No, the blistering temperatures- recently felt in Europe - were no illusion or bad dream, as the map from the WSJ shows. (July 26, 'Europe Battles Record Heat And Drought', p. A1, A7). What gives? The past five years have been the hottest on record, including the record single year in 2016. The 10 hottest years have all occurred in the past two decades. The highest above-average conditions were recorded across Alaska, Greenland and large swathes of Siberia. Large parts of Africa and Australia were warmer than normal, as was much of Central Asia.
Meanwhile, last summer's high temperatures and low rainfall in Europe scorched crops and pastures from England to Germany - causing river levels to fall so low that transportation on major arteries such as the Rhine ground to a halt. Contrast that with the image of the Rhine below - near the Swiss-German border- which was from our visit in 2014:
Which has almost single-handedly generated the recent European heat wave. As I've written in previous posts on climate change- global warming, the warping of the jet stream is itself tied to greenhouse warming. Typically, it keeps cool air near the poles, but if the Arctic heats up, as our data shows, then the air over it becomes unstable. Thus, in the winter, we behold Arctic amplification". In papers and seminars delivered at the Geophysical Institute over 1985-1990 Prof. Gunther Weller first pointed out that a much warmer Arctic also means a much more unstable polar region with more frequent intrusions ("waves") of the polar vortex, leading to frigid temperatures in parts of the U.S. such as we've seen the past few years. In the summer, an opposite sort of effect manifests - as shown in the diagram with warm, dry air being trapped within a 'buckling' jet stream. According to climatologist Jennifer Francis - quoted in The Financial Times, 'Climate Change: How The Jet Stream Is Changing Your Weather', Aug. 6):
"The climate change aspect is contributing to these very persistent, big waves of the jet stream."
Further, she believes the undulations of the jet stream are becoming bigger, more pronounced, because of climate change. This take almost exactly follows Prof. Weller's earlier models for Arctic warming and the consequences from an unstable jet stream.
This inevitably means the current phase of warming is uneven, mainly because the Arctic is warming much faster. This is because the decrease in sea ice means the ocean is absorbing more heat from the Sun. This alone is causing many unforeseen consequences from the spreading noxious Sargassum seaweed around he Caribbean, to the proliferation of Great Whites and other sharks near U.S. shores, as well as the noisome outbreaks of the "red tide". Other less reported phenomena have also emerged but which few know or have read about, That includes the spread of an antibiotic -resistant fungus, Candida auris, and the increase in the size of hornets and wasps as an adaptation to warmer temps.
As the temp difference between poles and tropics narrows the jet stream will weaken further and the swings in shapes will become much more dramatic
One thing we've learned in the past three months, is the heat is not simply going to abate. We are now living in highly unusual climatic times, and this even before 200 cubic km of ice disappeared from Greenland in July alone. More recently, the sudden melting of 11 billion tons of Greenland ice in one singular event, sending a massive fresh water input into the North Atlantic - likely affecting the thermohaline circulation.(THC)
The currents associated with the THC ensure warmer water (such as in the Gulf of Mexico) and are transported to the northern hemisphere. Hence, it's actually a part of the greater scale ocean circulation. The applicable concern hearkens back to a theory of Dr. Walter Broeker - then a geo-scientist at Columbia University- who hypothesized that a sufficiently large discharge of fresh water (e.g. fro melting ice) into the North Atlantic would dramatically lower surface water density( Fresh water is less dense than salt water of the normal sea). Then the lower density water would not sink and hence not pull warm surface water from the equator up towards Europe.
The paradoxical result? The Earth, initially in the throes of global warming, would now see Europe plunged into another ice age on account of the thermohaline current disruption - from melting ice and higher precip - arising from (you guessed it) global warming.
For an insight into the Thermohaline circulation:
It is instructive at this point to look at the Earth's greenhouse gases and their forcing contributions as well as removal times.
Table
1: Removal times and climate forcing values for specified atmospheric gases and
aerosols (up to the year 2000).
Greenhouse gases:
Carbon Dioxide >100 years, 1.3 to 1.5 W/ m2
Methane ~ 10 years, 0.5 to 0.7 W/ m2
Tropospheric Ozone 10-100 days, 0.25 to 0.75 W/ m2
Nitrous Oxide 100 years, 0.1 to 0.2 W/ m2
Perfluorocarbon Compounds >1000 years, 0.01 W/ m2 (Including SF6)
Fine Aerosols:
Sulfate : 10 days -0.3 to -1.0 W/ m2
Black Carbon: 10 days 0.1 to 0.8
Greenhouse gases:
Carbon Dioxide >100 years, 1.3 to 1.5 W/ m2
Methane ~ 10 years, 0.5 to 0.7 W/ m2
Tropospheric Ozone 10-100 days, 0.25 to 0.75 W/ m2
Nitrous Oxide 100 years, 0.1 to 0.2 W/ m2
Perfluorocarbon Compounds >1000 years, 0.01 W/ m2 (Including SF6)
Fine Aerosols:
Sulfate : 10 days -0.3 to -1.0 W/ m2
Black Carbon: 10 days 0.1 to 0.8
Stendel - like Prof. Weller before him- acknowledges these can appreciably exacerbate effects of climate change, and are little understood by the general population. As he explains (ibid.)
"We have background warming and we have enhancement due to the non-linear effects, like the changes in the general circulation."
This, of course, has major implications for the melting ice sheet
and means that sea levels could rise faster than expected. The most recent report from the UN Intergovernmental Panel on Climate Change forecast between 45cm and 82cm of sea level rise by the end of this century if emissions keep increasing. A growing number of scientists think that may be too low.
Indeed. And right now my take is that climate scientists need to do a better job of educating the general public - using basic thermal physics- on the import of forcing and non-linear changes. This could also help the mainstream media get a better handle on reporting climate change events, and avoiding errors like sloppy conflation, and minimizing the import of climate catastrophes - such as with Hurricane Maria hitting Puerto Rico in 2017. See e.g.
The Media Are Complacent While the World Burns | The Nation
Excerpt:
"Judging by the climate coverage to date, most of the US news media still don’t grasp the seriousness of this issue. There is a runaway train racing toward us, and its name is climate change. That is not alarmism; it is scientific fact....The US mainstream news media, unlike major news outlets in Europe and independent media in the United States, have played a big part in getting it wrong for many years. It’s past time to make amends....
News stories about Hurricane Maria’s devastation of Puerto Rico, this spring’s floods in the Midwest, and other extreme-weather events almost never mention climate change, though scientists have been drawing the connection for decades. Instead, human-interest fluff prevails. In an 18-month period, TV and print outlets gave 40 times more coverage to the Kardashians than to the acidification of oceans caused by excessive amounts of carbon dioxide.
This journalistic failure has given rise to a calamitous public ignorance, which in turn has enabled politicians and corporations to avoid action. According to polls by Pew and others, as recently as the 2016 presidential race, only half of the people in this country said they thought that climate change was occurring and was attributable to human activities, and only 27 percent said they knew that almost all climate scientists held this view."
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The most profound aspect of all the recent events is that global warming leading to planetary catastrophe may well be unstoppable. The reason? Not only the release of methane from peat bogs and Arctic tundra but now the discovery the rate of CO2 concentration increase has amped up.
It has now accelerated from 400 ppm in 2013 to 415 ppm now. That is an approximately 6 year interval for a per year change in concentration of :
(415 ppm - 400 ppm) / 6 yr = 15 ppm / 6 yr = 2.5 ppm/ yr.
This is 25 % higher than the previous average rate of increase, i.e. 2.0 ppm/ yr. Given we know that every increase in CO2 concentration by 2 ppm increases the radiative heating effect by 2 W/ m2, we also know that the associated radiative heating is now significantly higher. The spike over 'natural variability' is clearly evident below:
This junp in concentration accounts for a major part of the increase of atmospheric temperature with CO2 concentration. It also is not on the radar of most of the national media. This is clear when one grasps on reading most media accounts that most climate reports (like the IPCC one cited earlier) understate the threat, See e.g.
Climate report understates threat
Excerpt:
"So far, average temperatures have risen by one degree Celsius. Adding 50 percent more warming to reach 1.5 degrees won’t simply increase impacts by the same percentage—bad as that would be. Instead, it risks setting up feedbacks that could fall like dangerous dominoes, fundamentally destabilizing the planet. This is analyzed in a recent study showing that the window to prevent runaway climate change and a “hot house” super-heated planet is closing much faster than previously understood."
The job of the media is now to convince citizens of the global commons that climate change is no longer merely an inconvenient, intermittent nuisance but an existential threat. One that will wreak havoc with increasing intensity and devastation over the coming years.
See also:
And:
Climate report understates threat
Excerpt:
"So far, average temperatures have risen by one degree Celsius. Adding 50 percent more warming to reach 1.5 degrees won’t simply increase impacts by the same percentage—bad as that would be. Instead, it risks setting up feedbacks that could fall like dangerous dominoes, fundamentally destabilizing the planet. This is analyzed in a recent study showing that the window to prevent runaway climate change and a “hot house” super-heated planet is closing much faster than previously understood."
The job of the media is now to convince citizens of the global commons that climate change is no longer merely an inconvenient, intermittent nuisance but an existential threat. One that will wreak havoc with increasing intensity and devastation over the coming years.
See also:
And:
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