The Arctic Sea Ice

Melting of sea ice due to temperature rise in the Arctic Ocean results in reduced sea ice due to which the Arctic is warming four times faster than the rest of the globe. Reduced sea ice is one of the main drivers for Arctic amplification. Hotspots in the Bering sea are warming seven times faster than the rest of the Arctic.

Sea ice is a thin layer of seawater that partially melts in the summer and freezes in the cold winter. During snow precipitation, sea ice is covered by snow which reflects 85% of incoming sunlight back to the atmosphere and hence increases the albedo effects.

As sea ice and snow melts during high temperature in Arctic summers results in decreased coverage of ice and snow, the Arctic Ocean exposed to sunlight, The Arctic Ocean with more open water will absorb more incoming solar radiation instead of reflecting it as an open ocean with a natural dark surface absorbs 90% of sunlight. As a result of that the albedo effect decreases. Reduced sea ice or more open ocean water lead to more and more sunlight to be trapped within the Arctic Ocean, further contributing to the ocean warming and amplifying sea ice melt. This creates a feedback loop or cycle which contributes to climate change.

Sea ice melts----->reduced sea ice—->ocean with more open water—> more heat absorption—-> heating of ocean water------> further acceleration of sea ice melting —-->vicious cycle------>contributing to climate change.

Sea ice in the Arctic keeps the temperature of the polar regions cool and has an important albedo effect on the climate. The bright shiny surface of sea ice in the Arctic reflects the sunlight but the Arctic Ocean with dark surface exposed to sunlight as sea ice disappears, absorbs more sunlight and heats up, this increases the total heat content in the ocean and helps to further melting of sea ice and also delays the recovery of ice during the polar night. The effect of Arctic sea ice loss on global warming will be greater in future as more sea ice is lost.

Heat waves in the far North have driven the wildfires and ice melt in the Arctic region including Alaska, Greenland, Siberia, Canada, Scandinavia.

The amount of air pollution coming from Europe also contribute to.

Ice-free summers in the Arctic Ocean will result in economic implications as it will open up more shipping routes, more fishing grounds which in turn put a heavy pressure on the already threatened ecosystem of the Arctic. The Arctic warming and reduced sea ice will significantly increase traffic through the Arctic Ocean and will drop traffic in the Suez canal as a result of greater shift in trade flows between Europe and Asia, diversion of trade within Europe.

Impacts of Sea Ice Melting

1. Melting ice in the Arctic region streams into the ocean and sea causing sea level to rise. This leads to devastating floods on the coastal areas across the world. 

2. Sea ice melting resulting in addition of freshwater into oceans leads to shifting of weather patterns across the U.S. and Europe (as ocean currents are disrupting) and also migrates many marine species between tropics and Arctic each year.

3. Sea ice declined in extent due to rapid Arctic warming, putting ice-dependent animals such as polar bears at risk. Species are changing their habitat ranges such as orcas, killer whales, now extending their habitat range to northwest Atlantic from the south Arctic due to rapid sea ice decline in the Arctic. Fishes are also changing their habitat ranges.

4. Snow cover has reduced in many places of the Arctic due to high precipitation but in the form of rain instead of snow as temperature rises. Rain-on-snow events, in which rain falls on top of snow, changes the ice structure and creates hard ice crusts which inhibit the growth of vegetation and grasses upon it, threatening the grazing of herbivores in the Arctic such as caribou.

Other components in the Arctic are also getting influenced due to global warming. 

There are other climate components besides sea ice in the Arctic that are vulnerable to global warming: Permafrost and Greenland ice sheet.

The permafrost is thawing in the Arctic region, due to global warming and long-trapped carbon dioxide and methane gases, which are major greenhouse gases, are being released into the atmosphere, further contributing to global warming and hence creating a feedback cycle. The permafrost have an vital role in maintaining the wetlands and lakes across the Arctic tundra. The wetlands provide habitats for many species of animals and plants and are breeding grounds for many bird species such as waterfowl and shorebirds. The permafrost thawing threatens to drain these wetlands.

Greenland, second largest ice sheet in the world after Antarctic ice sheet. It is more vulnerable to climate change than the Antarctic ice sheet because it is located in the Arctic region and is subjected to Arctic amplification (polar amplification).

Due to the alarming rate of warming of the Arctic Ocean, the Greenland ice sheet is melting at a faster pace, contributing to the sea level rise.

The Greenland ice sheet is gradually shrinking due to climate change due to extraction and burning of fossil fuels such as coal, oil and natural gas.

1. Meltwater is streaming into the ocean, adding freshwater to it causing sea level to rise and this addition of fresh meltwater may disturb ocean current patterns and thereby affect the climate of the region.

2. This meltwater sweeps down through cracks in the ice sheet further accelerating the melting and in some areas, allows the ice to slide more easily over the bedrock below, speeding its movement to the sea.

Ice and snow melts in Greenland during the summer warmth. The scientists estimate that meltwater of Greenland has caused around 25% of global sea level rise over the last two decades.

1. Increasing algae growth (as a result of climate change) on the Greenland sheet darkens the ice sheet, making it to absorb more sunlight thus driving more rapid melting. Algae naturally grows on the ice sheet but it requires a warmer climate to thrive. 

2. Oceans are warming due to temperature rise and the warm oceans are melting the Greenland ice sheet and now becoming a major threat to Greenland.

Mass of ice that has been lost by warming is to be offset by increased precipitation of snow due to increased temperature in the region, since temperature rise leads to more evaporation and precipitation.

Warming in the Arctic influences not only the Arctic region but the whole of the planet as the warming in the Arctic means sea level rise, changing weather patterns, changing temperature and precipitation, devastating floods and other extreme weather events.

Mainly three events are occurring in the Arctic region.

1. Loss or decline of sea ice.

2. Melting of Greenland ice sheet.

3. Permafrost thawing.

The Arctic Council

Arctic Warming vs Forest Fires

The frequency and intensity of forest fires and wildfires are increasing in the Arctic tundra as the Arctic climate warms and this warming is causing the methane emission from the Arctic tundra.

Recently Siberia has seen unprecedented wildfires in 2022 which result in 35% more carbon dioxide emissions than the 2019 wildfire event because of its highest ever recorded temperature in the summer.

The fires and warm weather may cause the permafrost and peatlands to thaw which result in carbon dioxide and methane to be released into the atmosphere. Arctic sea ice decline is linked to decline of boreal forest.