Description

Objectives (international and national)
The CSHD Program is a Canadian contribution towards the objectives of the IGBP (International Geosphere Biosphere Program), PAGES (PAst Global ChangES) and GAIM (Global Analysis, Integration and Modelling) core projects which are focused on paleoclimatic reconstructions and modelling, respectively.

The goal of the PAGES project is to explore the implications of the record of past climate changes as these are revealed in a variety of paleoclimatic proxy records including ice cores, lake cores, deep sea sedimentary cores, tree rings, loess deposits, etc. PAGES research is designed to elucidate the interactions between the distinct components of the climate system revealed in these proxy records in order to understand how they have controlled the evolution of past climate. Recently, PAGES and the Scientific Committee on Ocean Research (SCOR), recognizing the unique problems associated with addressing the marine aspects of the climate system, have sanctioned a new program IMAGES to serve as the marine component of PAGES.

The main goal of the GAIM project is the construction of models of climate system behavior on all time scales with a special concentration on the physics of the carbon cycle. In pursuit of this goal the project also comprises distinct analysis and interpretation components both of which, together with the modelling activity, are to be pursued on a global scale. Modelling will be pursued with both coupled atmosphere-ocean general circulation models (which include chemistry and terrestrial biosphere components -- AOGCM's) as well as reduced models that may be integrated over longer time scales than those possible with the AOGCM's.

The goal of the Canadian CSHD program is to develop a national capability in paleoclimate modelling in which both General Circulation and reduced system models of the climate system may be tested against records of past climate change so as to improve the parameterization schemes on which such models are based.

To meet this goal CSHD researchers must first compile and carefully analyze the paleoenvironmental indicators needed to construct accurate maps of surface conditions over the Canadian and adjacent North American continent, including proximate oceans, that are required to verify or refute the predictions of climate state delivered by general circulation models. This will lead to the production of a National Paleoclimatic Atlas.

Simultaneously, CSHD researchers will be developing the subsystem and reduced system models that are required to understand the evolution of the climate system over the 100,000 year time–scale of a single glacial cycle and to develop the data sets that are required to test these models.

The CSHD research program involves a number of carefully staged elements that begin with investigation of climate states in the most recent past and then extend further back in time. By choosing appropriate time slices for analysis we will be able to isolate individual contributions to climate change and thus test the various components of the general circulation model. There are six components to the research plan:

1. Climate and Environment at 6 kyr BP — deglaciation complete – surface topography and sea surface temperatures similar to today, but insolation substantially different.
2. Climate and Environment at 21 kyr BP — Last Glacial Maximum.
3. Climate and Environment at Last Interglacial — 125,000 kyr BP.
4. Physics of the Late Quaternary Glacial Cycle.
5. Proxy Records — applied to all projects.
6. Geochronology and Correlation — applied to all projects.

In fulfilling these objectives, Canadians will be addressing the goals of PAGES and GAIM in a single national effort. We see great merit in this approach as it takes advantage of existing Canadian expertise in several traditionally disparate fields and forces the linkages and focus that will be necessary if we are to rapidly advance the state of our understanding of the climate system. The need for these linkages has been recognized by the international Paleoclimate Modelling Intercomparison Project (PMIP) and the Canadian CSHD program will serve as an example for the international community. In addition, the objectives of the CSHD Program directly address the goals of the Atmospheric Environment Service's (AES) initiative to devote Green Plan funding to the development of a Climate Research Network for Canada.

Number of studies, P.I.'s, etc.
The scientific core of the CSHD Program is comprised of the contributions of 10 Principal Investigators, each who may by associated with co-investigators. These contributions represent distinct work in the areas of paleoclimate system modelling and paleoclimate proxy record compilation and interpretation. These distinct elements, however, have been assembled so as to constitute in their collectivity and mutual interdependence, a coherent, and we believe, imaginative response to the international goals of both PAGES and GAIM as well as to the national goals of the AES's Climate Research Network. Figure 1 illustrates the linkages and interdependencies of the CSHD Program elements.

Status
Proposal submitted to AES and NSERC Collaborative Special Projects: Nov. 1993.
Funding Approved: Nov. 1994.
Receipt of Funding by Project Scientists: Feb-Apr. 1995.
First Meeting of Scientific Steering Committee: April 22-23, 1995.

Figure 1: Linkages amongst CSHD program elements.

