Cool summer of 2013 boosted Arctic sea ice

The volume of Arctic sea ice increased by a third after the summer of 2013 as the unusually cool air temperatures prevented the ice from melting, according to UCL and University of Leeds scientists. This suggests that the ice pack in the Northern hemisphere is more sensitive to changes in summer melting than it is to winter cooling, a finding which will help researchers to predict future changes in its volume.

The study, published in Nature Geoscience today and funded by the Natural Environment Research Council (NERC), used 88 million measurements of recorded by the European Space Agency's CryoSat-2 mission between 2010 and 2014. It showed that there was a 14% reduction in the volume of summertime Arctic between 2010 and 2012, but the volume of ice jumped by 41% in 2013 (relative to the previous year), when the summer was 5% cooler than the previous year.

Lead author and PhD student, Rachel Tilling from the Centre for Polar Observation and Modelling (CPOM), UCL Earth & Planetary Sciences, said: "The summer of 2013 was much cooler than recent years with temperatures typical of those seen in the late 1990s. This allowed thick sea ice to persist northwest of Greenland because there were fewer days when it could melt. Although models have suggested that the volume of Arctic sea ice is in long term decline, we know now that it can recover by a significant amount if the melting season is cut short."

The volume of Arctic ice has been steadily falling since the late 1970s but was difficult to assess accurately before CryoSat-2, which measures ice-thickness across the whole region. When compared to ~772,000 readings from an airborne laser, 430 measurements from electromagnetic sensors and 80 million upward-looking sonar observations, the team found that CryoSat's measurements of sea ice thickness agreed to within 2mm.

Miss Tilling added: "Until CryoSat-2 was launched, it was tricky to measure the volume of Arctic sea ice as the pack drifts and measurements could not be taken across the whole region. Together with maps of sea ice extent, our measurements of sea ice thickness now complete the picture because they reveal what's going on below the water, where most of the action happens."

The team say although the first five years of CryoSat-2 measurements have revealed important information on the state of Arctic sea ice, the record is still short to establish a long-term trend.

Co-author Professor Andy Shepherd, Professor of Earth Observation at UCL and at the University of Leeds, said: "Understanding what controls the amount of Arctic sea ice takes us one step closer to making reliable predictions of how long it will last, which is important because it is a key component of Earth's climate system. Although the jump in volume means that the region is unlikely to be ice free this summer, we still expect temperatures to rise in the future, and so the events of 2013 will have simply wound the clock back a few years on the long-term pattern of decline. Our goal is to make sure we do not lose this unique capability to monitor Arctic sea ice when the mission ends."

The team now plan to use CryoSat-2's measurements of changing sea to help improve the models that are used to predict future climate change, and also to assist maritime activities in the Arctic region, which can be dangerous and costly to navigate.


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Fast access to CryoSat's Arctic ice measurements now available

More information: Nature Geoscience. DOI: 10.1038/ngeo248
Journal information: Nature Geoscience

Citation: Cool summer of 2013 boosted Arctic sea ice (2015, July 20) retrieved 19 September 2019 from https://phys.org/news/2015-07-cool-summer-boosted-arctic-sea.html
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Jul 20, 2015
Wasn't that the year GRACE reported record surface melting of Greenland?

Greenland's land ice and the physical barrier there, serves as a "buffer" for the melting of the sea ice. The sea ice will most likely never completely melt until a much larger portion of Greenland's land ice finishes melting.

If Helena Popova's new Maunder Minimum prediction pans out, we could see a significant recovery of Arctic sea ice, and possibly even Greenland and Alaskan land ice, starting in the 2030 to 2040 decade and continuing for the next 20 to 30 years thereafter.

A 2.8W/m^2 (Lean et al) decrease in flux during the polar Summer would mean the rate of initial melting and the rate of positive albedo feedback would be greatly, greatly reduced, meaning that you would see a non-linear cooling effect in the poles, and potentially a non-linear increase in the amount of net accumulation of both land and sea ice.

This is my opinion based on Popova's model prediction.

Jul 20, 2015
The reason a flux change will affect the poles more than the equator, even though the poles receive less direct sunlight, is because the poles (and to a lesser extent the northern temperate zone) are where the self-reinforcing albedo effect is strongest; this is also known as "second order feedback".

