Democracy Has Prevailed.

May 14, 2014

The Braintrust Confuses Antarctic "Sea Ice" and "Ice Sheet"

In today's Tribune-Review (the op-ed page), the braintrust writes:
The West Antarctic ice sheet has begun falling apart, two papers published in the journals Science and Geophysical Research Letters conclude. And many of the usual players in the “climate change” game are sounding the alarms of gloom, doom and holy moley pumpkin pie, we're all going to die.

But curiously not mentioned in The Times' report — and woefully too few other reports — is this salient fact:

East Antarctic sea ice coverage reached a record 3.5 million square miles in April, reports the National Snow and Ice Data Center. And the center says ice formation thus far in May continues at a record pace. The development has caught more than a few climate scientists by surprise — which is what happens when data that contradict the theology of global warming are ignored.
Thus "confirming" the "two sides to every story" meme and further "confirming" that only one side is being told by the climate scientists.

Too bad they get their science wrong.

You see, my friends, there's a difference between the Antarctic ice sheet (which, when melted would contribute to a rise in sea levels) and the Antarctic sea ice (which, when it freezes and melts, doesn't).

The braintrust tries to show how this debunks the climate science evidence of global warming.  Too bad the very same page that pointed out the data of the Antarctic sea ice, we can read:
However, across much of the far Southern Hemisphere, temperatures have been above average: for example, in the southern Antarctic Peninsula, temperatures have been 1 to 2 degrees Celsius (2 to 4 degrees Fahrenheit) above average; in the southern South Pacific, temperatures have been 1.5 to 2.5 degrees Celsius (3 to 4 degrees Fahrenheit) above average, and up to 4 degrees Celsius (7 degrees Fahrenheit) above average in the area near the South Pole.
So how can it be that a warmer climate can cause more Antarctic sea ice?

Skeptical Science has the answer:
Antarctic sea ice has shown long term growth since satellites began measurements in 1979. This is an observation that has been often cited as proof against global warming. However, rarely is the question raised: why is Antarctic sea ice increasing? The implicit assumption is it must be cooling around Antarctica. This is decidedly not the case. In fact, the Southern Ocean has been warming faster than the rest of the world's oceans. Globally from 1955 to 1995, oceans have been warming at 0.1°C per decade. In contrast, the Southern Ocean has been warming at 0.17°C per decade. Not only is the Southern Ocean warming, it is warming faster than the global trend.
And then:
If the Southern Ocean is warming, why is Antarctic sea ice increasing? There are several contributing factors. One is the drop in ozone levels over Antarctica. The hole in the ozone layer above the South Pole has caused cooling in the stratosphere (Gillet 2003). This strengthens the cyclonic winds that circle the Antarctic continent (Thompson 2002). The wind pushes sea ice around, creating areas of open water known as polynyas. More polynyas lead to increased sea ice production (Turner 2009).

Another contributor is changes in ocean circulation. The Southern Ocean consists of a layer of cold water near the surface and a layer of warmer water below. Water from the warmer layer rises up to the surface, melting sea ice. However, as air temperatures warm, the amount of rain and snowfall also increases. This freshens the surface waters, leading to a surface layer less dense than the saltier, warmer water below. The layers become more stratified and mix less. Less heat is transported upwards from the deeper, warmer layer. Hence less sea ice is melted (Zhang 2007). An increase in melting of Antarctic land ice will also contribute to the increased sea ice production (Bintanga et al. 2013).

In summary, Antarctic sea ice is a complex and unique phenomenon. The simplistic interpretation that it must be cooling around Antarctica is decidedly not the case. Warming is happening - how it affects specific regions is complicated.
Amazing what happens when you actually look at the science.

And it's amazing how stupid you look when you don't.

1 comment:

Unknown said...

Great post! Do you send stuff like this directly to the T-R editors? Do they ever respond back? If I were an editor, I'd be embarassed and humiliated. What happened to the time-honored editorial tradition of fact-checking before you let something hit the printed page?