In the Arctic region, beyond 66½˚ N latitude, the ground is in a generally frozen condition for most of the year. Ice and snow are the normal landscapes. Even in the warm season, liquid water available is very shallow. Under this, the land remains shallow. Add to these the high-speed winds. Trees cannot grow in such a climate. However, life does exist. Nomadic people do live in these latitudes, though, as you can imagine, population density is very low.
Liquid water is vital for vegetation to grow, and for that vegetation to support animal life. However, the warm season is not very long, even though there may be 24-hour daylight in the summer. There is light, yes, but the sun’s rays fall at such a low angle that it is not very strong. Compare that to sunlight over the tropical latitudes – Tropic of Cancer (23½˚ N) to Tropic of Capricorn (23½˚ S) at the two extremes – where sunlight falls at 90˚ angle to the surface of Earth. These give us very hot temperatures at the height of summer (of course, subject to other climatic controls such as altitude, proximity to seas/oceans, vegetative cover, human alteration of the landscape, and the like).
As you move from the extremes of the tropical latitudes towards the poles, you encounter the temperate regions followed by the polar regions where the tundra is to be found. The northern hemisphere of Earth has more land mass than the southern and hence more tundra also.
Because there is life in the tundra, there is also death. When plants and animals die and fall into the shallow waters, they rot. Over successive warm seasons the rot continues and methane gas is released. But the freezing cold season keeps the methane trapped in the land because the ice – permafrost: permanent frost – won’t allow it come out.
In chemistry class you may have studied the properties of methane (pronounced “mee-thane” or “meth-ane”) which has the chemical formula CH4. Having both carbon and hydrogen, it is one of the hydro-carbons. It is released a lot all around us. In nature, when there is moisture, warmth, and low oxygen, the decay of dead organisms releases methane.
Human activities such as rice cultivation, burning fossil fuels (natural gas, coal, petroleum), and cattle rearing – all contribute methane to the atmosphere. Cows belching and … well, letting off wind at the other end … is among the sources of methane. Next time you go anywhere near sewage canal or drain, notice that ugly smell that makes you want to just puke. Well, that is not methane. That is more likely hydrogen sulphide and other smelly gases. Methane is colorless and odorless.
The smell of the gas used at homes to cook is due to an additive to make it smell bad so that we know if there is a leak somewhere.
This methane is deadly because we cannot easily detect its presence – except when it goes up in a flame. It is very highly flammable.
Thanks to the rising concerns over Anthropogenic (anthropo – human, genic – caused by) Global Warming (AGW), even our EVS and geography textbooks talk about greenhouse gases – gases in our atmosphere that hold back heat and contribute to warmer temperatures on Earth. Methane is one of the greenhouse gases.
You have likely studied atmospheric circulation in your geography class. This circulation distributes gases around the world and, thus, heat also gets circulated. So, atmospheric pollution in one part of the world ends up getting distributed all around. Greenhouse gases emitted in one place contribute to AGW worldwide. This is the point over which there is so much debate and bickering in the international community about who should do what and how much to reduce AGW.
In dramatic videos, scientists show us how AGW is releasing more and more methane from the Arctic region, where enormous quantities of methane lie trapped in the permafrost. This becomes part of a vicious cycle. AGW causes warming. This causes melting in the Arctic permafrost that, in turn, causes methane to be released. That methane then adds to the greenhouse effect, increasing global warming. That, in turn, melts more ice, more methane is released, … and so on. This is a very dangerous spiral.
If you have been following the news in the past few weeks, you will have learned about a huge “sink hole” in the Yamal peninsula of Russia. This large crater is 80 metres wide and slowly expanding as its sides melt and fall into the middle, depth still uncertain, as I write this. Russian scientists studying this say it may have been a result of methane bursting through weakened permafrost. If this is proved to be true, we have even more cause for alarm. Already, there are reports of other craters in the Arctic being reported by people living there. Where there are settlements (even if they are temporary), people’s lives are in immediate physical risk.
It’s pretty scary when you can’t even trust the ground you are standing on!
Things you can do:
- With your knowledge of climate and weather, identify other areas where you may actually find tundra-like conditions. (Hint: you will need to apply your knowledge of climatic controls to figure this out.)
- Watch a dramatic video about methane in the Arctic permafrost.
- Here is a more detailed clip about methane in the Arctic permafrost narrated by Professor Ian Stewart with Professor Katie Walter.
- Using your school atlas locate the Yamal peninsula and figure out its approximate latitudinal span (i.e., from which latitude to which latitude it extends) and longitudinal span (same for longitude). Notice its location in relation to the Arctic Circle (66½˚N).
- Read two very interesting articles about the Yamal crater: here (with an interesting short video clip) and a more technical article in the journal Nature.
(A version of this article appeared in the Deccan Herald Student Edition on 7 August 2014.)