This means that an initial linear change in forcing produces a greater than linear change in final net forcing. This is most commonly pointed out by AGW alarmists who claim CO2 is producing non-linear forcing. I would agree that "Global Warming" is producing non-linear forcing, but I do not agree that man-made portion of Global Warming is producing non-linear forcing, because we don't have enough data, and sea level rise in the past century (about a foot) was only barely more than sea level rise in the previous century (about 8 inches), even though CO2 levels more than doubled during that time. This shows CO2 related warming is at most LESS than linear.

Jul 20, 2015
The polar bears will be fine.- Freeman Dyson.

Jul 20, 2015
Bang...bang...bang... another nail in the AGW Cult's CO2 filled coffin of lies.

Jul 20, 2015
If we blamed ALL of the 4 inch discrepancy for the 1 foot rise in sea level from the 20th century on man-made CO2, and ignored the positive albedo feedback already set in motion by nature during the melting of the previous century(s), then at least 8 of the 12 inches of sea level rise in the 20th century are still 100% natural...without considering positive albedo feedback from the previous 8 inches worth of sea level rise, nor that second group o f8 inches worth of sea level rise.

What does all this mean?

It means that at the least, more than 2/3rds of all Global Warming during the 20th century was caused by sources other than human beings: Solar changes, and second order positive alebedo feedback (caused by the NATURAL melting of ice from 1800 to 2000). AT most, Only 4 inches of the 20 inches of sea level rise from 1800 to 2000 could be attributed to man-made CO2.

Jul 20, 2015
The polar bears will be fine.- Freeman Dyson.


"We found that polar bears appear unable to meaningfully prolong their reliance on stored energy, confirming their vulnerability to lost hunting opportunities on the sea ice—even as they surprised us by also exhibiting an unusual ability to minimize heat loss while swimming in Arctic waters," says John Whiteman, the UW doctoral student who led the project.

Read more at: http://phys.org/n...html#jCp

Jul 20, 2015
A few months ago, there was an article on here about a Polar Bear which captured dolphins (i think) which were trapped in a pocket of water surrounded by ice.

A normal animal might have killed one of the dolphins, at it, and then gone about its business.

The polar bear displayed abstract thinking and planning ahead, however. It killed both of the dolphins, ate one of them, and then buried the other dolphin in the snow so it could find it later.

Even dogs aren't that smart. Dogs will bury the left-overs of something they couldn't finish, but dogs don't go out of their way to kill EXTRA, and then bury the extra for later use.

Lol.

The polar bears will be fine...indeed.

Jul 20, 2015
Only 4 inches.....

Understandably, that's huge to the AGW Chicken Littles.

Jul 20, 2015
Yeah that one year of extent increase totally blows long-trends out of the water. Low base, anybody. Do a stats course. Or in antigoracle's case, learn to read.

Jul 20, 2015
Yeah that one year of extent increase totally blows long-trends out of the water. Low base, anybody. Do a stats course. Or in antigoracle's case, learn to read.


Extent is a bad metric anyway, because its too susceptible which way the wind blows on a given day.

People who talk seriously about the issue prefer area and volume because they are more consistent with respect to trends.

https://sites.goo...egraphs/

If you look at the Volume graph, we have actually recovered by about 2 or 3 thousand cubic kilometers of sea ice compared to the lowest years in the past 2 decades for the same month.

Neat, huh...

The scaremongers didn't mention that little detail.

Dug
Jul 20, 2015
"Cool summer of 2013 boosted Arctic sea ice July 20, 2015." I suggest the authors get novel and Google "summer 2013 hottest on record." Depending on which article your read from that year - 2013 was some where between 1st and 9th for the hottest ever recorded. Folks we really have to be consistent in our statements in the press, otherwise we might look like we have a bias.
.

Jul 20, 2015
"Cool summer of 2013 boosted Arctic sea ice July 20, 2015." I suggest the authors get novel and Google "summer 2013 hottest on record." Depending on which article your read from that year - 2013 was some where between 1st and 9th for the hottest ever recorded. Folks we really have to be consistent in our statements in the press, otherwise we might look like we have a bias.
.


