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It seems that there’s been a lot of research news of late about the arctic climate. It’s something to think about because we’re mostly not in a good position to make the connection between what’s happening in those frigid, icy domains and the climate we experience on a daily basis. Here are a few things I’ve run across lately:
It's getting warmer up in the Arctic. Look at this graph, above.
It shows the average temperature measured at about 6 ft from the surface at a large number of arctic sites. The dotted line is the averages of those numbers over the period 1981-2010. This graph tells us that the temperature has been steadily rising, as measured by several different groups and organizations. The temperature has gone up about a degree Centigrade, or about 1.8 degrees Fahrenheit, since 1900. This does not seem like all that much. Notice however that the rate of warming has been accelerating alarmingly. In just the most recent two decades, it’s jumped up about two degrees Centigrade, about 3.5 to 4 degrees Fahrenheit. The message here is that a future warmer Arctic climate is arriving on an ever faster schedule.
A new article in Scientific American covers some of the consequences of what’s happening in the Arctic. “A new study finds that rapid warming in the Arctic—where temperatures are currently rising faster than anywhere else on Earth (the italics are mine)—may be altering certain summertime atmospheric circulation patterns in ways that affect the weather in North America, Europe, and other mid-latitude regions.” Because this warming is relatively new and coming on strong, all the answers as to what will happen to mid-latitude weather as a result of the warming are not yet in evidence. But some things we’ve already seen, and models furnish predictions of what may come. One strong effect is showing up: more persistent hot-dry extremes in the mid-latitudes.
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Some of the observed winter effects are counter-intuitive. A warmer, more ice-free Arctic can produce anomalously cold conditions further south, especially over Eurasia. There is a lot more to learn about the global climate effects, but we can be sure that the trends will accelerate in the years ahead. Just because climatologists have an incomplete understanding of how Arctic warming affects weather in the mid-latitudes, we can’t take the view that nothing much is likely to happen. Our recent summer and winter experiences are a mere warning of what is coming as the Arctic ice shrinks and then disappears, and Atlantic Ocean currents push warmer water into the Arctic.
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Then there’s the problem of the permafrost. I recently learned from an article in National Geographic that nearly a quarter of the Northern Hemisphere’s landmass sits atop permafrost. The figure that shows a view of Earth looking down on the North Pole shows us where it is. The darkest shade is permanent permafrost, and the lighter shades depict areas in which the permafrost may thaw to some degree seasonally. As you can see, there’s a lot of permafrost. The deepest parts have been there more than half a million years.
Then there’s the problem of the permafrost. I recently learned from an article in National Geographic that nearly a quarter of the Northern Hemisphere’s landmass sits atop permafrost. The figure that shows a view of Earth looking down on the North Pole shows us where it is. The darkest shade is permanent permafrost, and the lighter shades depict areas in which the permafrost may thaw to some degree seasonally. As you can see, there’s a lot of permafrost. The deepest parts have been there more than half a million years.
It’s estimated that twice as much carbon as is currently in the atmosphere is stored in the permafrost. But it's beginning to melt. As it does, microbes will begin to digest the stored vegetative matter, releasing carbon dioxide and methane. Just about everyone is now aware that methane is about 25 times stronger than carbon dioxide as a greenhouse gas, though it has a shorter lifetime in the atmosphere. These processes will add substantially to the increasing levels of greenhouse gases from the burning of fossil fuels and the many other sources we talk about.
To add to the problems associated with melting of the permafrost, measurements show that permafrost regions contain relatively large amounts of mercury, Hg. As melting occurs over the next century, that trapped Hg could be released. Not a good thing!!
The world’s oceans are warming. Even without El Niño, oceans surged to record-high temperatures last year as they absorbed the bulk of carbon dioxide from burning fossil fuels, deforestation and farming. The increased evaporation at the surface that results is “fuel for hurricanes and other storms,” said Kevin Trenberth, a senior scientist at the National Center for Atmospheric Research in Boulder, Colorado. Hurricane Lane is giving Hawaii a near miss as I write this. Catastrophic flooding has hit the big island and much more seems in store. Trenberth compared the storm in Hawaii to the floods in Kerala, India, that left at least 324 dead and 220,000 homeless a month or so ago. “The ocean heat content globally was at record high levels last calendar year and now it is higher still and the highest on record,” Trenberth said. “The hurricanes that do occur can become more intense.”
Unprecedented wildfires continued to scorch western states, choking cities like Seattle with smoke, a year after back-to-back storms wreaked havoc on Texas, Florida and Puerto Rico, and a wave of historic wildfires helped cause a record $306 billion in damages. No wonder then that James Temple dubbed 2017 in his article in the MIT Technology Review “The Year Climate Change Began to Spin Out of Control.”
Unprecedented wildfires continued to scorch western states, choking cities like Seattle with smoke, a year after back-to-back storms wreaked havoc on Texas, Florida and Puerto Rico, and a wave of historic wildfires helped cause a record $306 billion in damages. No wonder then that James Temple dubbed 2017 in his article in the MIT Technology Review “The Year Climate Change Began to Spin Out of Control.”
Meanwhile, the Environmental Protection Agency unveiled a proposal to replace the Obama-era Clean Power Plan with a rule that, by the agency’s own calculation, could cause 1,400 premature deaths annually by 2030 due to increased emissions. Optimists think that much of this eventuality is not likely to come to pass; coal is coming to the end of its run, despite Trump and his coal-friendly allies. “The world has shifted dramatically in the last few years to the point where we are going to get pretty close to the targets in the Clean Power Plan even without it,” said Jason Bordoff, director of Columbia University’s Center on Global Energy Policy. Anyway, just to make their point again, the White House has also put forward a proposal to gut fuel economy standards. It would allow vehicles to spew an additional 600 million metric tons of carbon dioxide ― equivalent to the annual emissions of Canada ― by 2030. I expect that there will be pushback against this absurd ruling on a state-by-state basis. The intransigence of climate change deniers is a thing to behold. United States Senator James F. Inhofe (R, Ok) is living demonstration that it is possible to be incorrigibly wrong-headed. Here he is: “I maintain that the best course of action remains to completely overturn the endangerment finding so that there is neither statutory nor legal need for any greenhouse gas regulations. I will continue to work with President Trump and Acting Administrator Wheeler toward this goal.”
We get caught up in the daily dueling and take cheer in whatever steps are made toward mitigating the emissions of greenhouse gases, but the fact is that a lot of damage already done will make itself felt far into the future. Even if we could stop immediately the emissions of all greenhouse gases, we’d still have something like the present 410 ppm of CO2 to contend with, an ocean that has warmed significantly, and glacial melting at a harrowing rate. And of course, we’re not stopping, or even abating the rate of additions of greenhouse gases.
I’m writing this from our summer home in Michigan’s Upper Peninsula. The headwaters of the Tahquamenon river lie about 35 miles to the east. Think of human society as a person in a canoe, moving with the beautiful dark waters of the river, which flows eastward through vast tracts of cedar. There is a future somewhere downstream, but there’s no reason to be concerned about it. Just lately, though, there’s been this slowly building sound of water rushing. How curious! What could it be? The Tahquamenon falls, the third largest falls east of the Mississippi River, has a drop of about 50 feet, and is 200 feet across. It will be tough to negotiate the falls in a canoe. Subscribe to This New World
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