Context
Earth’s climate is changing rapidly, with the global temperature now rising at a rate unprecedented in modern history. These climate changes are being experienced particularly intensively in the Arctic. Arctic average temperature has risen at almost twice the rate as in the rest of the world in the past few decades (ACIA 2004). Arctic climate changes are expected to exert a strong impact on northern ecosystems and communities. The study of climate change dynamics of the Arctic is thus very important for the understanding of global climate because the Arctic plays a key role in global climate change dynamics.
In order to effectively address the highly complex Arctic climate and environmental science questions of the 21st century, scientists, resource managers, decision makers, and interested citizens will need access to more detailed information of the Arctic and its role within the global climate system. Comparison of past and present climate variability will give policy makers a tool to justify laws for the reduction of greenhouse gases inspired by the Kyoto Protocol.
Predictions of the extent and impact of future climate change depend on our ability to reliably model past climatic regimes. Of particular significance is determining when, where, and how rapidly climate has varied during the Pleistocene and Holocene, when boundary conditions were similar to today. The need for high-resolution paleo-records is especially pressing for high latitude regions given that they are now subject to increasing physical perturbation caused by anthropogenic changes in the Earth’s atmosphere in combination with cyclic forcing. Until now the only terrestrial climate record of the arctic which covers several interglacials is the impact crater lake El’gygtgyn in Sibiria. The Pingualuit impact crater lake (also known as the New Québec crater lake) is one of the rare terrestrial sites in high latitude regions that has stored the climate history of the Canadian Arctic over the past 1.3 million years. The Pingualuit crater lake therefore offers the unique research opportunity to obtain paleo-records from the Canadian Arctic that extend back hundreds of thousands of years.
Accurate climate models are essential for improved weather forecasting and prediction of environmental change. The latter is especially important for federal policy and management decisions. Yet one of the central findings of the Arctic Climate Impact Assessment (ACIA) report as presented in Reykjavik in 2004 was that climate data sets for the circumpolar region are currently inadequate to constrain and validate regional-scale models. The northern Québec region is especially important in this regard given the major economic importance of its hydroelectric power industry, and the prospect of increased coastal shipping with reduced sea ice duration. Furthermore, the available data suggest that northern Québec shows atypical stability in its climate relative to equivalent latitudes elsewhere, thus making this region the ultimate bellwether of continental and global change. The research at The Pingualuit crater lake addresses this need for regional data by providing an unprecedented temporal record of paleoclimate history for northeastern North America.
Objectives
The primary objectives of the CFCAS-funded research are:
– to reconstruct and investigate the long term climate, hydroclimate and ecological records for the eastern Canadian Arctic through a coordinated analysis of complementary high-resolution proxy records
– to develop climate scenarios that will help predict the ecological consequences of global change
– to determine and understand their global influences and consequences for Arctic climate feedbacks and decadal-scale climate variations. These results will be used to assess the probability of abrupt climate changes on decadal time scales in the past and in the future.
Outputs
The research will improve our understanding of climate-ecosystem interactions in the North and of the “response” of the countless freshwater lakes and ponds in northern landscapes to global climate change. For example, the predicted climate-induced shifts in northern tree-line and increases in thermokarst activity in permafrost regions (IPCC Report 2001) are likely to have strong impacts on the physical, chemical and biological conditions of these freshwater ecosystems, ultimately leading to the disruption of the dynamics of primary production and the community structure of food webs.
Given the need for well-dated terrestrial paleoclimate records that have sufficient time resolution to characterize natural climatic variability at a regional geographic scale in remote northern regions (ACIA 2004), we anticipate that the novel paleo-data generated through our project will contribute significant insight to the paleoclimate history of north-eastern North America and Earth’s high latitude climate dynamics. Aeolian inputs will allow to infer paleo winds, whereas the terrestrial climate records will complement information from ice cores and marine sediments. Through our proposed interdisciplinary research approach, hypotheses regarding forcing mechanisms and climate cycles can be tested. Furthermore, inter-regional comparisons of decadal to century-scale paleo-records can be used to determine if shifts in the climate system are coincident and manifested as changes in the same direction and magnitude. The climate record of the Pingualuit crater lake will help to understand key climate systems and atmospheric land-sea interactions. This information will be relevant to climate modelers and researchers from within the Canadian and international paleoclimatology and paleoecology communities as it gives high priority to science goals of international arctic climate research programs (e.g., PARCS program, 2002).