Andrew J. Weaver, School of Earth and Ocean Sciences, University of Victoria
2. Title of Project and Application Number
The role of the ocean in climate change and climate variability: STP0192999
3. Co-investigators, Department, Institution
4. Budget Amount Total NSERC Total Cash Contribution Total In-Kind Awarded by Expenditure to date Provided by all Partners Contribution Provided by NSERC all Partners Year 1 $166,000 $166,000 $240,940 $10,000 Year 2 $151,000 $97,180 $120,355 $339,537 Year 3 N/A N/A $121,610 N/A5. Amount remaining in grant as of May 31: $??????????
I have listed the amount remaining at the end of May instead of June as I will be unable to obtain the requested information prior to the July 15th deadline. My wife and I are expecting a baby during the last week of June and I am taking holidays for 3 weeks at that time. If NSERC wishes, I could provide this figure towards the end of July.
6. Achievement of the Objectives Described in the Original Application
In my original proposal I listed 8 objectives and 11 milestones aimed at meeting these objectives. The original objectives are given below and at the end of each objective I specify the relevant milestone. The remainder of this section then discusses progress as per each milestone. A review of the role of the ocean in climate variability was also written upon invitation from Annual Review of Earth and Planetary Sciences (Weaver et al, 1998a).
1 understand processes of decadal-interdecadal variability using a coupled OGCM-EMBM-TIM. The OGCM [ocean general circulation model] will have variable resolution ranging from 4deg. to 0.25deg. (Milestone #4).
2 understand the role of eddies in the poleward transport of heat and salt. (Milestone #1).
3 use CFC-11 as a tracer to validate the climatology of OGCMs as well as their sub-grid scale mixing parameterizations. (Milestone #5).
4 develop simple models to understand the processes involved in decadal-interdecadal climate variability. (Milestone #10).
5 investigate the effects of sub-grid-scale OGCM parameterizations on decadal-interdecadal climate variability. (Milestone #6).
6 use a global OGCM and coupled OGCM-EMBM-TIM to examine teleconnections associated with processes in the North Atlantic. (Milestone #9).
7 use the GFDL coupled model and the coupled EMBM-OGCM-TIM to investigate processes of decadal-interdecadal variability in the coupled climate system and its dependence on the mean climatic state. (Milestones #7 and 8)
8 undertake a simulation of the Younger Dryas event using the coupled EMBM-OGCM-TIM. In addition the climatic effects of opening and closing oceanic gateways will be examined. (Milestones #2 and 3).
1. Analysis of the role of eddies in transporting heat and freshwater poleward -- Completed 30/06/1997
A coupled ocean-atmosphere model was used to study the influence of horizontal resolution and parameterized eddy processes on the poleward heat transport in the climate system. A series of experiments ranging from 4deg. to 0.25deg. resolution were performed. Our results contradicted earlier studies which showed that the heat transport associated with time varying circulations counteracts increases in the time mean so that the total remained unchanged as resolution was increased. To interpret our results, the oceanic heat transport was decomposed into its baroclinic overturning (related to the meridional overturning and Ekman transports), barotropic gyre (in the horizontal plane) and baroclinic gyre (associated with the core of the western boundary current) components. The increase in heat transport occurred in the steady currents. In particular the baroclinic gyre transport increased by a factor of 5 from the coarsest to the finest resolution case, equaling the baroclinic overturning transport at mid-high latitudes. To further assess the results, a parallel series of experiments under restoring conditions were performed to elucidate the differences between heat transport in coupled vs uncoupled models, and models driven by temperature and salinity or equivalent buoyancy. Although heat transport was more strongly constrained in the restoring experiments, results were similar to those in the coupled model. These results point to the importance of higher resolution in the oceanic component of current coupled climate models and stress the need to adequately represent the heat transport associated with the Warm Core region of the Gulf Stream (the baroclinic gyre transport) in order to adequately represent oceanic poleward heat transport. Published in Fanning and Weaver (1997b).
