Erstellt am: 10. 10. 2013 - 14:34 Uhr
A black future for the Arctic?
You may know it best of it as soot, or dirty fumes, or the black gunge in the garden - but however you encounter it, we are all surrounded by black carbon.
The black carbon in the garden can be considered "good". It's full of nutrients, and it is needed for the life of plants. However, when black carbon is released to the air, it remains there for about two weeks, and can travel large distances. This is "bad" black carbon - and it poses a huge threat not just to our health, but also to the environment and the climate.
IIASA
Zbigniew (Zig) Klimont
To find out exactly why, I went to meet Zig Klimont at the International Institute for Applied Systems Analysis. He has been studying black carbon and its role in global warming, especially the warming of the Arctic.
This is a transcript of part of our conversation:
Why is black carbon important?
ZK: Recently, black carbon has been recognized as an important part of the climate system that contributes to warming of the atmosphere. When it's deposited on snow, it changes the reflectivity of the snow’s surface and accelerates the melting of the snow and ice.
Where is black carbon in the scale of all the pollutants and greenhouse gases?
ZK: A very recent study concluded that black carbon could be the second largest contributor to global warming after carbon dioxide. We are living in a time where we have not seen so little ice in the arctic as in the last years. 2012 was the lowest ice minimum ever recorded - which happens to be in September. So we might be facing a future, in the next few decades, without ice in September in the Arctic.
What did your latest study set out to do?
ZK: The original question was, could we do something to improve our understanding of the measurements that we have for the arctic. This is very important, because the Arctic has been found to warm about twice as fast as the rest of the globe.
We found that two key elements make a very significant impact. The first one was temporal, that is to say, seasonal. For example, you drive a car all the time, but you're more likely to burn your stove in the winter rather than in the summer. The other element was the flaring of natural gas that is there whenever you produce oil, or extract oil. There is often a lack of infrastructure to bring that gas to the consumers, so it is uneconomic. What happens is that this gas is either vented to the atmosphere, or converted to carbon dioxide through burning it off.
What can be done to get black carbon under control?
ZK: There are several options. This associated gas could, for example, be re-injected into the field after the oil is taken out, and this is something that industry has been doing for decades, but it’s not always done efficiently, and it’s not done in all countries. The other option that is, of course, the best in the long term, would be to reduce reliance on hydrocarbon fuels, like oil and gas.
There are a number of options for stoves, also. There are fairly good, efficient stoves already on the market, but it’s not just the technology. We also have to learn how the stove is operated, how much wood should be loaded, for example. Doing this correctly can save maybe even half of the emissions.
There’s another very unpopular measure, and that would be to move away from the logs that we like to watch when they burn to more modern pellets. They may not have the romantic glow of a log fire, but they are much more efficient and much cleaner.