Wednesday, December 21, 2016

Lake Baikal

The amount of methane stored in the form of hydrates at the bottom of Lake Baikal in Siberia is an estimated 1 trillion m³, which translates into 424 trillion kg of methane, or 424 Gt of methane. By comparison, the amount of methane in the atmosphere is about 5 Gt.


Aral Sea
Methane hydrates remain stable under a combination of sufficiently low temperatures and sufficiently high pressure. The temperature of the water at the bottom of the lake is about 3.5°C. This means that a large amount of water needs to remain present in the lake at any time, in order to keep the methane hydrates stable.

Lake Baikal is the world's deepest lake. Due to its depth, Lake Baikal is also the largest freshwater lake by volume in the world, containing roughly 20% of the world's unfrozen surface fresh water. Lake Baikal has 23,615.39 km³ (5,700 cu mi) of fresh water and a maximum depth of 1,642 m (5,387 ft).

If the water level in Lake Baikal were to fall, the pressure on the methane hydrates would decrease, resulting in huge methane eruptions, dwarfing the amount of methane currently in the atmosphere.

What are the chances that water levels in Lake Baikal will fall in future? The above animation shows the fate of the Aral Sea, further to the west in Asia (also on the map at top). The Aral Sea virtually disappeared over the course of the last few decades. Some people point at climate change as the cause. More people point at irrigation by farmers.
Yenisei River

Lake Baikal could go the same way. Climate change may well reduce the flow of the rivers that now feed Lake Baikal from Mongolia (image right). Furthermore, climate change may well reduce crop yields worldwide as well as the availability of fresh water, increasing temptations to use the water of Lake Baikal for irrigation.

Further decline of Arctic sea ice is likely to push up temperatures across Russia. The image below shows that temperatures as high as 36.6°C or 97.8°F were forecast for June 13, 2016, over the Yenisei River in Siberia that ends in the Arctic Ocean.
[ click on images to enlarge or go to original post ]
Even higher temperatures were recorded in 2015 at a location in Siberia well within the Arctic Circle.

Demands for water could increase even more dramatically due to wildfires and the need to fight such fires. The image below shows that on June 23, 2016, wildfires north of Lake Baikal caused emissions as high as 22,953 ppb CO and 549 ppm CO₂ at the location marked by the green circle.

[ click on images to enlarge or go to original post ]
The situation is dire and calls for comprehensive and effective action, as described at the Climate Plan.


Links

 Climate Plan
http://arctic-news.blogspot.com/p/climateplan.html

 Gone: endemic Baikal sponge has died completely in several areas of the vast lake
http://siberiantimes.com/ecology/casestudy/features/f0278-gone-endemic-baikal-sponge-has-died-completely-in-several-areas-of-the-vast-lake/

 Volume to weight conversion
http://www.aqua-calc.com/calculate/volume-to-weight

 Lake Baikal, Wikipedia
https://en.wikipedia.org/wiki/Lake_Baikal

 Aral Sea, Wikipedia
https://en.wikipedia.org/wiki/Aral_Sea

 Climate Feedbacks Start To Kick In More
http://arctic-news.blogspot.com/2016/06/climate-feebacks-start-to-kick-in-more.html

 High Temperatures In Arctic
http://arctic-news.blogspot.com/2016/06/high-temperatures-in-arctic.html

 East Siberian Heat Wave
http://arctic-news.blogspot.com/2015/07/east-siberian-heat-wave.html

 Wildfires in Russia's Far East
http://arctic-news.blogspot.com/2016/08/wildfires-in-russias-far-east.html




6 comments:

  1. Worldwide, maybe a child could understand the math of hurtle jump, $ shark
    past equation www.physicsforum.com/insights/shwarzchild-geometry-part-1/ 72 trillion metric tonnes of CH4 are held in water ice lattice framework and it can't stand the Closed System Nature of politics to war. Heat rise.

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  2. I don't think lake Baika is such a threat due to how deep it is. Having it running dry is unlikely. I am far more concerned about methane hydrates from the warming Arctic.

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    1. I do agree that the situation in the Arctic is even more threatening, and I do agree that it's unlikely that Lake Baikal will run dry soon.

      Nonetheless, it's precisely because of its great depth that Lake Baikal does hold a lot of methane in hydrates, much of which could be released well before the lake would run dry. Indeed, the danger is that a fall in the water level, well before it would run dry, could cause huge amounts of methane to be released. This could occur rather abruptly if a drop in water level would put many of the most vulnerable hydrates on the edge. Another small fall in water level could then suffice to trigger explosive destabilization of just one of these most vulnerable hydrates which could send shock-waves through the lake that could trigger further eruptions.

      In conclusion, the situation calls for a comprehensive approach which was sadly lacking in the case of the Aral Sea.

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    2. We can begin a new tradition.
      We all know of "Indian Summer"
      Welcome to "Eskimo mild spell"
      Thanks for the article. Despite not a near future threat, at least we know what's there.
      If what happens in the Arctic doesn't stay in the Arctic, I wonder if and how this could impact the weather in the Northern hemisphere; things are getting really weird.
      Enjoy the holidays Sam, I hope they bring us peace and more knowledge.
      Takes care

      Jack

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  3. Over 400 Gt of CH4?! And to think I was worried about an estimated 50 Gt of CH4 in the Arctic. https://en.wikipedia.org/wiki/Arctic_methane_emissions#Contribution_to_climate_change Certainly the Arctic is a more 'immediate' threat. Once that gives way, it's only a matter of time before the lake's hydrates finish off the deed.
    After seeing Trump's cabinet picks and knowing Putin has shown favoritism of his victory this election I can't help but wonder how much time is really left. Either way this scenario plays out. I'm going to do my best to stick around until Gaya says, 'Time's up, Jeff'. She's helped provide me the gift of existence. It's the least I can do to show gratitude to her, the universe, and the unknown past visibility.

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    1. Yes, the situation in the East Siberian Arctic Shelf (ESAS) is most urgent. Back in 2010, Shakova and Semiletov warned that the ESAS region alone could contain some 1700 Gt in the form of free gas and hydrates under the sediment, in addition to organic carbon in its permafrost. Earlier, Shakhova et al. had classified up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time.

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