2. Simulation of the Younger Dryas event -- Completed 30/06/1997
The temporal and geographical roles of meltwater discharge (from the Laurentide ice sheet) on North Atlantic Deep Water (NADW) production were investigated using a global coupled model. Model results suggested that preconditioning by meltwater discharge (to the Mississippi) prior to the Younger Dryas (YD) was capable of pushing NADW beyond the limit of its sustainability. The diversion of meltwater to the St. Lawrence then served to inhibit NADW production. The modeled change in surface air temperature (SAT) generally agreed with the global pattern and magnitude of change seen in paleoclimatic reconstructions of the YD and was linked to changes in NADW formation. The thermohaline circulation provided an interhemispheric teleconnection with the Southern Ocean, while changes in the atmospheric heat transport provided a mechanism for interbasin teleconnection. The inclusion of a wind stress/speed feedback was found to contribute to the resumption of NADW production, as suggested by previous studies. Contrary to these studies the coupled model indicated that an advective spin-up timescale was required for resumption of NADW production and hence the termination of the modeled YD-like climate event (as opposed to a decadal-century timescale). Published in Fanning and Weaver (1997a).
3. Climatic effects of opening and closing oceanic gateways-- Completed 31/10/1997
The paleoclimatic effects of the closure of the Isthmus of Panama ~3 million years ago were investigated using our coupled model. Consistent with earlier ocean-only modelling studies, it was shown that prior to the closing of the Isthmus of Panama, NADW formation did not occur. Associated with the absence of NADW formation was a reduction in both the Atlantic and global oceanic heat transports. This reduction in oceanic heat transport was largely compensated for by an increase in the atmospheric heat transport, with the result that only small changes in total planetary heat transport occurred. Model results suggested that the present-day climate of the North Atlantic is significantly warmer than before the closure of the Isthmus. In addition, the regions surrounding the Pacific Ocean and South Atlantic are generally cooler while the Indian Ocean is generally warmer in the present-day climate simulation. Published in Murdock et al (1997).
While this particular component of the strategic research is now complete, funding has been received under the NSERC Climate System History and Dynamics project to carry on important follow-up research. M. Yoshimori, a PhD student, is focusing on the interaction of the cryosphere, atmosphere and ocean. We are presently incorporating the continental ice sheet model, developed by Marshall and Clarke at UBC, into our coupled atmosphere-ocean-sea ice model. The ice sheet/climate model will be used to: 1)-- examine the transition from the Last Glacial Maximum (see Weaver et al, 1998b) to the Holocene. This involves the integration of the coupled system from 21KBP to 6KBP under changing orbital forcing. 2)-- examine whether or not the onset of northern hemisphere glaciation can be attributed to the closure of the Isthmus of Panama ~ 3million years ago
4. Understand processes of decadal variability in coupled OGCM-EMBM-TIM -- In progress
An idealized coupled model was used to study the influence of horizontal resolution and parameterized eddy processes on the thermohaline circulation. A series of experiments ranging from 4deg. to 0.25deg. resolution were performed for both coupled and ocean-only models. Spontaneous internal variability (primarily on the decadal time-scale) was found to exist in the higher resolution cases. The decadal variability was described via an advective-convective mechanism which is thermally driven, and linked to the value of the horizontal diffusivity used in the model. Increasing the diffusivity in the high resolution cases was enough to destroy the variability, while decreasing the diffusivity in the moderately coarse resolution cases was capable of inducing decadal-scale variability. As the resolution was increased still further, baroclinic instability within the western boundary current added a stochastic component to the solution such that the variability was less regular and more chaotic. These results point to the importance of higher resolution in the ocean component of coupled models, revealing the existence of richer variability in models which require less parameterized diffusion. Published in Fanning and Weaver (1998).
Work has not finished in this area as we and our partners (CICS and CCCma), have recently become excited about understanding low frequency variability of the North Atlantic Oscillation (NAO). Our conjecture is that sea ice plays an important role in this variability. In order to examine this issue, several improvements have been incorporated into the sea ice component of our coupled model. These include a parameterization of sea ice dynamics and a subgrid-scale ice thickness distribution. Self-sustained oscillations involving sea-ice appear possible in the model, although more work is needed to examine the sensitivity of these oscillations to internal parameterizations.
The impact of ice export on climate variability is also being addressed by applying an anomalous wind stress forcing in the coupled model. The model reveals significant decadal variability when the wind stress field includes interannual variability at high latitudes (north of 60deg.) and over the North Atlantic Ocean. The interannually varying wind stress field was derived from NCEP reanalysis daily mean SLP data which is available for the last 40 years. The SLP data were separated into spatial modes using an EOF analysis and only the leading 20 modes were kept. C. Bitz and M. Holland (Research Associates) are focusing their efforts on this exciting research area.
