The Arctic region, with its vast landscapes of ice and unique ecosystems, is undergoing significant changes due to climate change. U of M research associate at the Centre for Earth Observation Science Alex Crawford’s research explores the Arctic climate system and how it is affected by climate change.
Crawford’s journey into climate science began during his undergraduate years, when a research opportunity involving sediment from the bottom of the ocean near Antarctica ignited his interest. This experience laid the foundation for his exploration of climate change, leading him to pursue graduate studies with a focus on Arctic climate science.
One of his primary research areas is the study of Arctic sea ice. Using large climate models, Crawford analyzes historical variations in sea ice cover to make projections for the future. Currently, his work involves examining polar bear and seal habitats in Hudson Bay, considering factors such as the duration of sea ice cover.
Another area of focus for Crawford involves Arctic storm systems.
“A lot of my work has been better understanding how these systems develop, how they interact with the surface,” he said. “That includes the sea ice, but also how they interact with land, ocean, vegetation [and] the animals on the surface.”
Crawford emphasized the accelerated rate of warming in the Arctic compared to the global average. The loss of sea ice, a consequence of rising temperatures, significantly influences the region’s ecology.
In the northern regions of Manitoba, Northwest Territories and Nunavut, residents are grappling with the consequences of thawing permafrost. Permafrost, a layer of permanently frozen ground, is transitioning from a stable landscape to a more dynamic, mobile environment that expands and contracts as it thaws and refreezes. This thawing during summer and freezing during winter poses challenges for infrastructure development, such as airports, railroads, roads and pipelines.
Crawford noted that unlike Winnipeg, where road systems need frequent renovations due to the impact of freezing and thawing land, places like Northwest Territories or Nunavut have not had to deal with this concern until the onset of thawing in recent times.
Climate change in the Arctic region is also significantly altering the habitats of polar bears, seals and other marine mammals.
Crawford explained that even microscopic organisms like phytoplankton are affected by this environmental shift. These single-celled organisms similar to plants play a crucial role in the ecosystem. They require sunlight to generate essential sugars and cell structures for survival.
With the diminishing sea ice and snow cover in the Arctic Ocean, more sunlight penetrates the water than in the past. Consequently, this alters the timing of phytoplankton blooms. The change in when these blooms occur disrupts the seasonal cycles of other Arctic species that rely on this schedule. This disturbance at the base of the food web can have far-reaching consequences, influencing various aspects of the Arctic ecosystem.
In Hudson Bay, a focal point of Crawford’s recent research, sea ice projections are critical for understanding the future of polar bear populations and the local tourism industry. While climate models initially suggested a biased outlook, Crawford’s research — incorporating observations and satellite data — provides a more optimistic perspective. However, challenges remain, especially concerning the reproduction and survival of polar bears.
“Right now, the state of the sea ice in Hudson Bay is already impacting the recruitment rates of polar bears in and around Churchill,” he said. “They’re already seeing declines.”
When considering the broader implications of Arctic climate change on the global climate system, Crawford explained the complex interplay between Arctic warming and tropical climate changes. The potential weakening of the polar jet stream, a key component of mid-latitude weather patterns, could result in more erratic weather conditions in regions like Winnipeg.
Crawford highlighted how the Arctic and the rest of the world are deeply interconnected, emphasizing the need for collective action to address climate change. While Crawford encourages individuals to be aware of their own environmental impacts, he stressed the need to advocate for policies that address the broader implications of climate change.
“In the end, it’s only collective action that can really do it, not just your individual decisions,” he said. “You’ve got to put pressure on your elected officials to make decisions that will both help mitigate how much climate change there is and help us adapt to the changes we’ve already committed to.”