Or, one might take a moment to consider the context, perhaps leading to an understanding that the Arctic is not representative of the globe as a whole.

Jul 20, 2015
It's not a case of consistency. People will deliberately misread what they want to misread.

They're talking about comparative Arctic temperatures over time - not global temperatures. It can be relatively cooler in the Arctic one year while being one of the hottest years on record. Just like we can see a large proportional variation off a low base in one year when compared to the two years before it.

Deniers will leap on anything and twist it any way they like. It's not an excuse for us not to continue to catalogue the world as it actually is.

Personally, with the way things are constantly twisted, misused and misread, I'd like to see every article like this with a context statement for how it fits into climate science overall. But we can't expect researchers to have to cater constantly for ignorance, determined denial and stupidity.

Jul 20, 2015
This is actually a fascinating measurement. What it demonstrates is that with a 5% cooler atmosphere, Arctic ice volume can increase 41%. Wow, we have global warming solved. All we need to do is make the planet 5% cooler! I think we need to have an immediate BAN on CO2 production until we achieve a 5% cooler atmosphere!

Thanks to all of the deniers for helping to make the case for fossil fuel's total and complete elimination..

Jul 21, 2015
This is actually a fascinating measurement. What it demonstrates is that with a 5% cooler atmosphere, Arctic ice volume can increase 41%. Wow, we have global warming solved. All we need to do is make the planet 5% cooler! I think we need to have an immediate BAN on CO2 production until we achieve a 5% cooler atmosphere!

Thanks to all of the deniers for helping to make the case for fossil fuel's total and complete elimination..

Wow howhot, yours is a special kind of stupid, as in you are special.
How is this cooling related to CO2 levels?

Jul 22, 2015
And they're stuck in ice on Hudson Bay. Now. In July!

Jul 22, 2015
I have written down a few thoughts on denial and the impending ice age

https://dameholly...-denial/

Jul 23, 2015
I have written down a few thoughts on denial and the impending ice age

https://dameholly...-denial/

Congratulations.
Now, if you can only learn to read.

Jul 27, 2015
This is actually a fascinating measurement. What it demonstrates is that with a 5% cooler atmosphere, Arctic ice volume can increase 41%. Wow, we have global warming solved. All we need to do is make the planet 5% cooler! I think we need to have an immediate BAN on CO2 production until we achieve a 5% cooler atmosphere!

Thanks to all of the deniers for helping to make the case for fossil fuel's total and complete elimination..

Wow howhot, yours is a special kind of stupid, as in you are special.
How is this cooling related to CO2 levels?

There is always a exponential rise in CO2 prior to and at the beginning of a Ice Age. As well as a exponential increase in volcanic activity. Imagine that! Oh wait, its not imagination!! It is happening NOW!

Jul 27, 2015
[
There is always a exponential rise in CO2 prior to and at the beginning of a Ice Age. As well as a exponential increase in volcanic activity. Imagine that! Oh wait, its not imagination!! It is happening NOW!


Typical denier, making ignorant and false claims he read on a doomsday sight with something to sell.

Jul 27, 2015
[
There is always a exponential rise in CO2 prior to and at the beginning of a Ice Age. As well as a exponential increase in volcanic activity. Imagine that! Oh wait, its not imagination!! It is happening NOW!


Typical denier, making ignorant and false claims he read on a doomsday sight with something to sell.


Typical denier? What are you talking about? Scientific fact with actual recorded evidence. Now how exactly is that ignorant? False claims? Is called reality! But it seems as far as the reality goes you are surely lacking of it!

Now you could google EDIS and USGS. If you wish to find more factual information. Really do not have time for people with non-substantive accusations.

Aug 12, 2015
Only 4 inches.....

Understandably, that's huge to the AGW Chicken Littles. -antigoracle

Since beach slopes are anywhere from a few to 30 degrees, that represents an inland intrusion of the sea of anywhere from 8 inches to 10 feet. 10 feet would be a substantial intrusion for most beach-front property owners. It appears that amongst your many failures, we must count high-school trig.

Aug 12, 2015
A 10cm sea level rise doubles the risk of flooding in coastal areas. We've had a 20cm rise. Do the math.

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