5. CFC-11 and sub-grid-scale mixing parameterizations -- In progress
In attempting to address this objective we first had to overcome some numerical problems associated with the use of isopycnal and isopycnal thickness diffusion parameterizations for subgrid scale mixing associated with mesoscale eddies. It was shown that when the mixing tensor was rotated, so that mixing was primarily along isopycnals, numerical problems may occur and non-monotonic solutions which violate the second law of thermodynamics may arise when standard centred difference advection algorithms are used. These numerical problems can be reduced or eliminated if sufficient explicit (unphysical) background horizontal diffusion is added to the mixing scheme. A more appropriate solution is the use of more sophisticated numerical advection algorithms, such as the flux-corrected transport algorithm. This choice of advection scheme adds additional mixing only where it is needed to preserve monotonicity and so retains the physically-desirable aspects of the isopycnal and isopycnal thickness diffusion parameterizations, while removing the undesirable numerical noise. The price for this improvement is a computational increase. Published in Weaver and Eby (1997).
An ocean circulation model was also developed for a Cartesian coordinate flat-bottomed beta-plane, based on the planetary geostrophic (PG) equations, in order to test different parameterizations of the momentum dissipation (Laplacian, biharmonic, Rayleigh and none) and associated boundary conditions. The surface temperature fields and poleward heat transports were quite similar for the equilibrium states obtained using different momentum dissipation parameterizations. However, a comparison of the velocity fields and bottom water properties showed large discrepancies. Traditional Laplacian friction produced a more satisfying interior circulation, in better agreement with geostrophy and the Sverdrup balance, but generated excessively large vertical transports along the lateral boundaries. Rayleigh friction with a no-normal-flow boundary condition induced a more efficient thermohaline circulation with better agreement between convection regions and areas of downward velocities, colder deep water, much weaker meridional overturning and vertical transports along lateral boundaries, but higher poleward heat transport. Results from this parameterization were not as satisfying as the Laplacian closure in terms of interior geostrophic and Sverdrup balance. Nevertheless, it is an interesting alternative to implement it along with the no-normal-flow boundary conditions, since free-slip and no-slip boundary conditions were also shown to lead to very similar circulations, regardless of the momentum dissipation scheme. Published in Huck et al (1998b).
Recent measurements have shown that oceanic mixing varies with location, and tends to be an order of magnitude larger at ocean margins than in the thermocline. As a follow-up analysis, O. Dravnieks (a PhD student) is examining the effects of spatially varying vertical mixing parameterization on the global ocean circulation.
As mentioned in section 8, P. Duffy will spend August 1998 visiting my lab to examine the effects of various parameterizations for convection and plume dynamics in our coupled model. CFCs will be used in this analysis to validate the climatology from the various model integrations.
6. sub-grid-scale mixing parameterizations and decadal variability -- Completed 31/10/1997
Intrinsic modes of decadal variability were analysed using the PG ocean model. A complete parameter sensitivity analysis of the oscillatory behavior was carried out with respect to the spherical Cartesian geometry, the beta-effect, the Coriolis parameter, the parameterization of momentum dissipation and associated boundary conditions and viscosities, the vertical and horizontal diffusivities, the convective adjustment parameterization and the horizontal and vertical model resolution. The oscillation stood out as a robust feature whose amplitude was mainly controlled by the horizontal diffusivity. The analysis of the variability patterns differentiated two types of oscillatory behavior: temperature anomalies traveling westward in an eastward jet (northern part of the basin) inducing an opposite anomaly in their wake; temperature anomalies in the north-west corner which respond to the western boundary current transport changes, but reinforce this change and build the opposite temperature anomaly in the east, which finally reverse the meridional overturning anomaly (and thus the anomalous western boundary current transport). The analysis of the transition from steady to oscillatory states suggested, in agreement with a 1 1/2 layer model, that the variability was triggered in the regions of strongest cooling. Finally, we developed a simple box-model analogy that captured the observed phase-shift between meridional overturning and north-south density gradient anomalies. Published in Huck et al (1998a).
