It's The Beavers Fault!

[seer]

I knew we couldn't trust those buck tooth rodents!

Beavers are contributing to climate change, adding an estimated 800 million kg of methane to the atmosphere every year, scientists have found.

Over the last century, there has been a worldwide conservation effort to save beavers from extinction. The fur trade between the 16th and 19th century almost led to the annihilation of beavers across the globe.

After trapping was limited and the creatures were reintroduced to their natural ranges, their numbers grew significantly, with scientists now estimating their population to have reached over 10 million worldwide.

However, the consequence of this has led to beavers building more ponds, creating conditions for climate changing methane gas to be generated in the shallow standing water. Beavers build dams in rivers to create standing ponds, with dams normally reaching no higher than 1.5m.

http://www.ibtimes.co.uk/climate-cha...y-year-1479809

[Bill the Cat]

beaver.jpg

[Leonhard]

I knew we couldn't trust those buck tooth rodents!

Hmm... its not actually that farfetched that these rodents would end up having a non-neglible (but still small) contribution to the climate effect.

We know that methane is roughly thirty times more powerful than CO2 in terms of heat trapping. So if they estimated the increased methane output correctly, then these rodents would be the cause of an equivalant output of 24 million tons of CO2 per year. In the US, that translates roughly to the greenhouse gas output per 1.5 million people. So the beavers contribution would amount to 0.5% of the total output of greenhouse gasses from the US population. Not quite negligible, though it is a very small natural contribution.

When you're tallying up the natural causes of climate change you need to account for a lot of small contributions. In Denmark we had a similar study for the methane output of our cows and pigs giving similar numbers. Man still comes out on the top by more than an order of magnitude in terms of CO2 output, the others are either closed cycles, or so infrequent (volcano erruptions) that they average out to something much less.

[Darth Executor]