Showing posts with label hydroxyl. Show all posts
Showing posts with label hydroxyl. Show all posts

Monday, August 12, 2013

More on Wildfires


Previous posts have highlighted the huge amounts of carbon dioxide, methane and soot being emitted as a result of wildfires. Apart from this, there are further important pollutants to consider in regard to their potential to contribute to warming, especially at high latitudes.

The image below, dated August 7, 2013, and kindly supplied by Leonid Yurganov, shows high levels of carbon monoxide as a result of wildfires in Siberia, reaching high up into the Arctic all the way to Greenland. 

[ click on image to enlarge ]
Formation of tropospheric ozone mostly occurs when nitrogen oxides (NOx), carbon monoxide (CO) and volatile organic compounds (VOCs) react in the atmosphere in the presence of sunlight. NOx, CO, and VOCs are therefore called ozone precursors. Apart from a health hazard, tropospheric ozone is an important greenhouse gas. Furthermore, carbon monoxide emissions contribute to hydroxyl depletion, thus extending the lifetime of methane.

While there appears to be little or no carbon dioxide from wildfires over North America on the above August 7 image, there are many recent wildfires raging over the North American continent, as illustrated by the August 12 map below, from Wunderground

[ click on image to enlarge ]
This point is illustrated even better on the image below [added later, ed.] showing a composite image with carbon monoxide over July 3-13, 2013. Carbon monoxide resulting from wildfires in Canada is seen crossing the Atlantic Ocean, due to the Coriolis effect, as well as reaching Greenland in large amounts.

[ click on image to enlarge ]


Related

- Wildfires even more damaging
http://arctic-news.blogspot.com/2013/07/wildfires-even-more-damaging.html

- The Threat of Wildfires in the North
http://arctic-news.blogspot.com/2013/06/the-threat-of-wildfires-in-the-north.html

- Wildfires in Canada affect the Arctic
http://arctic-news.blogspot.com/2013/07/wildfires-in-canada-affect-the-arctic.html

Sunday, March 18, 2012

Warming in the Arctic

Note: this is a 3.4 MB animation that may take some time to fully load. 

Loss of snow and ice can change local temperatures significantly, especially in April/May.

The changes contribute to accelerated warming in the Arctic, which - as the image left shows - is projected to reach 10 degrees Celsius in the 2040s.

Temperatures could rise even faster in the Arctic as methane gets released from hydrates. 

Methane's global warming potential is 105 times as much as carbon dioxide over a 20-year period, and even higher over a shorter period. 

How much methane is there?


Of all the methane located in the Arctic, 50 Gt is ready for abrupt release at any time in the ESAS alone (squared area, image left). 

Such a release would dwarf warming by carbon dioxide from fossil fuels (~ 33 Gt/y), given methane's high immediate global warming potential. 

When released from a hydrate, much of the methane will remain concentrated locally, amplifying local warming.  

For this reason, even a much smaller release could already cause dramatic local warming. There are further reasons why this is the case.  

Such a release will extend methane's lifetime, while lack of hydroxyl in the Arctic (image left) could further make the methane stay there for decades, at a high global warming potential, while triggering further releases.

Meanwhile, rising temperatures will cause firestorms to rage over the tundras of Canada and Siberia, releasing huge amounts of greenhouse gases and soot from peatlands and soil carbon. 

The recent firestorms in Russia provide a gloomy preview of what could happen as temperatures keep rising in the Arctic.  

The image below illustrates how much organic carbon is present in the melting permafrost.  

Much of the soot from firestorms in Siberia could settle on the ice in the Himalaya Tibetan plateau, melting the glaciers there and causing short-term flooding followed by rapid decrease of the flow of ten of Asia’s largest river systems that originate there, with more than a billion people’s livelihoods depending on the continued flow of this water.