March 2015

Summer Forecast: Hot, with Frequent Fires

Sometimes ICCI gets the question of how open field and forest burning, seeming quite far from the Arctic or other regions, can have such an impact at higher latitudes (or in the Himalayas, Andes or other mountain regions, on mountain glaciers and snowpack).  One explanation, of course, is the ability of black carbon particles of less than one micron in size, almost unbelievably small bits of soot, to travel great distances. These sometimes deposit thousands of miles from their origin, especially when lofted high into the atmosphere by the intensity of these fires.

A less-appreciated aspect has to do with warming that occurs closer to springtime agricultural fires, when snowpack remains in close proximity. The above picture, provided in near-real-time by the good scientists at NASA’s Goddard Space Flight Center, provides a strong visual example of this second kind of warming. It shows the seasonal impact of open burning at high-mid latitudes in northern Europe on higher-latitude – and ultimately Arctic – warming and melting: in this case, early-season fires surrounded by snow-covered regions nearby, where black carbon deposition from such fires can have a potentially powerful impact.

NASA MODIS Aqua satellite captured this image on February 17, 2015, of multiple fires[1] scattered throughout the Kaliningrad Oblast of Russia, where burning remains common, with no effective ban. (In contrast, Poland and the Baltic nations have longstanding policies against burning, dating back to their EU accession in the early 2000’s.) The smoke released by any type of fire (forest, brush, crop, structure, tires, waste or wood burning) is a mixture of particles and chemicals produced by incomplete burning of carbon-containing materials. All smoke contains carbon monoxide, carbon dioxide and, for cryosphere climate purposes especially, particulate matter or soot, commonly known as black carbon.

Surrounding these hotspots are large expanses of snow covering parts of Poland, the Baltics, Belarus, Ukraine and, to the north under cloud, the Nordic countries.  Black carbon from these fires deposited in surrounding snow-covered regions enhances melting of snow, leading to additional warming and melting. But the process does not stop there, as warming at these latitudes then leads to additional warming further north, in a step-wise fashion that eventually warms the Arctic.

Most Arctic scientists agree that this transport of high-mid latitude warming from black carbon on spring snowpack is as important as black carbon deposited directly in the Arctic.  This is in addition to the negative crop yield, health and infrastructure damage from fires.  Due to unusually warm and dry conditions in Russia (reportedly the warmest since 1891) and, likely, surrounding countries, fires are expected to be unusually difficult this year, with at least 1000 homes and 15 lives already lost by early April.

In terms of damaging fires and their impacts, it could be a very long and hot summer indeed.



[1] Each hot spot, which appears as a red mark, is an area where the thermal detectors on the MODIS instrument recognized temperatures higher than background. When accompanied by plumes of smoke, as in this image, such hot spots are diagnostic for fire.  Source:  http://phys.org/news/2015-02-central-europe.html#jCp

 

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