July 11, 2019

Degraded Permafrost In The Arctic

Listen Later

2 minutes

Permafrost is defined as rock or soil that has been at or below the freezing point of water for two or more years. Most of it is located in high latitudes in and around the Arctic and Antarctic regions. Permafrost covers nearly a quarter of the exposed land in the Northern Hemisphere.

Permafrost can contain many different materials including bedrock,

sediment, organic matter, water and ice.

Because of the presence of organic matter, permafrost is potentially the

source of significant methane emissions if it thaws and the trapped biomass

begins to rot.

A recent study looked at the results of 30 years of aerial surveys and

extensive ground mapping of an area of Canada’s high Arctic polar desert known

as the Eureka Sound Lowlands. This area

has an extremely cold climate and the permafrost there is over 1/3 of a mile

thick. It has long been assumed that

this landscape was stable.

Research led by McGill University in Montreal has found that this is

not the case. The increases in summer

air temperatures seen in recent years are initiating widespread changes in the

landscape.

A particular landform known as a retrogressive thaw slump that forms

when ice within permafrost melts and the land slips down is widely occurring in

the area. The absence of vegetation and

layers of organic soil in these polar deserts make permafrost in the area

particularly vulnerable to increases in summer air temperatures.

The research indicates that despite the cold polar desert conditions

that characterize much of the high Arctic, the interaction between ice-rich

permafrost systems and climate factors is complex and the links between global

warming and permafrost degradation are not well understood.

**********

Web Links

Widespread permafrost degradation seen in high Arctic terrain

Photo, posted August 11, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

...more

View all episodes

View all episodes

Download on the App Store

Download on the App Store

Get it on Google Play

Earth Wise

By Randy Simon

4.7

1515 ratings

July 11, 2019

Degraded Permafrost In The Arctic

Listen Later

2 minutes

Permafrost is defined as rock or soil that has been at or below the freezing point of water for two or more years. Most of it is located in high latitudes in and around the Arctic and Antarctic regions. Permafrost covers nearly a quarter of the exposed land in the Northern Hemisphere.

Permafrost can contain many different materials including bedrock,

sediment, organic matter, water and ice.

Because of the presence of organic matter, permafrost is potentially the

source of significant methane emissions if it thaws and the trapped biomass

begins to rot.

A recent study looked at the results of 30 years of aerial surveys and

extensive ground mapping of an area of Canada’s high Arctic polar desert known

as the Eureka Sound Lowlands. This area

has an extremely cold climate and the permafrost there is over 1/3 of a mile

thick. It has long been assumed that

this landscape was stable.

Research led by McGill University in Montreal has found that this is

not the case. The increases in summer

air temperatures seen in recent years are initiating widespread changes in the

landscape.

A particular landform known as a retrogressive thaw slump that forms

when ice within permafrost melts and the land slips down is widely occurring in

the area. The absence of vegetation and

layers of organic soil in these polar deserts make permafrost in the area

particularly vulnerable to increases in summer air temperatures.

The research indicates that despite the cold polar desert conditions

that characterize much of the high Arctic, the interaction between ice-rich

permafrost systems and climate factors is complex and the links between global

warming and permafrost degradation are not well understood.

**********

Web Links

Widespread permafrost degradation seen in high Arctic terrain

Photo, posted August 11, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

...more