Flux adjustments are often used in coupled models to correct for missing parameterized or resolved physics. We examined the effect of using flux adjustments on the climatic response of our coupled model to an imposed radiative forcing. A linear reduction to the planetary longwave flux of 4 W/m2 was applied over a 70 year period and held constant thereafter. Similar model responses were found during the initial 70 year period for global-scale diagnostics of hemispheric SAT due to the nearly linear SAT response to the radiative forcing. Significant regional scale differences did however exist. As the perturbation away from the present climate grew, basin-scale diagnostics began to diverge between flux adjusted and non-flux adjusted models. Once the imposed radiative forcing was held constant, differences in global mean SAT of up to 0.5deg.C were found, with large regional-scale differences in SAT and overturning rates within the North Atlantic and Southern Ocean. Additional experiments with the flux adjusted model suggested the coupling shock could be reduced by running out the control integration before the radiative forcing was applied. Our results suggested that perturbation experiments should not be undertaken until after the coupled model control experiment is continued for several hundred years in order to minimize the coupling shock. In addition, care should be exercised in the interpretation of regional-scale results (over the ocean) and global-scale diagnostics for large perturbations from the present climate, in coupled models which employ flux adjustments. Published in Fanning and Weaver (1997c).
7. Analysis of decadal variability in the GFDL coupled model -- In progress
The ocean component of the GFDL coupled model was used to investigate whether or not earlier reported interdecadal variability was an ocean-only mode or a mode of the full coupled system. In particular, it was previously suggested that the variability in the full coupled model was either: 1) an ocean-only mode which was excited by atmospheric noise; 2) an internal ocean mode driven by fixed atmospheric fluxes which was made less regular through forcing from atmospheric noise; 3) a consequence of the use of flux adjustments. Through a series of experiments conducted under fixed flux boundary conditions we showed that none of these three hypotheses held and therefore concluded that the interdecadal variability found earlier was a mode of the full coupled system. Published in Weaver and Valcke (1998).
S. Zhang (Research Associate) also created a more efficient version of the GFDL coupled model in order to study low frequency variability using available computing resources. The increased efficiency was achieved by counting each atmospheric time step as being valid for six timesteps, thereby slowing down the synoptic scale motion. All of the basic physics in the original model was retained. This method used the fact that atmospheric response time is much shorter than that of the ocean. In addition, the climate memory of the coupled system is commonly believed to be resident in the ocean so the detailed history of atmospheric synoptic scale motion is not necessary. The atmosphere and ocean of this new version of the model are coupled monthly or roughly every slowed down synoptic cycle. Our results suggest that this method is an attractive alternative to other methods of achieving higher efficiency (such as poorer resolution and/or reduced physics). This model was then integrated many times for many hundreds of years to undertake a sensitivity analysis of the low frequency variability found in the coupled system.
El Niño/Southern Oscillation (ENSO) variability appeared in the model and is shown to be stronger when a lower vertical diffusivity is used in the ocean (reducing the tropical thermocline depth), or when the heat flux anomalies in atmosphere are reduced before passing them to the ocean (a method of reducing flux adjustments). Similar to the unmodified version of the GFDL model, interdecadal variability in North Atlantic was found, albeit slightly weaker. In addition, we found weak signals of a decadal oscillation in North Pacific with thermal anomalies rotating clockwise around the gyre, especially in those experiments which used a higher vertical diffusivity. The Pacific oscillation is supported by observational evidence and the results from the German (MPI) climate model. Currently being written up for publication.
8. Analysis of decadal variability in warmer and colder climates using the GFDL coupled model -- In progress
We have decided to approach this objective through the use of a hierarchy of models. To begin with a zonally-averaged atmospheric model is used which incorporates a parameterization of transient eddy activity. This model has been coupled by A. Brasket (a visiting PhD student) to an idealized Atlantic basin OGCM to investigate the influence of the atmospheric transports of heat and fresh water by transient storm activity on the strength and variability of the thermohaline circulation. We find that the strength of the thermohaline variability is determined by the dissipation rate of the ocean SST anomalies by the atmosphere. This has the interesting consequence of making the variability dependent on the mean state. Further work in this area will concentrate on ensuring that these results are general for the model and hold for a wide range of parameter space representative of the coupled climate system.