Linkages
As discussed above, CSHD is a direct Canadian contribution to the closely linked IGBP core projects PAGES and GAIM. The Canadian effort is well situated to integrate into these international efforts as CSHD P.I. W.R. Peltier is a member of the Scientific Steering Committees of both PAGES and GAIM as well as a member of the Scientific Steering Committee of IGBP as a whole. N. Rutter, Chair of the CSHD management committee has also been on the Scientific Steering Committee of PAGES and T. Pedersen has just been appointed to it. L. Mayer is currently on the Scientific Steering Committee of IMAGES.

On a national level, the CSHD Program is part of the Canadian network on climate modelling that is being developed by the AES and is part of the Canadian Global Change Program (CGCP) of the Royal Society of Canada which is partially funded by Environment Canada. W.R. Peltier is a member of the Board of Directors of the CGCP which will facilitate the transfer of information to this national steering group. While the CSHD has developed within the international context of IGBP it is also a response to the important stimulus to climate system research that has been provided by the National Green Plan. As a component of the Green Plan, AES made a commitment to establish a Climate Research Network. It was the AES's recognition of the importance of paleoclimate research within this network that provided the first opportunity for CSHD investigators to come together and begin to develop the plan that eventually led to the CSHD Program.

Management Structure

Figure 2: CSHD Management Structure

International Advisory Board: Five voting members and one representative each from NSERC and AES. Objective assessment of research – reallocation of resources if necessary. P.I. and Exec. Director – ex-officio. Meet at least once per year.

Executive Committee: One representative each from GCM, reduced models, terrestrial and marine projects plus program P.I. Responsible for overall management of program and implementing decisions of resource allocation that may flow from International Advisory Board. Oversee Secretariat and prepare annual report.

Scientific Steering Committee: Committee of the Whole consisting of each P.I. of the program. Responsibility is to assure high level of integration amongst different program elements. Will meet twice per year.

CSHD Secretariat: Executive Director and part-time Secretary. Responsible for organizing committee meetings, financial reporting, writing articles on CSHD for various newsletters and for being the day-to-day point of contact for members of the program.

Funding

	1995	1996	1997
NSERC	$685,000	$700,000	$655,000
AES	$300,00	$200,000	$200,000
NSERC Ship time	$250,000

Difficulties and Challenges
The program has really just begun and thus difficulties in execution have not yet been encountered. Planning difficulties have been minimal but revolved around assuring communications amongst proponents and that a focused, integrated program would evolve. The management structure went through several iterations with the funding agencies but a mutually agreeable structure was arrived at with little difficulty.

Projected Findings
The CSHD Program will produce a Canadian capability in paleoclimate modelling using the AES AGCM, a coupled AOGCM that will be developed, as well as reduced models that will enable modelling of climate over the longer timescales associated with glacial cycles. In order to test and verify these models a data base of paleoclimate indicators for North America and adjacent oceans will be compiled and analyzed, leading to the production of a National Paleoclimatic Atlas for Canada. Along with this data base, other intermediate products will be the improved parameterization of physical processes (e.g. cloud microphysics, deep water formation processes, etc.) in order to reduce the uncertainties in climate model predictions. With reduced uncertainties (demonstrated by the ability to accurately recreate past and present climatic states), the models can be used to make future predictions.

Impact on Canadian Science
The essence of the CSHD program is the development of a focused Canadian effort devoted to the application of the Canadian Climate Center GCM (and eventually an AOGCM) in the simulation of past climates, leading to a verifiable predictive capability. The drawing together of ten distinct research groups into an integrated and focused effort aimed at an important scientific (and societal) issue is, in itself, a boon to Canadian science. Because the main data sets that will be employed concern climate variations through an ice age cycle and because this global cycle has its most profound expression on the Canadian land mass, the Canadian Paleoclimatic Atlas will be a critically important national asset as well as a unique contribution to ongoing international global change efforts. Finally, the CSHD program will contribute to the training of the next generation of theoretical environmental scientists in the application of mathematical methods for environmental simulation as well as the next generation of field-oriented researchers in the latest techniques of multi-proxy environmental reconstruction.

Impact on Policy Making
There is increasing public awareness of the need to reduce the uncertainties concerning ongoing changes to the global environment particularly the need for more accurate predictions of the consequences of anthropogenically induced changes. With the increasing (population related) stress on the environment that is expected in the coming decades, policy makers will be increasingly reliant upon predictions of large-scale climate models (AOGCM's) for reliable estimates of future environmental scenarios. This research program is aimed at producing more accurate and reliable Canadian climate models.

Future Plans
The program has only just begun, but future efforts will inevitably be aimed at improving the capability of both the AOGCM's and the reduced system models. The key will be to achieve more speed and accuracy in the simulation of past and present climate states and thus, more confidence in the ability to predict future climatic conditions.