Friday, 15 July 2016

Heatwave predicted for central US

Another Global Warming Enhanced Heatwave is on the Way — 111 Degree (F) Temperatures Predicted For Central US

14 July, 2016

It was in the 80s along Alaska’s Arctic Ocean shores yesterday. Record hot temperatures for a far northern region facilitated by factors related to human caused climate change such as warming ocean surfaces, sea ice melt, and an increasingly wavy Jet Stream.
(Record hot temperatures in the lower to middle 80s F [26 to 28 C] spread into the North Slope region of Alaska along the shores of the Arctic Ocean yesterday. And according to Dr. Jeff Masters, the 66 F [19 C] reading at Barrow tied its all time record high. Image source: Brett Brettschneider.)

But extreme heat along the northern reaches of Alaska appears now to be ready to morph into another record heatwave for the lower 48. For the past two weeks, weather models have been consistently predicting severe heat for the Central US. And with each passing day, as the forecasts grow evermore certain, the development of yet one more period of record hot temperatures becomes more and more likely.
An extremely tall dome of hot and heavy air is expected to build up over Colorado, Oklahoma and Nebraska. Heat beneath the dome and near the surface is expected to intensify. By the middle of next week, temperatures over a continuous large swath from Northern Texas to Montana and the Dakotas is predicted to experience near or above 100 degree F (38 C) temperatures. By late week, some of these readings could peak at around 111 degrees Fahrenheit (44 C) for parts of Central Nebraska.
(Saturday, July 24 GFS model forecast shows severe heat settling over the Central US. It’s the kind of heatwave that is now more and more likely to occur due to human-forced climate change. Image source: Pivotal Weather.)

These temperatures are expected to range 18-25 F (10-14 C) or more above typical July averages. And if temperatures do hit so high, they will likely make a number of new record highs for this region of the US.
By Sunday, the heat is expected to sprawl both east and west. And high temperatures near or above the Century mark could ultimately stretch in a great triangle from Alabama west to the Central Valley of California and north to Montana’s Canadian Border.
Conditions in Context — Human-Caused Global Warming, Hot Ocean Surfaces

This extreme heat comes in the context of record hot global temperatures. During 2016, global surface temperatures are likely to range near 1.2 degrees Celsius above the late 19th Century average. These record temperatures have been spurred by greenhouse gasses spiking to levels not seen in millions of years. CO2 concentrations this year hit near 408 parts per million at the Mauna Loa Observatory — a level high enough to significantly further increase global temperatures, melt large glaciers, substantially raise sea levels, and prevent another ice age for thousands or tens of thousands of years. And continued burning of fossil fuels by human beings will likely push that number near or above 410 parts per million by May of 2017.