Panel IIIA: Climate History and International Environmental Agreements
Monday, March 16, 2020; 15:45-16:45
Room MB 9B, 9th floor of the John Molson Building (MB) at 1450 Ave. Guy
Fire is an important aspect of ecosystems and a hazard for humans. In forest ecosystems, fire has a role in determining species composition of both flora and fauna. Understanding the characteristic fire regime can allow us to more fully understand the ecosystem as a whole and dynamics between various long scale processes, including nutrient cycling, biodiversity maintenance and habitat structure. I am analyzing a lake sediment core taken from Étang Fer-de-Lance in Mont Orford Park in order to understand the fire regime on a long time scale at this location. I took contiguous 1 cm samples along the depth of the core, which reaches to 232 cm below the sediment water interface. Using carbon dating, the oldest section in the core can be dated back 2000 years. I extracted charcoal particles from each sediment sample and then analyzed the surface area of charcoal contained in each sample using image analysis software called Winseedle. This analysis of the charcoal surface area from the core shows a marked in change in fire regime following European settlement in the area. Historically, European settlement had an immense influence on ecosystems, including fire patterns and regimes. In North America, Europeans’ arrival corresponded with an immense increase in forest clearance for farmland, timber and settlements relative to the effects of Indigenous peoples. Fires became more frequent following expansion of European settlement and railroads. Finally, more dense and widespread settlement led to a large emphasis on fire suppression. The charcoal record from Étang Fer-de-Lance follows this pattern: a large initial charcoal peak around 1600 AD from fires set for European land clearance, a series of lesser successive peaks from further clearance and then relative fire suppression starting at 1850 AD. By further comprehending the characteristic fire regime of the Mont Orford region, it becomes possible to more deeply understand long-term dynamics of this overall forest ecosystem. This study will be combined with pollen analysis of the same core from Claire O’Neill Sanger to provide a more descriptive picture of the forest ecosystem at the study site.
Long-term climate records are necessary for establishing reference conditions for ecosystem-based management and climate monitoring. In Canada, human recorded instrumental records of climate only span at most 200 years. Hence, to detect local environmental change due to global warming, we need longer-term environmental records in order to properly understand if recent changes are outside of the normal range of variability, or rather within the natural low-frequency variability of a region. Here in Quebec, numerous studies have used the paleoclimate-proxy of pollen extracted from lake mud to reconstruct forest dynamics and infer climate variability throughout the Holocene. However, in southeastern Quebec, high-resolution pollen records are lacking to more precisely assess centennial-scale climate variability over the past two millennia.
In order to fill this paleo-environmental record gap and investigate forest-climate interactions at the centennial-scale over the past 2000 years, our research analyzes pollen from a sediment core taken from Étang Fer-de-Lance in Mont-Orford National Park. Sampled a resolution of approximately 10 years, the pollen record permits the reconstruction of domain boundary changes within the sugar-maple-hardwood forest subzone, as well as, land use changes due to European colonization of the Eastern Townships region.
Our lake sediment core is 2.3 m long. Seeds and other organic macro-fossils found throughout the sediment cores were extracted and dated using 14C and 210Pb dating methods, as well as the Ambrosia rise, to establish the chronology of the core which spans from 320 BC - AD 2018. Loss-on-ignition analysis was performed to estimate the organic and carbonate content of the sediment. Pollen samples were isolated from the sediment using a sieving process and acetolysis wash procedure and mounted onto slides for microscopy. Our reconstruction shows a regrowth of the eastern deciduous forest following settlement in the region, as well as, a continuing decline in the eastern hemlock and beech forest since the Little Ice Age (AD 1450-1850). This study contributes to our understanding of the natural low-frequency forest dynamics of southeastern Québec.
A long record of a region’s climate is an important resource to understand an environment. It allows us to give context to climate change, distinguishing human-induced climate change from natural variability and is an important resource for the conservation of vulnerable plant and animal species. The Chic-Choc and McGerrigle Mountains that form the interior of the Gaspésie peninsula are among the highest peaks in the province of Québec and such mountainous regions are known to be sensitive early responders to climate change. The region has a unique ecosystem home to vulnerable wildlife: the river valleys are important Atlantic salmon spawning grounds and the summits are refuge for rare plant species and the last population of caribou remaining south of the Saint-Lawrence river. The mountains of the Gaspésie have relatively short weather records, beginning only after 1950, a timespan too brief to provide a robust understanding of climate in this region.
Short climate records can be supplemented at an annual resolution by studying the width and composition of tree rings. In seasonal climates, trees grow a distinct ring of wood every year that can hold valuable information about the surrounding environmental conditions. In this region, many areas with old trees have been protected as part of the Parc national de la Gaspésie, conserving several hundred years of natural climate records. In collaboration with the park, we have sampled hundreds of conifers, including eastern white cedars (Thuja occidentalis), black spruce (Picea mariana), white spruce (Picea glauca) and balsam firs (Abbies balsamea) in variety of locations from riverside cliffs to harsh mountaintops. The ancient trees of the region have allowed us to make a chronology of tree rings dating back to 1561 AD and we have mapped many of the oldest trees in the park. Collectively, these trees show a common pattern that has allowed us to develop a reconstruction of regional water availability that extends over 200 years into the past. Some sites also have potential for us to understand other aspects of climate like the past temperature and snowpack.
This paper examines the effect of including trade sanctions into environmental agreements on the level of participation and the gains of cooperation. The paper builds on the non-cooperative game approach of the IEAs literature extending the basic model by introducing firms that trade in a global market. Countries choose emission taxes and tariffs either unilaterally or collectively through a formal joint agreement. Signatories to the agreement enjoy tariff-free trade among themselves while they choose an emission tax that maximizes their aggregate welfare. Nonsignatories pay a tariff on their exports to signatories, choose a tariff to levy on their imports and an emission tax taking into account only the effect of their emission on their own welfare. Resorting to numerical simulations, the paper shows that participation to the joint agreement is high: approximately 70% of countries join the joint agreement. This is not only a much larger coalition than the one that the standard IEA literature predicts, but it also achieves substantial improvements in welfare. The paper present some numerical simulations using different parameter values confirming that these results are not sensitive to the parameter values.
This event is brought to you by the Loyola College for Diversity and Sustainability and the Loyola Sustainability Research Centre with the support of the Office of the Vice-President, Research and Graduate Studies; the Faculty of Arts and Science; the Canada Excellence Research Chair in Smart, Sustainable and Resilient Communities and Cities; the John Molson School of Business; and the Departments of Biology; Communication Studies; Economics; Geography, Planning and Environment; Management; and Political Science at Concordia University.