Wednesday, August 12, 2015

Sea Ice - Another Climate Science Denier Claim Melts Away

Climate science deniers are notorious for trying to dismiss climate change by cherry picking dates and massaging data in attempts to obfuscate signs that our planet is warming. In particular, science deniers attempt to downplay the shrinking of Arctic sea ice. They have two tactics for doing so:

  1. claiming that the decline in Arctic sea ice is counterbalanced by growth in Antarctic sea ice. Not only is this claim of  equivalence extremely misleading, currently Antarctic sea ice extent is not showing any increase versus the 1981-2010 average, thus even the misleading equivalence claim goes away (at least for this month)
  2. utilizing the variability of sea ice melt on a year by year basis by making comparisons of a year with extremely low extent to the current year. The clearly downward trend in Arctic sea ice extent can be obfuscated via cherry picking dates due to annual variability.

Arctic Versus Antarctic Sea Ice Extent

As shown in the images below, as of August 2015, Arctic sea ice is well below average extent, while Antarctic sea ice extent is about average. However, even in years when Antarctic sea ice is of above average extent, claims that they are offsetting are incorrect, as explained in posts from The National Snow & Ice Data Center and Skeptical Science. And a critical reason why they are not counterbalancing is the impact the warming arctic is having on the weather in the Northern Hemisphere. A number of researchers are conducting studies to determine if the weird winter weather in recent years resulting from the unusually wavy jet stream is due to reduced ice extent in the Arctic.

As illustrated in the above image, currently Arctic sea ice extent is more than 1.5 million kilometers below the average during 1981-2010. (Although not as low as during the record setting year of 2012).

The above image shows that as of August 2015, Antarctic sea ice has returned to average levels. Thus, the claims of climate science deniers that the sea ice extent at the two poles are offsetting have completely melted away.

Here is an example of the sea ice myth propagated by climate science deniers:
Arctic sea ice loss is matched by Antarctic sea ice gain. In fact, the global sea-ice record shows virtually no change throughout the past 30 years, because the quite rapid loss of Arctic sea ice since the satellites were watching has been matched by a near-equally rapid gain of Antarctic sea ice. Indeed, when the summer extent of Arctic sea ice reached its lowest point in the 30-year record in mid-September 2007, just three weeks later the Antarctic sea extent reached a 30-year record high. (Chris Monckton) 
Another prime example of a climate science denier mangling facts is provided by James Taylor of the Heartland Institute. In particular, note his use of the word "modest" in the quote provided below. Sorry, Mr. Taylor, but the loss of over a million square miles of Arctic sea ice is anything but "modest".
The alarmist assertion that polar ice sheets are melting is simply false. Although alarmists frequently point to a modest recent shrinkage in the Arctic ice sheet, that decline has been completely offset by ice sheet expansion in the Antarctic. Cumulatively, polar ice sheets have not declined at all since NASA satellite instruments began precisely measuring them 35 years ago.
 As shown in the above images, the claims by climate science deniers that Arctic and Antarctic sea ice extents are counterbalancing or that the decline is Arctic sea ice is "modest" are false.

Cherry Picking Data

In 2013, it was widely reported by climate science deniers that Arctic sea ice extent had increased by 29%. This was indeed true. But what made reports of the recovery of the Arctic sea ice extent misleading was that it was based on cherry picking a year with record low extent (2012) as the baseline year. 

A quick glance at the image below makes obvious that Arctic sea ice is not recovering, simply that the decline is variable from year to year. While the record low for Arctic sea ice extent in 2012 has not been matched during the last 3 years, based on the well established trend, a new record low is almost certain to be established within the next few years. Climate science deniers are notorious for comparing current year results to the data from record setting years, and thus trying to obfuscate the clearly established trends. Sadly, arctic sea ice is not recovering. In fact in 2015, it is likely that before the end of the melt season both the Northwest and Northeast passages through the Arctic will be ice free and navigable without the need for an icebreaker.


We live in a warming world. Climate science deniers go through all kinds of contortions to try to dispute this conclusion. But their clams that declining Arctic sea ice is "warmist" propaganda is currently completely invalid

Related Posts

Will Arctic Northeast Passage Be Ice Free By Late July in 2015?

Sea Level Rise May Be Accelerating in 2015

Cutting Through The Global Warming Debate: It's the Rising Sea Level, Stupid!

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