Tuesday, August 7, 2018

Gimme Swelter!


Most of us who know that climate change is real have clearly linked the horrific hurricanes/ cyclones, fires, droughts, floods, disappearance of species and coastal erosion to that nasty. We know that mankind’s release of fossil fuels, beginning with the industrial revolution to the present day, offers a direct statistical correlation to rising average global temperatures.  Sweltering summers in places that have never been so hot, even north of the Arctic Circle, are an obvious result, and even the warmer northern Gulf Stream air is responsible for pushing cold Canadian air down through our Midwest and eastern seaboard, sending extra shivers through colder winters.
A few of us are even aware that parts of the world are slowly going to be completely uninhabitable well within this century. While we believe those areas will limited to the vast existing deserts, from the Sahara to the Gobi where temperatures will be so high that virtually no life could exist on those scalding surfaces, but areas that will not reach those temperatures but, because of a combination of humidity and simple human tolerance of sustained heat, major populated areas where external heat will kill so many people that living there will be simply too risky. Further, to the extent those areas are currently food-producing centers, the loss of arable land will render livelihoods and regional economies to reduced or no real value. To make matters worse, farming techniques, urban sprawl and changes in land-use patterns will only amplify rising patterns of concentrations of heat.
To understand this approaching catastrophe, which just may hit northern China the hardest, it is necessary to understand the underlying measurement, the Wet Bulb Temperature (WBT), which addresses the ability of the human body to evaporate sweat at higher temperatures. Picture sweating and then turning on a fan. The temperature remains the same, but the evaporating sweat from the moving air cools the body.
A WBT of 35 degrees Celsius (95 degrees Fahrenheit) can easily prove fatal. Simply, the inability of the skin to cool itself through evaporation leads to death within six or fewer hours even for a young and healthy human. The frequency of that level of heat is still sufficiently rare… but scientists believe that at the current rate of increasing heatwaves, such devastating realities will impact hundreds of millions of people with a very heavy death toll.
A Massachusetts Institute of Technology (MIT) study recently published in the journal Nature (nature.com, July 31st) focused on some of the most concentrated population centers on earth… in China. Here are some of their findings:
“North China Plain [a large area around Beijing] is likely to experience deadly heatwaves with wet-bulb temperature exceeding the threshold defining what Chinese farmers may tolerate while working outdoors…
“The … Plain… with an area of about 400 thousand square kilometers, is the largest alluvial plain in China. This region, inhabited by about 400 million, is one of the most densely populated in the world. The rich soils in this region were formed by sedimentary deposits from the Yellow, Huai, and Hai rivers, providing excellent conditions for agriculture. The rainfall levels are relatively low compared to similar locations in South China, making irrigation necessary for supplementing soil water during the spring to early summer growing season. This fertile plain has experienced vast expansion of irrigated agriculture which impacts significantly the surface radiation, surface energy balance, and boundary layer development in ways that impact surface humidity, and temperature. In observations that describe regional climate patterns, NCP stands out as a hot spot in the China-wide map of the maximum wet-bulb temperature (TWmax) observed in the last few decades. Given these past observations, the region is expected to remain vulnerable to heatwaves in the future…
“The frequency and intensity of heatwaves observed in China has increased significantly during the last 50 years as documented by several studies. Severe heatwaves have been experienced in China, particularly since the beginning of the twenty-first century. The surface mean temperature averaged over China has increased by about 1.35 °C during 1951–2006, a rate of about 0.24 °C/decade, which is larger than the corresponding global rate of about 0.13 °C/decade during 1956–2005. In July and August of 2003, extremely hot weather conditions lasting for 20–50 days occurred at many sites over South China. During this period, the daily maximum temperature recorded in many locations south of Yangtze River was above 38 °C. Heatwaves extended across most of China in 2006, with daily maximum temperature reaching 35 °C at 22 stations in Chongqing, Central China. In summer 2013, a severe heatwave event occurred in Eastern China. The daily maximum temperatures in many stations were extreme, breaking the historical records. Around Shanghai, the 141-year temperature record was exceeded, and the heatwave resulted in the death of dozens of people.
“Studies on heatwaves often (but not always) focus on surface temperature as the main variable used for characterizing their intensity. However, consideration of surface humidity is as important as that of surface temperature in defining heatwaves, since humidity impacts how humans feel heat stress.”
Sometime in the second half of this century, the frequency of WBTs over 35 degrees Celsius in China will increase to such a level that working outdoors will no longer be feasible. Construction workers. Farmers. Anybody who cannot escape their work to go to air-conditioned enclosures. Will machines replace people? Of course, but then you have to ask yourself if it will be worth building huge buildings in that climate or even if the land will be capable of sustaining commercial agriculture.
And that’s just China. The rest of the world also experienced a litany of extreme climatic conditions last year, and if you have been looking at the news, you know that 2018 has actually been a little worse. The prognosis for the same kinds of heat nasties in future years all around the globe is just plain ugly. The chart above, prepared by the government’s own National Oceanic and Atmospheric Administration (specifically, its National Centers for Environmental Information), very much a part of the Trump-led Department of Commerce, gives you a few of last years global climatic anomalies. It’s getting worse. It’s really killing people and destroying homes and livelihoods. Now. Today! And it’s costing trillions and trillions of hard dollars.
I’m Peter Dekom, and the failure of governments to act quickly and efficiently to stem this death-imposing greenhouse effect will result in more death and destruction (every species, human beings) than the world has ever seen before.

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