Tag Archives: NSIDC

Chart of the Day, 4 March 2015: Arctic Stories

Arctic sea ice extent is one of the most iconic indicators of climate change, but we usually give it most attention during the summer melt months. Nonetheless, I try to do a quick catch-up around the beginning of March, which marks peak extent. And this is what we see (Source: National Snow and Ice Data Center here; click for larger image):

Arctic Sea Ice Extent jpeg

Generally, winter ice is not a good predictor of summer ice extent, so I wouldn’t read too much into the fact that we are currently hitting new historical March lows in terms of what will happen this coming summer. That said, what we see in the above chart is still part of the general picture of new climate records being made across the board–especially in northern latitudes where warming is amplified.

The NSIDC is also hosting a series of stunning animated NASA satellite images that illustrate the changing nature of Arctic snow cover, vegetation and frozen ground as well as sea ice extent.  The frozen ground page has this inset chart showing the general thaw (click for larger image):

Nonfrozen Ground Anomalies jpeg

This, in turn, is increasing fears relating to methane release, although as I blogged about here, I still see this as a lesser risk than general CO2 emissions. The Global Carbon Project also has a good backgrounder on methane (here), including a methane budget showing sinks and sources (click for larger image):

Methane Graphic jpeg

At present, we have more to fear from ruminants, rice, landfills and fossil fuels, than from hydrates and thawing peat bogs.

Returning to sea ice, the ‘go to’ site is Neven’s “Arctic Sea Ice Blog” I’ll be checking in regularly to see if what we are seeing now with Arctic sea ice is just a blip or harbinger of another big melt season. Neven has also just highlighted a disturbing Ocean Geographic Magazine photo essay by Jenny Ross that is worth checking out. It’s a surreal and unnerving experience to witness the planet change dramatically before our eyes.

Preparing for the Arctic Melt Season

In 2012, the maximum Arctic sea ice extent was reached on 18 March at 15.24 million square kilometres according to National Snow and Ice Data Center (NSIDC). Nonetheless, this was far from a record low—indeed, only number eight historically. The year 2011 held (and still holds) pole position for the freeze season maximum low, at 14.64 million square kilometres.

However, for the 2012 melt season, we all know what happened next (or at least the sentient part of mankind knows what happened next). The NSIDC announced the crash in sea ice extent to 3.41 million square kilometres at its September 16 low (smashing the previous 2007 record of 4.17 million square kilometres) with all the gory detail here.

The upshot of all this? Basically, current sea ice extent won’t tell us if we will hit a new record low this coming September. So we need to be patient if we want to answer the big question of whether we will continue to see a jagged descent this year (with even a possible year-on-year marginal gain) or a further phase change (setting us up for an ice free summer Arctic within a decade). In other words, will the patient cling on for a while longer or opt for a quick death.

With two kids aged 11 and 16, this must be one of the most depressing data tracking exercises I have ever done. In short, my children will surely now inherit an ice free summer Arctic (and possibly spring and autumn too by their middle age), with all the consequences that this implies. But how quickly?

So what will I be looking at? First stop is always the NSIDC’s daily image update, which gives you this chart:

Arctic Sea Ice Extent jpeg

And while I am at the NSIDC site, I will be checking their new Greenland Ice Sheet Today page, which shows the latest domino to fall: Greenland ice sheet melt.

The only problem with the NSIDC image is that it does not contain a daily ice extent number. For that, I like the Japan-hosted IARC-JAXA Information System (IJIS) sea ice extent data series that can be found here. If you look at this series, then it is possible that we have already peaked for the year (but watch out for the last reported day to be always revised substantially).

Next, I go over to Neven’s incomparable blog for all things sea ice. Currently, Neven is reporting good news, bad news. The good news (well let’s say goodish news) is that sea ice volume (as opposed to extent) is above last year’s level. The bad news is that many parts of the Arctic sea ice are showing large unseasonal cracks that could herald further record sea ice lows in the months to come.

Neven’s site is also a chart fest and live-cam orgy. It is like having a ring-side seat of the sea ice collapse. Comments area also generally very interesting.

After that, I will periodically check on the Open Mind blog, in which Tamino will be statistically slaying the latest nonsense from Anthony Watts and his ilk (good example here). If you want to dust off your stats, read Tamino’s series of posts on ice sheet loss in preparation for the new melt season. They start here.

Finally, I will try to bring the dire state of the Arctic sea ice into conversations with those I meet. Most will, in turn, change the subject. Planeticide is such an unseemly topic—best not to talk about it and pretend it isn’t there.

New Risk Indicator: NSIDC Greenland Ice Sheet Melt Extent (Update)

Yesterday, I profiled a new risk indicator put out by the National Snow and Ice Data Center (NSIDC). The NSIDC is providing us with a new daily updated high-frequency time series, this time on Greenland melt extent, complete with daily images that can be found here. Click on the image below to expand.

Greenland Daily Melt jpg

The 2012 melt season was unprecedented, with 97% of the island showing melt at one stage in July. To yesterday’s post I just wanted to add an image which brings out just how exceptional the 2012 season actually was (click for larger image), which I took from the NSIDC site. The blue dotted line gives the average melt extent over the 1981 to 2010 average. Added to what we saw with Arctic sea ice extent last summer and northern hemisphere snow cover, the Greenland melt situation shows the degree of structural change we are seeing with  respect to Arctic and northern latitude climate.

Greenland Melt Extent 2012 jpg

A review of the year 2012 for Greenland by the NSICD can be found here. The critical question going forward is whether 2012 was a true anomaly or a harbinger of the new normal.

A similar argument was voiced some years ago over the 2007 Arctic sea ice extent retreat, with most scientists at the time urging caution over calling a trend break and suggesting that 2007 could have been a product of an unusual confluence of weather factors. After the 2012 sea ice extent retreat, which smashed the 2007 record, few would now argue against the trend being truly broken (with Arctic sea ice extent now in a state of collapse). I fear we may see a repeat performance with Greenland ice melt over the next few years.