and M. Eby, 2002: Distinguishing the influence of heat, freshwater and momentum fluxes on ocean circulation and climate. Journal of Climate, 24, 3686–3697.


14.    Matthews, H.D., A.J. Weaver, M. Eby and K.J. Meissner, 2003: Radiative forcing of climate by historical land cover change. Geophysical Research Letters, 30(2), 27:1–27:4, 1055, doi:10.1029/2002GL016098.

15. Saenko, O.A., and A.J. Weaver, 2003: Southern Ocean upwelling and eddies: Sensitivity of the global overturning to the surface density range. Tellus, 55A, 106–111.

16.Weaver, A.J., O. A. Saenko, P.U. Clark, and J. X. Mitrovica, 2003: Meltwater pulse 1A from Antarctica as a trigger of the Bølling-Allerød warm interval. Science, 299, 1709–1713.

17.Hill, K.L., A.J. Weaver, H.J. Freeland and A. Bychkov, 2003: Evidence of change in the Sea of Okhotsk: Implications for the North Pacific. Atmosphere-Ocean, 41, 49–63.

18. Stone, D.A. and A.J. Weaver, 2003: Factors contributing to diurnal temperature range trends in twentieth and twenty-first century simulations of the CCCma coupled model. Climate Dynamics, 20, 435-445.

19. Gillett, N.P., F.W. Zwiers, A.J. Weaver and P.A. Stott, 2003: Detection of human influence on sea level pressure. Nature, 422, 292–294.

20. Schmittner, A., O.A. Saenko, and A.J. Weaver, 2003: Coupling of the hemispheres in observations and simulations of glacial climate change. Quaternary Science Reviews, 22, 659–671.

21. Meissner, K.J., A. Schmittner, A.J. Weaver and J.F. Adkins, 2003: The ventilation of the North Atlantic Ocean during the Last Glacial Maximum — A comparison between simulated and observed radiocarbon ages. Paleoceanography, 18(2), 1:1–1:13, 1023, doi:10.1029/2002PA000762.

22. Saenko, O.A., A.J. Weaver and M.H. England, 2003: A region of enhanced northward Antarctic intermediate water transport in a coupled climate model. Journal of Physical Oceanography, 33, 1528–1535.

In press:

23. Saenko, O.A., E.C. Wiebe, and A.J. Weaver, 2003: North Atlantic response to the above-normal export of sea-ice from the Arctic. J. Geophys. Res., in press.

24. National Research Council, 2003: Climate Change Feedbacks: Characterizing and Reducing Uncertainties, National Academy Press, 130pp, in press.

25. Simmons, H.L., S.R. Jayne, L.C. St. Laurent and A.J. Weaver, 2003: Tidally driven mixing in a numerical model of the ocean general circulation. Ocean Modelling, in press.

26. Cottet-Puinel, M., A.J. Weaver, C. Hillaire-Marcel, A. de Vernal, P.U. Clark and M. Eby, 2003: Variation of Labrador Sea water formation over the last glacial cycle in a climate model of intermediate complexity. Quaternary Science Reviews, in press.

27. Saenko, O.A., A.J. Weaver, and J.M. Gregory, 2003. On the link between the two modes of the ocean thermohaline circulation and the formation of global-scale water masses. Journal of Climate, in press.

28. Coward, H.G., and A.J. Weaver, 2003: Hard Choices: Climate Change in Canada. Wilfred Laurier Press, Waterloo, Ontario, Canada, in press.

29. Weaver, A.J., 2003: The science of climate change. In: Hard Choices: Climate Change in Canada. Coward, H.G., and A.J. Weaver, Eds. Wilfred Laurier Press, Waterloo, Ontario, Canada, in press.

30.   Weaver, A.J., 2003: The science of climate change, Geoscience Canada, in press.

31.     Saenko, O.A., A.J. Weaver and A. Schmittner, 2003: Atlantic deep circulation controlled by freshening in the Southern Ocean. Geophysical Research Letters, in press.

32. Gregory, J.M.., O.A. Saenko, and A.J. Weaver, 2003: The role of the Atlantic freshwater balance in the hysteresis of the meridional overturning circulation. Climate Dynamics, in press.

33. Meissner, K.J., A.J. Weaver, H.D. Matthews, and P.M. Cox, 2003: The role of land-surface dynamics in glacial inception: A study with the UVic Earth System Model. Climate Dynamics, in press.


34.Ewen, T.L., A.J. Weaver and M. Eby, 2003: Sensitivity of the inorganic ocean carbon cycle to future climate warming in the UVic coupled model. Atmosphere-Ocean, submitted.

35.Lewis, J.P., A.J. Weaver, S.T. Johnston and M.Eby, 2003: The Neoproterozoic ‘Snowball Earth’: Dynamic ice over a quiescent ocean. Paleoceanography, submitted.

36. 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. Geophysical Research Letters, submitted.

37.    Ewen, T., A.J. Weaver, and A. Schmittner, 2003: Modelling carbon cycle feedbacks during abrupt climate change. Quaternary Science Reviews, submitted.

38.    Matthews, H.D., A.J. Weaver, K.J. Meissner, N.P. Gillett and M. Eby, 2003: Natural and anthropogenic climate change: Incorporating historical land cover change, vegetation dynamics and the global carbon cycle. Climate Dynamics, submitted.

39.    Clark, P.U., A.M. McCabe, A.C. Mix, and A.J. Weaver, 2003: The 19-kyr B.P. meltwater pulse and its global implications. Nature, submitted.

Public Outreach

Over the years my research has been the focus of many newspaper and magazine stories and I have conducted numerous TV and Radio interviews. Two particularly relevant pieces appeared in Time Magazine over the last year. These stories highlight the CFCAS funded work that I have done in the area of paleoclimate modelling and analysis. They point to my two ultimate goals being: 1) “to produce a detailed simulation of the earth’s climate for the past 135,000 years with unparalleled precision” (Time Magazine Canadian Edition, November 18th 2002, page 79); 2) “to examine the influence of climate on human evolution over the past 130,000 years” (Time Magazine Canadian Edition, February 17th 2003, page 49). The latter Time Magazine article was written as part of my selection by Time Canada as one of the top 5 Canadian Scientists.

UVic / SEOS / Climate Group / Research Funding / CFCAS Progress June 2003 Last updated: