Permafrost covers roughly a quarter of the entire northern hemisphere
Unfortunately, it's also located in the most remote and hard-to-get-to places
so very few people actually have been to a permafrost region.
Because of that, it's often overlooked
Permafrost contains a huge amount of frozen organic matter
There's twice as much carbon frozen in the permafrost as there is in the atmosphere today.
As this permafrost thaws out, so to will the organic matter. Which will decay and release
carbon dioxide and methane to the atmosphere.
this will amplify warming due to the burning of fossil fuels.
Temperatures are rising twice as fast in the high latitudes as it is for the global average
So permafrost right now is beginning to warm up and its starting to thaw out
We went up to Toolik lake to do ground penetrating radar surveys to measure the thaw depth
of the permafrost, and we did this in order to validate our satellite radar product.
What we measure from space with satellite radar is actually the frost heave
as the surface layer freezes and thaws. As water in the surface freezes it expands, and the ground goes up
and as it thaws in the summer, the ground goes down. That tells us how much water has frozen and melted
in the active layer, or the thawing layer.
We have to make sure that what we actually measure from space is, in fact really what we think it is
and we do that using a ground penetrating radar
This is a radar that is about the size of a shoe box and you drag it along on the tundra
and it sends out a signal and it reflects off the frozen permafrost and comes back and it tells us
the thaw depth. It's very important to know how much ice is actually in the permafrost.
Permafrost, you can visualize it as frozen dirt, but within the permafrost there is a huge amount of ice
in the form of layers, and lenses, and wedges, and blocks.
Of course, when the permafrost thaws out, this ice melts and drains away and the soil collapses.
So it's extremely important to know how much ice is actually in the permafrost.
When talking about permafrost and permafrost change, there's two things that we look at
one is the temperature within the permafrost at various depths, and the second is the depth of the active layer
now as temperatures have been going up due to climate change the active layer has been getting thicker
which means its thawing deeper and deeper, but the bigger response is the permafrost itself
Permafrost itself actually takes a long time to respond to changes in climate
and the key think to realize about that is that as the temperature temperature of the permafrost goes up
nothing is going to happen to that permafrost until it reaches zero degrees centigrade
The permafrost temperatures right now deep down are actually still responding to little ice age 600 years ago
So as climate changes now permafrost is changing, but it's always going to be slow,
it's always going to take a long time.
So its going to take a couple of hundred years for this to thaw out, decay, and release the carbon dioxide
into the atmosphere. So it's going to take a long time, but also, once it starts, it can't stop.