This research is aimed at documenting the timing, mechanisms, and effects of climate changes past and present on the Cumberland Penninsula of Baffin Island. Arctic regions are particularly sensitive to shifts in climate, and the resultant changes in ice cover initiate positive feedback mechanisms that affect global climate systems. As such, understanding how this region has responded to climate forcings throughout the Holocene will help us better constrain its role in future climate change and contextualize the magnitude of current warming.
To document past climate and environmental changes, we are employing a number of methods:
- Dead vegetation dating: By collecting dead tundra vegetation that recently emerged from receding ice caps and radiocarbon dating that vegetation, we can get an idea of when that location was last ice-free and when snowline lowering due to cooling summers resulted in widespread vegetation kills. This is an important record to obtain right now, as each summer local ice caps are receding further and the ancient vegetation entombed beneath them--along with the invaluable records they contain--are being removed by wind. For an idea of what these records can tell us, see this page on the cause and onset of the Little Ice Age.
- Cosmogenic exposure dating: We will collect rock samples from glacial moraines and from the margins of ice caps and use cosmogenic exposure dating to determine when those rocks were deposited. This helps us constrain when glaciers were at their maximum extent at various times in the past.
- Lake coring: We also plan to collect sediment cores from two glacial lakes. Lake sediments act as archives of past environmental change and are particularly useful in tracking changes in glacial activity, as glacial advances are typically accompanied by characteristic sedimentation in lakes. Various other geochemical and biological proxies contained in the sediment can tell stories about past climate and ecological change as well. Lake cores complement our other methods because they provide a continuous record over the period of deposition, whereas the two dating methods above give us a snapshot of one particular time in the past.
To see what it's like to research climate change, including braving polar bears and arctic storms while commuting to work by helicopter and canoe, read blog posts by
- Simon Pendleton's post from Baffin Island on the Traveling Geologist (8 April 2016) and
- Sarah Crump's blog post from Baffin Island on the WiSE Lab and Field Blog (1 October 2015)