9. teleconnections in global OGCM-- In progress
Research into meeting this objective has recently begun. In the first phase we wished to examine the ocean response (and its internal teleconnections arising from NADW perturbations) to global warming radiative perturbations. As such, E. Wiebe (an MSc student nearing completion) is undertaking a sensitivity analysis using the coupled model to investigate the effect of various ocean mixing schemes on the ocean's response to global warming. His experiments have revealed the fascinating result (supported by recent observations) that there is a significant intrusion of warmed Atlantic water into the sub-surface Arctic Ocean during the initial response to the radiative forcing. In the southern hemisphere, we find that the particular mixing scheme used plays a significant role in the strength of the response of the sea surface temperature (SST).
10. simple models of decadal variability -- In progress
This objective is ongoing and initial analysis has been discussed under milestone 6. We are also attempting to develop a simple model for decadal variability in the Pacific. Since ENSO is a nonlinear coupled tropical atmosphere-ocean phenomenon, it is possible that decadal modulation of ENSO and its subsequent teleconnection to the North Pacific could explain the observed low frequency variability there. As pointed out by Gu and Philander a delayed negative feedback can be achieved through extratropical subduction of thermal anomalies (generated through the atmospheric teleconnection response to equatorial SST anomalies) which slowly propagate along isopycnals towards the equator where they reverse the sign of equatorial SSTs. We are in the process of developing a simple delayed oscillator model (involving the Battisti/Hirst model) to understand mechanisms for tropical/subtropical interactions and interdecadal variability. One of the parameters that is assumed to be constant in the Battisti and Hirst model is the pycnocline depth. By adding a meridional delay (through pycnocline subduction) to the equatorial pycnocline depth one can envision a mechanism for ENSO modulation.
11. project completion -- In progress
Publication of research results in the primary literature is ongoing. Below is a list of publications supported by the NSERC Strategic Grant to date.
Publications Supported by NSERC Strategic 1997-to date
1. Murdock TQ, Weaver AJ, Fanning AF, 1997: Paleoclimatic response of the closing of the Isthmus of Panama in a coupled ocean-atmosphere model. Geophys. Res. Let., 24, 253-256.
2. Weaver AJ, Eby M, 1997: On the numerical implementation of advection schemes for use in conjunction with various mixing parameterizations in the GFDL ocean model. J. Phys. Oceanogr., 27, 369-377.
3. Fanning AF, Weaver AJ, 1997a: Temporal-geographical meltwater influences on the North Atlantic conveyor: Implications for the Younger Dryas. Paleoceanogr., 12, 307-320.
4. Fanning AF, Weaver AJ, 1997b: A horizontal resolution and parameter sensitivity study of heat transport in an idealized coupled climate model. J. Climate, 10, 2469-2478.
5. Fanning AF, Weaver AJ, 1997c: On the role of flux adjustments in an idealized coupled model. Climate Dyn., 13, 691-701.
6. Fanning AF, Weaver AJ, 1998: Thermohaline variability: The effects of horizontal resolution and diffusion. J. Climate, 11, 709-715.
7. Weaver AJ, Valcke S, 1998. On the variability of the thermohaline circulation in the GFDL coupled model. J. Climate, 11, 759-767.
8. Giorgi F, Meehl GA, Kattenberg A, Grassl H, Mitchell JFB, Stouffer RJ, Tokioka T, Weaver AJ, Wigley TML, 1998: Simulation of regional climate change with global coupled climate models and regional modeling techniques. In: The Regional Impacts of Climate Change, An Assessment of Vulnerability. Watson RT, Zinyowera MC, Moss RH, Eds., Cambridge Univ. Press, pp. 427-437.
9. Weaver AJ, Green C, 1998: Global climate change: Lessons from the past -- policy for the future. Ocean Coast. Manag. in press.
10. Huck T, Colin de Verdière A, Weaver AJ, 1998a: Interdecadal variability of the thermohaline circulation in box-ocean models forced by fixed surface fluxes. J. Phys. Oceanogr., submitted.
11. Huck T, Weaver AJ, Colin de Verdière A, 1998b: The effect of different parameterizations and boundary conditions applied to the momentum equation in coarse-resolution thermohaline circulation models. J. Phys. Oceanogr., submitted.
