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Climate Change and the Loss of Sea Ice in the Canadian Arctic

69.0N 120.4W

June 24th, 2013 Category: Climate Change MODISTerra

Canada – June 22nd, 2013

Climate change affects every part of the world in a different way, but most experts agree the North will be impacted more than any other region. Sea ice spans most of the Arctic’s coastal and inter-island channels from eight to 12 months of the year and supports a number of species. It’s expected to undergo the most significant transformation.

The effects of climate change in the North are not new occurrences. Actually, changes have been happening for quite some time. Over the past 25 years, Inuit and scientists have observed a decrease of roughly seven percent in sea ice area, with the largest rate of decrease during the summer months.

Using highly scientific models of prediction, it has been determined that if warming trends continue at their current rate, by the end of this century the Arctic Ocean will be nearly ice-free during the summer.

If Arctic sea ice melted away, large sections of the Arctic Archipelago would open up. This would create more noise, traffic, pollution and safety issues for both humans and wildlife. Because of increased noise, traffic and pollution, marine ecosystems would be disturbed. Sea ice is a major control on the interactions between marine and terrestrial ecosystems.

The undersurface of sea ice is a growth site for algae and invertebrates that sustain the food web (a food source for many types of fish). If sea ice melted away there would be a decrease in amounts of sub-ice phytoplankton, a key source of food for copepods and fish. The fish that depend on phytoplankton for food are a main source of nutrition for narwhals, beluga whales and seals. Polar bears depend on seals for food. Because of sea-ice depletion and a decrease in marine food, seal populations would drop, having a direct impact on polar bears.

Human beings are ultimately being affected by a decrease of sea ice in many ways. Northern communities have reported changes in the physical environment over the last 20 to 30 years. They have not been able to hunt as much because of a lack of traditional food species such as fish, seals and whales. Hunters depend on these species not only for food but also for money, as they can sell tusks or furs. In addition, a warmer climate could cause difficulty in conserving perishable food through cold-storage or natural freezing. Should sea ice thaw and the Arctic Archipelago open up there would be safety issues because the area would be more prone to landslides, floods and overall lack of coastal stability (click here for more information).

Arctic Ice by Canada and Greenland

80.8N 71.4W

June 24th, 2013 Category: Climate Change MODISTerra

Canada and Greenland – June 22nd, 2013

This image shows glacial ice and sea ice in the Arctic, between Canada and Greenland. Effects of Arctic climate change include a marked decrease in Arctic sea ice; thawing permafrost, leading to the release of methane, a potent greenhouse gas; the release of methane from clathrates, leading to longer time-scale methane release; the observed increase in melt on the Greenland Ice Sheet in recent years; and potential changes in patterns of ocean circulation.

Scientists worry that some of these effects may cause positive feedbacks which could accelerate the rate of global warming. The sea ice in the Arctic region is in itself important in maintaining global climate due to its albedo (reflectivity). Melting of this sea ice will therefore exacerbate global warming due to positive feedback effects, where warming creates more warming by increased solar absorption.

Arctic Sea Ice by Russia and Climate Change Issues

69.8N 163.3E

June 18th, 2013 Category: Climate Change MODISTerra

Russia – June 18th, 2013

Since 1979 the Arctic region has been extensively monitored by satellites. They detect the ice surface area, the extent of the area covered with ice and also the total amount or volume of ice. The results of these observations are startling. For example, sea ice area and the amount of perennial (multi-year) ice has decreased dramatically over the past 3 decades. In 2012, the September average ice extent dipped below 4 million km², which is about half of what it was in 1979. Ice volume shows a comparable rapid decrease (click here for more information).

Russian Shores and Rapid Melting of Arctic Sea Ice

69.3N 161.2E

June 16th, 2013 Category: Climate Change MODISAqua

Russia – June 15th, 2013

Strong warming in the northern high latitudes is causing Arctic sea ice to rapidly melt. It’s one of several changes in the Arctic region, including increased melting of the Greenland ice sheet and permafrost in northern Russia and Alaska, which pose serious risks for the world as a whole. This image focuses on ice along the northern shores of Russia.

The area and thickness of Arctic sea ice fluctuates from year to year, and is affected by weather patterns, ocean circulation and other natural influences. However, the ice on the surface of the Arctic Ocean has been diminishing for the past 30 years, in both area and thickness. Over the past 10 to 15 years, it has begun to disappear faster. Recently, it has fallen to a record low (the previous record being in September 2007). Since 1980, the ice has roughly halved in area, and the volume of ice has dropped to just a quarter of what it was.

White ice reflects much more sunlight back to space than does ocean water, which absorbs incoming sunlight readily. As the area of sea ice decreases and the area of exposed ocean water increases, more sunlight is absorbed, heating the surface of the water and the atmosphere above it. This strengthens the Arctic region warming trend – average temperatures of the high northern latitudes are rising at double the global average temperature increase.

The Arctic sea ice is declining much more quickly than scientists expected only a decade ago. It is very likely that, with the continued decline in sea ice that has occurred over several decades, we’ve already crossed the point of no return and that we’ll have an ice-free Arctic Ocean during summer at some point in the near future. Scientists now consider this could happen by 2030 or even earlier (click here for more information).

Global Warming and Sea Ice by Northern Canada

69.9N 120.1W

June 13th, 2013 Category: Climate Change MODISTerra

Canada – June 12th, 2013

Bodies of water in the Arctic, in Canada’s Northwest Territories and the province of Nunavut are covered in ice: the Great Bear Lake (below), Amundsen Gulf (upper left) and Queen Maud Gulf (upper right). Most of the sea ice breaks up in July during a normal year, with some areas only breaking up in August. Here, ice can be seen breaking up in Amundsen Gulf, near the left edge.

Ongoing changes in the climate of the Arctic include rising temperatures, loss of sea ice, and melting of the Greenland ice sheet. The Arctic ocean will likely be free of summer sea ice before the year 2100. Because of the amplified response of the Arctic to global warming, it is often seen as a high-sensitivity indicator of climate change.