I have reached a point in my studies where I can present my conclusions on what a melting of arctic likely means. Is it a sign of the apocalypse, or a natural phenomena?
First, I note with interest that the National Snow and Ice data center will be updating the sea ice baseline from the currently used 1979 to 2000 to the 1981 to 2010 interval. This means 10 years of diminished ice cover will figure into the average used for comparisons. This should result in the ice extent anomaly becoming smaller—in other words, the melt will be closer to average. In July, the change will be implemented and I look forward to seeing the effects.
Where to start? Studying arctic ice proved enlightening. There are many hypotheses for what causes ice melt. Plus, forces acting on sea ice are not the same as that acting on land ice. Land ice melts in reaction to air temperature, wind, storms, snow cover. Sea ice melts mostly due to water temperature underneath the ice, wave motion and storms.
There are terms:
slp sea level pressure
AO Arctic Oscillation
NAO North Atlantic Oscillation
lfo low frequency oscillation
sst sea surface temperature
enso el Niño southern oscillation
smmr scanning microwave radiometer
ssmi special sensor/ microwave imager
first year ice
multiyear ice (important because the two types of ice have different melting rates)
Beaufort Gyre (a mean annual clockwise motion in the Western Atlantic)
Then the proxies:
Marine sediment records
sea floor sediments beneath the ice give the best information
resolution varies by location—central areas are low resolution with a long time scale
continental margins are high resolution with a shorter time scale
ice rafted sediments are the most direct proxies
skeletons of marine animals/organisms
coastal records, driftwood, whalebone
terrestrial vegetation, ice cores
the 18O/16O ratio
Use of multiple proxies is required to reduce the probability of errors.
According to Lora Koenig, (Goddard glaciologist) a melt similar to the current one occurs every 150 years and this one is right on time. For those of you on the advocate side, I give you: http://www.dailykos.com/story/2012/07/28/1114628/-NASA-Made-up-150-year-melt-cycles-NY-Times-Slammed-NASA-for-Unprecedented-Melt-Every-150-Years#
It is a political blog with unlabeled axes on the first graph, but it does provide an alternative point of view (she was pressured by politics—wait—that’s what the questioners say about advocates. Now advocates who rejected that explanation when it was used as an explanation of why climate scientists all stick together and don’t go against “consensus”, are using the argument themselves. Most interesting.) I did not find verification of her political motivation. I did find other articles that verified the 150 year cycles based on ice cores.
Another interesting item was an announcement from NSID that they would revise their algorithm for the Greenland Ice Sheet early. The adjustment resulted in fewer melt days. What is interesting is how measurements are not straightforward. It seems we have to mathematically adjust so many of the measurements. Since no direct measurement may exist, there’s really no way to verify the accuracy, nothing concrete to compare to. The best we can do is have independent calculation and verify the “close fit” or “way off” nature of each method. The change in the algorithm appears to have been
due to temperature records showing the temperature had not hit the melting point. This is as close to direct verification as we get, it seems. This also illustrates the lack of reliability in the science, especially if the melt gets a headline and the correction gets virtually no notice.
In Quaternary Science Reviews, there was an interesting study on the history of sea ice. It explains proxies and many aspects of researching ice. The conclusion was “unexplainable by any of the known natural variations.” The implication was that humans were the only possible cause, not nature. This is basically the exclusionary principle—nothing else explains the phenomena so it must be “x” (in this case, us). In the study, this is not stated but rather implied. The actual conclusion is the ice melt is anomalous. That conclusion is an actual scientific statement that refrains from over-reaching: the ice is melting at a rate outside our defined “normal”.
In researching arctic ice, I found an article with a study saying the record surface melting was caused by “unusual atmospheric circulation and jet stream GrIS. This event was the largest such event since the 70’s and maybe longer. The study involved using a computer model and satellite data. Based on the results, the melt’s main forcing was atmospheric—the NAO, GBI (Greenland Blocking Index—a high pressure system over Greenland) and the polar jet stream. Researchers note that in time we will know if the was anomalous or part of an emerging pattern. Patience before drawing conclusions is a very good practice. So is more data collection.
Sea ice decline is actually small: -2.24% per decade. Headlines such as “Why Arctic Sea Ice will vanish in 2013” are designed to lead people to thinking climate change is much faster and larger than the data would indicate (I’ll wait until September to see if the headline comes true. Also, this story states we have had a stable climate for the last 11,000 years. Any time I ask about a stable climate, I am told “the climate never was stable”. It’s headlines and stories like these that lead people to asking when was climate stable and doubting the accuracy of climate change science.) I also found a report that Peter Wadhams, review editor, IPCC Working Group I report says the arctic will melt by 2015, if not sooner. The exaggerations seem endless.
One of the proxies used for study is historical records. I’m including some here. While there will be an immediate “That’s not science” reaction from many, consider that internet marketing surveys are now being published in peer-reviewed journals. Old newspaper headlines are certainly as reliable a measure as internet marketing surveys.
From Climate Depot:
1922 Washington Post “Arctic Ocean Getting Warm, Seals Vanish and Iceberg Melt”
1923 “Radical Climate Change Melting Down the North Pole”
1935 “Russian Ship Sailed 500 miles from North Pole in Ice Free Water”
1947 “International Agency needed to Stop the Arctic Meltdown” (No word on how that would work)
1907 “Arctic Heat Record—Hottest Place in Europe
Some of these may have been “local” events but the belief in apocalyptic meltdown of the arctic is nothing new.
As you can see, there are many theories/hypothesis on arctic ice melt. What seems most apparent is we lack sufficient understanding at this point to draw accurate conclusions, especially long-range ones. In 2002, satellites from GRACE began detecting tiny variations in Earth’s gravity that indicate changes in mass distribution on earth, including the movement of ice into the ocean. These are detecting decreases, but with only a decade of data, its too soon to establish a pattern as climate change rather than short-term weather changes. Even if we do find a significant decline, we cannot simply jump to “human-caused”. We live on a dynamic planet that is always changing. Monitoring may help us prepare for the changes by alerting us sooner, much like radar for tornadoes and hurricanes. Just like the storm alerts, the knowledge can only warn, not prevent. We can study, learn and adapt, but in all probability, it’s not something we control nor something we can prevent.
Polyak, L., et al, History of sea ice in the Arctic, Quaternary Science Reviews (2010)