12. Weaver AJ, Bitz CM, Fanning AF, Holland MM, 1998a: Thermohaline circulation: High latitude phenomena and the difference between the Pacific and Atlantic. Ann. Rev. Earth Planet. Sci., submitted.
13. Weaver AJ, Eby M, Fanning AF, Wiebe EC, 1998b: The climate of the last glacial maximum in a coupled ocean GCM/energy-moisture balance atmosphere model. Nature, in press.
14. Flato GM, Boer GJ, Lee WG, MacFarlane NA, Ramsden D, Reader MC, Weaver AJ, 1997. The Canadian Centre for Climate Modelling and Analysis global coupled model and its climate. in preparation..
7. Problems Encountered
No major problems have been encountered with respect to addressing the objectives of my proposal. In the first year of the grant, partner contributions were the same as in my original proposal with the exception of NOAA. I received $80,940 from NOAA in the first year (as opposed to my projected $41,100 contribution in the original proposal). I was also granted a one year no-cost extension to the project (ending Dec. 31, 1998). Unfortunately, the NOAA project in the oceans role in climate was not renewed for future funding. This was not due to a lack of progress but rather due to NOAA regulations regarding the funding of non US applicants. I was able to bring on a new US partner (Lawrence Livermore National Laboratories --LLNL) for this project and they have committed money ($29,610) and a substantial in-kind contribution in Year 3 (see section 8).
8. Partnerships and Collaboration
Funding from the Canadian Institute for Climate Studies (CICS) has been consistent throughout the project to date. In addition IBM Canada came on board my strategic project and contributed (via an international Shared University Research Grant) an IBM SP2 with 6 thin nodes and a high speed switch. This was the only award IBM International made in Canada and represents a donation of $565,895 (list price) or $339,537 (best customer 40% discounted price) worth of hardware. UVic has agreed to cover the IBM Consortium site license software charges and so I have not incurred any expenses in the acquisition of this machine. I have listed the in kind hardware contribution but not the university software contribution in the table above. I chose to do this as the university will also use the parallel software on their own machine and so it was not exclusively purchased for me.
My NSERC Strategic project has initiated many new collaborations as well as allowing me to build upon existing collaborations. I will outline these below under different partner headings.
LLNL: As mentioned earlier, a new collaboration (and partnership) has been set up with Dr. P Duffy and his team at LLNL. Dr. Duffy and his team have expertise in parallel computing and as part of our collaboration we have released our coupled model to them for parallelization. They in turn will be returning a parallel version of the coupled model. We shall use this parallel version of the model both locally and at LLNL to collaboratively investigate the effects of various parameterizations of convection and plume dynamics in the coupled system (milestone 5). In addition, we are going to examine the issue of detection and attribution concerning anthropogenic climate change. M. Eby (Research Associate) has already visited LLNL to initiate the model transfer, Dr. Duffy recently visited our group and will spend August 1998 working here, and I will be visiting LLNL in October 1998. This collaboration replaces the NOAA involvement as part of my Strategic initiative.
IBM: IBM Canada was keen to support my initial strategic application but the process took longer than anticipated. IBM Canada is a company that is committed to the environment and so was eager to fund my research. In addition, IBM will benefit from having our research group as one of the first to use their new parallel technology in climate modelling. They will provide personnel support (if needed) to assist us in the smooth transition towards the parallelization of our code. We will in turn make our code available to the international climate modelling community via the world wide web. Thus, by investing in the parallelization of our climate modelling code, IBM stands to take advantage of future business opportunities as other researchers who will use our code invest in parallel architecture. As detailed in the previous section, I was awarded an IBM SP2 with 6 thin nodes and a high speed switch in support of this strategic research. This machine is the same as that used by my partners at LLNL and the Canadian Centre for Climate Modelling and Analysis (CCCma).
CICS: CICS collaboration involves working together with other researchers (at McGill, Dalhousie, RPN, CCCma, UBC) towards improving our understanding of climate variability. In addition, collaboration with T. Murdock at CICS in the area of seasonal predictability is ongoing (for example, Murdock often undertakes experiments with CICS forecast tools on my computing facilities). Of central importance to CICS is the close collaboration between my group and the CCCma (CICS funds my research to improve their and the CCCma climate prediction capability).
