Good Sunday Morning!
75 years ago today, Canadian uranium from Saskatchewan loaded in a nuclear warhead detonated, destroying the Japanese city of Nagasaki. The radionuclides from that chain reaction continued to poison people for long after in radioactive fallout.
One reader reminded me last week of Toyama and the other cities destroyed in that dreadful first week of August. Conventional fire-bombing, aimed at demonstrating the new technology of the B-29 bombers, destroyed Toyama and many other cities in Japan.
“In total, 8,000 sorties dropped roughly 54,000 tons of incendiary bombs on 66 cities, killing (by conservative estimates) about 180,000 people. The attacks burned 76 square miles of urban Japan to the ground.” NPR August 1, 2020
So, yes, we remember Hiroshima and Nagasaki today – and yes, we must commit to nuclear disarmament and press Canada to sign and ratify the U.N. Treaty to Prohibit Nuclear Weapons. But we must also remember Toyama and so many other cities….And we really do not need new fighter jets.
To other news, the climate emergency continues apace. Flooding, tornadoes, fires, including the heat wave and fires in Siberia, loiter at the edge of our consciousness amid the non-stop COVID news. The July 24th Sunday New York Times Magazine was entirely devoted to the unparalleled threat of mass human migration. The NYT sets out the threat and the reality of climate refugees. By 2050, from sea level rise alone, 150 million people could be displaced.
This week came truly terrifying news:
“The last fully intact ice shelf in the Canadian Arctic has collapsed, losing more than 40% of its area in just two days at the end of July, researchers said on Thursday.” Reuters Aug 6, 2020
The Milne ice shelf on the edge of Ellesmere Island was larger than Manhattan. I have actually been to Ellesmere Island. Back in 1986, I had only just started my job as senior policy advisor for the federal minister of environment when I pushed the final negotiations to completion to create Ellesmere Island National Park Reserve – now known as Quttinirpaaq National Park. And then I had to organize a September signing on Ellesmere itself, as (properly) demanded by the NWT minister, Tagak Curley. Curley went on to play a key role in achieving territorial status for Nunavut. But September was a bit of a risky time for three Twin Otters to fly ministers and media, tables, chairs and flags to Tanquery Fjord. The deal, in English, French and Inuktitut, was signed just 750 km from the North Pole. I got a real education on the details and risks as the weight load per plane had to include survival gear in case the weather shifted and we got stuck there.
I regard that fleeting experience on Canada’s most northern extreme as one of the great privileges of my life. I saw herds of muskox running across the snow and one cheeky Arctic fox peered at us from a distance.
And now it is falling apart. An ice shelf – our last fully intact ice shelf – has been felled by global warming. To my surprise, the Friday night television news on CTV and Global featured this event, but CBC- “The National” did not mention it.
Impacts of loss of Arctic ice are felt around the world. The ice that forms on the water surface has been thick enough to support hunters and polar bears for millions of years. It is generally referred to as “multi-year ice.” The reflective power of the surface ice creates the albedo effect. The white ice bounces much of the sun’s radiative heat back out to the atmosphere.
It has been one of the more famous “surprises” for climate scientists that the positive feedback loop from melting Arctic ice has so dramatically increased the speed at which ice is lost. When the ice melts, dark ocean water is revealed. It does the opposite of the albedo effect; it sucks up the sun’s heat thus heating ocean water faster and leading to more ice melt.
An ice shelf, such as the Milne Shelf that just fell apart, forms along the edges of a land mass, but is also primarily surface ice. The ice shelves form from where glaciers run down a coastline. They can be enormous, as was Milne, but they are also floating. (Exploring the Environment - Ice Shelves).
So it is important to remember that when we lose an ice shelf, sea level rise is not impacted. Just as when you have a glass of ice tea filled with ice cubes, as they melt, the drink does not spill over the edge. The loss of any floating ice still has serious knock on effects – loss of the albedo effect and, because the ice releases fresh water, there is a serious impact on ocean currents. The fresh water sits on top of the heavier salty water and has the effect of depressing currents. Loss of Arctic ice has contributed to slowing the Gulf Stream, with serious impacts to climate globally. One reason that the Gulf of St. Lawrence is so threatened is that the Gulf Stream which used to bring colder oxygenated water into the productive gulf has been increasingly displaced by warmer de-oxygenated water from the Labrador Current. What happens in the Arctic does not stay in the Arctic.
Ice sheets are different. Two key “tipping points” that must be avoided would be losing the Western Antarctic Ice Sheet or the Greenland Ice Sheet. Because ice sheets sit on land, if they are lost, dislodging their mass to the sea, does impact sea level rise. According to the global consortium called the GRACE project (Gravity Recovery and Climate Experiment satellite system), loss of the Western Antarctic Ice Sheet could result in 8 meter sea level rise for Canada. One of GRACE’s principle researchers, Dr. Richard Peltier from the Physics Department at University of Toronto, explained it to me as being like the effect of water sloshing in a bathtub. A large displacement of water at the South Pole will slosh more water to our shores, than if the relatively nearby Greenland Ice Sheet was dislodged into the ocean. To avoid these tipping points, it is critical to keep global average temperature at no more than 1.5 degrees C (the Paris target).
All our estimates for sea level rise, including the one from the Sunday Times of 150 million people displaced, are based on a much less drastic scenario in which sea level rises due to water expansion. Warmer water takes up more room than colder water- so those estimates of sea level rise hold to around 1-1.5 meters rise. An 8 meter rise, or if both ice sheet losses occur a 16 meter rise, is not in current calculations.
Sorry if this seems a depressing Good Sunday Morning! The good news is that if we act decisively and stop using fossil fuels as quickly as possible, we can hang on to no more than a 1.5 degrees C global average temperature increase. It will not be easy, but it is totally do-able. We just have to take climate science as seriously as we take COVID science.
And since this was a lot of information to absorb all at once, take that glass with all the ice – skip the ice tea – and (once the sun is past the yardarm) have something stronger!
Stay well! Stay safe!
Love and thanks,
Just in case you missed it, federal Greens called this week for stopping construction of Site C. https://www.greenparty.ca/en/media-release/2020-08-06/cut-losses-and-end-site-c-dam-fiasco-says-green-party-canada
We also called for Environment Minister Wilkinson to reject Roberts Bank: https://www.greenparty.ca/en/media-release/2020-08-05/harms-outweigh-benefits-roberts-bank-terminal-2-expansion-says-green-mp
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