Over the last few months I’ve been reporting regularly about the record-breaking temperatures that have taken place all over the world, particularly within North America. Since this is the time of year when the Arctic ice cap is melting, wouldn’t we expect a warming planet to lead to more ice melting at the North Pole than has usually been seen in past years? If global warming is truly happening, can we see evidence of it in Santa’s neck of the woods?
Turns out that’s exactly what we’re seeing. Sea ice at the North Pole decreased so rapidly last month it broke the 2007 record. It was the most sea ice lost in the month of June since satellites have been able to accurately record the phenomenon. The total amount lost was measured at 1.1 million square miles, an area equal to the states of Alaska, Texas, California and Florida combined. At the end of June, the amount of sea ice lost was about three weeks ahead of schedule, and this is about 456,000 square miles below the average seen in the twenty year span from 1980 to 2000.
The next few months will confirm whether or not 2012 will be the worst loss of Arctic sea ice since satellite data has been available, because the minimum amount of polar ice isn’t reached until the month of September. It’s always possible that other factors could affect the present trend before then, but at this point it seems quite likely. As it stands, the trend is favouring this being the year with the greatest loss of Arctic sea ice in recorded history.
According to the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado, significant sea ice was lost in Beaufort, Bering, and Kara Seas, as well as in Baffin and Hudson Bays. In fact, the only region in the northern hemisphere with an above average amount of sea ice at the end of last month was the eastern coast of Greenland.
The NSIDC attributes the rapid loss of ice to the above-average temperatures the northern hemisphere has been experiencing as well as a lack of snow cover. According to them, “This rapid and early retreat of snow cover exposes large, darker underlying surfaces to the sun early in the season, fostering higher air temperatures and warmer soils.”
The Arctic is warming at a rate about twice that seen in more southern latitudes within the Northern Hemisphere. That’s due in part because of the positive-feedback mechanisms that occur in the Arctic climate. As warmer temperatures lead to the brighter and more reflective sea ice melting, more of the darker ocean is exposed which will do a better job of absorbing light from the sun and leading to more infrared radiation released.
I refer to this phenomenon in my book Comprehending the Climate Crisis. The following is found on pages 84-85.
“[T]he loss of ice on our planet means there will be less sunlight reflected back into space. White snow and ice, such as that on Earth’s poles and glaciers, is much more reflective than the blue ocean or most of the land masses. This reflective property is referred to as albedo; the higher the albedo, the more reflective the planet’s surface is.
As Earth loses some of its ice to global warming, the planet’s albedo will decrease. More sunlight will be absorbed rather than reflected back into space, and this will lead to greater amounts of infrared radiation produced.
The heat that results will of course remain trapped within the insulating effects of the greenhouse gases in our atmosphere and contribute to even greater temperature increases. The entire process has the very real possibility of becoming a runaway reaction, feeding into itself with a never-ending cycle of increasing temperatures, melting ice, decreasing albedo, increased absorption of sunlight, increased infrared radiation, increased global temperatures, and so on.”
Melting sea ice is one reason the Arctic is considered one of the best and earliest markers of global warming. It’s our canary in the coal mine. (Funny how that phrase also relates to fossil fuels.)
The warming trends in recent years have been concerning indeed, and if we continue to witness greater losses of sea ice in the coming years, I’m afraid the writing will already be on the wall for our planet’s fate. We won’t be trying to prevent a climate crisis any longer. We’ll be trying to minimize it.
If September’s sea ice minimum breaks records, perhaps it’s a sign that point has already come.