CCCma: As detailed in section 10, the relationship between CCCma and my research group is unique and very stimulating. The CCCma has little internal expertise in ocean modelling/dynamics and this is one of the main reasons they relocated to Victoria from Toronto. Researchers in my group interact with CCCma researchers on a daily basis. My research group undertakes research into improving our understanding of the ocean and ice components of coupled models whereas their group focuses mainly on the atmosphere and ice components. G. Flato (their ice expert), my research associates (C. Bitz, M. Eby, M. Holland) and I meet regularly in an informal research discussion series. Researchers in the CCCma and I discuss ways of improving coupled models on a regular basis. The CCCma has provided me with computational resources when we undertake sensitivity analyses for them with our models. I provide library facilities for the CCCma. One of my students is also co-supervised by F. Zwiers (CCCma) and I am on the committee of one of J. Fyfe's (CCCma) graduate students. CCCma researchers conducted a course on numerical methods which was almost exclusively filled with my students.
Other: Extensive collaborations exist with researchers at the NOAA Geophysical Fluid Dynamics Laboratory at Princeton University as we move towards a further understanding of the variability in their coupled model. One of my past PhD students (Tertia Hughes) is now a Research Associate at Princeton University and also works closely with the GFDL team. In addition, our coupled atmosphere ocean model has been released and is now being used by researchers at: the University of Washington, University of East Anglia, University of Bremen, Pennsylvania State University, Seoul National University (as well as UBC and LLNL).
9. Training of Research Personnel
I am presently supervising 3 MSc, 4 PhD and 1 visiting PhD (Brasket from the University of Colorado) students. Daithi Stone, an MSc student, is jointly supervised by Francis Zwiers in the CCCma (one of my partners).
MSc Students Funding Source PhD Students Funding Source Edward Wiebe Strategic/UVic/CICS Olaf Dravnieks Strategic/CICS Pascale Poussart CSHD/FCAR Rebecca Sheltrum Strategic/CICS Daithi Stone Strategic/CCCma Masakazu Yoshimori CSHD Fiona McLaughlin DFO Education Leave Aaron Brasket Strategic/CICSThe NSERC Strategic grant (together with the partners) supported four students who have recently received their degrees. Trevor Murdock has taken up a position within CICS (a partner for this project) in the development of seasonal climate forecast products.
MSc (Year Granted) Present Affiliation PhD (Year Granted) Present Affiliation Daniel Robitaille Systems Analyst Univ. Augustus Fanning Assistant Professor (1997) Calif. Berkeley (1997) University of Victoria Trevor Murdock (1997) Technique Development Thierry Huck (1997) Research Associate CICS Univ. Calif. Santa CruzI currently supervise three research associates. Two others were supported through this project. Dr. Valcke, an NSERC PDF, took a tenured research scientist position in France and Dr. Zhang has relocated to BIO.
Postdoctoral/Research Funding Source Postdoctoral/Research Present Affiliation Associates -- Present Associates -- Past Michael Eby Strategic/CICS Sophie Valcke Research Scientist, CERFACS, Toulouse Marika Holland Strategic/CICS Sheng Zhang Research Associate, Bedford Inst. Oceanogr. Cecilia Bitz Strategic/CICS10. Accessibility of Results to Supporting Organizations
My four partners for this research are: CICS, CCCma, LLNL and IBM Canada. Each of these partners shares in the research objectives yet each of them is communicated and interacted with in different ways.
The CICS supports my research under two umbrellas. In the first, CICS provides partner funding to support my research into understanding climate variability. Communication with CICS takes many forms. I prepare semi-annual progress reports and attend semi-annual workshops on climate variability. Since the beginning of the Strategic project, workshops have been held in Victoria (March, 1997), Saskatoon (at the Canadian Meteorological and Oceanography Society (CMOS) congress, June 1997) and Montreal (February, 1998). In addition, a former MSc student (Trevor Murdock) is now working for CICS in developing improved seasonal forecast products and we communicate electronically on a weekly basis regarding developments in this area.
