Tuesday 8 August 2017

Abrupt climate change in North America

Smoke Blankets Western North America, 106 F Temps in Portland, Flash Northern Plains Drought Threatens U.S. Wheat Crop

The climate change related impacts from continued fossil fuel burning just keep on ramping up.

7 August, 2017

Last Thursday, the mercury struck 106 degrees Fahrenheit in Portland, Oregon. The reading, just one degree shy of the hottest temperature ever recorded for the city, came after the thermometer soared to the 103 F mark on Wednesday. The extreme heat prompted some locals to re-name the typically wet and cool city — ‘Hotlandia’ — even as a broader severe heatwave blanketed most of the U.S. West.

(Smoke covers large portions of the U.S. West following record heat in many locales. Image source:NASA Worldview.)

During the weekend, the heat shifted north and east — thrusting 90+ degree (F) temperatures into British Columbia where severe wildfires have been raging throughout the summer. As a result, fire intensity spiked once again and great plumes of smoke today blanketed hundreds of miles of western sky.
In total, more than 575,000 hectares have burned in British Columbia so far this year. This is about 6 six times the average rate of wildfire burning for a typically wet and cool region. An intensification of the fire regime that came on as temperatures warmed, climates changed, and indigenous plants found themselves thrust into conditions outside those they’re adapted to.
The extreme heat was brought on by the kind of combined Pacific Ocean warming and upper level high pressure ridge amplification that some researchers have linked to human-caused climate change. And the overall impacts of the system have been as outlandish as they are notable.

(Extreme heat blankets the U.S. on Thursday, August 3rd. Image source: The National Weather Service.)

Further east, the high plains have suffered from extraordinarily dry conditions throughout spring and summer. Since April, rainfall totals have been reduced by 50 percent or more. The drying began with the start of growing season and has continued on through early August. After a rapid intensification during recent weeks, 62 percent of North Dakota and 38 percent of Montana are now blanketed by severe drought conditions or worse.

The drought’s center mass is near the Missouri River Basin — a primary water shed for the northern plains states. Since April, these key regions have seen as little as one quarter the usual precipitation amount. 

This equals the driest growing season ever recorded for some locations. And overall conditions are about as bad as they have been at any time in the past 100 years.

The result has been the emergence of a very intense flash drought. One of a type that has become more common as atmospheric temperatures have increased and as evaporation from waters and soils has intensified. At Lodgepole Montana, the heat and drought were enough to ignite a 422 square mile wildfire. Covering an area 1/3 the size of Rhode Island, the fire is Montana’s largest blaze since 1910. The fire is now, thankfully, 98 percent contained. More worrisome, the massive blaze is now accompanied by 9 smaller sister fires throughout the state. And all before the peak of fire season.

(Flash drought — a new phenomenon brought on by human-forced climate change — emerges in Montana. Image source: The US Drought Monitor and Grist.)

But perhaps the worst of the drought-related damage has impacted the region’s wheat crops. Andreports now indicate that fully half of the Northern Plains wheat crop is presently under threat. Overall current damage estimates for the Northern Plains drought alone are spiking above 1 billion dollars and states are now seeking emergency funding from a relief pool that the Trump Administration recently cut.

But regardless of Trump’s views on climate change or his related lack of preparedness, the damages and risks just continue mounting. Montana resident Sarah Swanson recently noted in Grist:
The damage and the destruction is just unimaginable. It’s unlike anything we’ve seen in decades.”
Sadly, with atmospheric carbon levels in the range of 407 ppm CO2 and 492 ppm CO2e, and with fossil fuel burning still continuing, these kinds of devastating droughts, heatwaves, and fires will just keep on getting worse.
Links:




No comments:

Post a Comment

Note: only a member of this blog may post a comment.