CICS funding under the second umbrella supports research into improving global ocean modelling. As such M. Eby, a research associate has developed and tested (through sensitivity analyses): a rotated grid capability for alleviating problems with convergence of meridians in the Arctic; a curvilinear coordinate option to allow for better treatment of coastlines; new advection algorithms to reduce numerical problems when centred differences are used; improved coupling techniques for dealing with air sea fluxes. He has also undertaken numerous sensitivity analyses to sub-grid-scale parameterizations. This technology is transferred to CICS by means of semi annual progress reports. Perhaps more important is the transfer of this technology to the CCCma as CICS ultimately is funding this research to improve the ocean component of the CCCma coupled model (see below). Finally, the progress of this component of the project was conveyed by me (in a talk entitled Global ocean modelling within the Canadian Climate Research Network) at the 31st CMOS Congress in a special CICS sponsored session.
While the communication with CICS is handled in a formal way, communication with CCCma is handled in a more informal way as the federal laboratory is located in the same hallway as my lab. Researchers in my group and the CCCma are in constant (daily) communication. Together we run a Topics in Atmosphere and Ocean (TAO) formal seminar series as well as an informal quasi biweekly research discussion series. In addition, Francis Zwiers and I co supervise a MSc student. The relationship between the CCCma and my group is very unique and is a most stimulating research environment to work in. Improvements to and new parameterizations for the ocean component of the CCCma coupled model are discussed with Drs. G. Flato and G. Boer informally. Those that are deemed to be of immediate applicability (such as the incorporation of improved sub grid scale mixing parameterizations) are incorporated. Those which require significant changes to the coupled model code (i.e., rotated grids; improved sea-ice models) are saved for discussion for future versions of the CCCma ocean model.
Communication with LLNL has now been formally established via a contract. P. Duffy will spend the month of August in Victoria and I will be visiting LLNL in the fall. We have transferred code between our labs electronically and no problems have arisen to date.
Communication with IBM Canada is achieved through periodic meetings with IBM representatives (specifically H. Leiserson and G. Schick. They have also asked that I periodically send them reprints and copies of my research progress reports. IBM has in turn written up a long description of my research in their IBM Visions magazine and periodically advertise the developments and advances we have made using IBM technology.
Finally, I was recently given the opportunity (at the invitation of NSERC) to address Members of Parliament in Ottawa (in the Parliamentary dining room) on the topic of: Global climate change: Science and Issues. A similar presentation was given before industry (oil, gas, forestry etc.) at the Canadian University Programme in Climate Change (CUPGC) inaugural workshop recently.
11. Potential Benefits
The research supported by my strategic project has immediate benefits to society through an understanding of climate and climate change/variability and the processes involved in it. For example, Canada has recently made commitments under the Kyoto Accord to reduce greenhouse gas emissions. It is only through continued research that we will understand what effects these (and other nations') greenhouse gas reductions will have. I am in communication with a number of oil and gas companies in Alberta (through my role as lead scientist on the steering committee of CUPGC) regarding the means by which they will attain Canada's committed reduction and whether or not these are realizable. I also participate in international efforts (including the United Nations Intergovernmental Panel on Climate Change) at summarizing our present knowledge of these issues for policy makers. My strategic project does not only entail research into global climate change but also into the investigation of predictability of climate on the decadal timescale. Large-scale climatic features (such as ENSO and the NAO) cause significant effects on climate variability in Canada. Understanding their predictability on decadal timescale is of utmost societal importance. T. Murdock is now working in CICS to convert basic research into improved seasonal climate forecasts.
The training of highly qualified personnel through this CFI initiative will provide for a new generation of educated young Canadians in the area of climate science. Many Canadian industries (e.g., oil and gas, forestry) are looking to hire bright young climate scientists. Unfortunately we are unable to meet the growing demand. Canadian industry are also demanding that the Canadian government make informed policy decisions regarding climate mitigation strategies based on Canadian based science. They are eager to participate in a process that ensures that this is accomplished (including their strong endorsement of CUPGC) as they stand to suffer enormous economic costs in attempts to meet mandatory emission reductions (for example). The research conducted by my group is therefore key to reducing the uncertainty and increasing the predictability of climate and climate change and hence benefit Canadian industry through their ability to make more informed decisions regarding climate mitigation and adaptation strategies.
Finally, I am committed to educating the public regarding issues concerning climate and climate variability. I am constantly approached by the national (and international) media and believe it is important to convey my research to them in an attempt to educate the public so that they understand the issues that we as a global society are facing.