Search Results for Tag: CO2
Live like millions of years ago?
You might not have realized it, but last Friday something quite historical happened: For the first time since the Pliocene (about five to three million years ago) CO2 concentration in the atmosphere crossed the 400 parts-per-million limit. The last time that much carbon dioxide was in the atmosphere, the Arctic was ice-free, the Sahara desert was a savanna and the sea level was 40 meters above today’s level.
Measuring this carbon level is kind of a family business: More than 50 years ago, Charles Keeling started measurements on the dead Mauna Loa volcano, where air quality is very good. Back then, in 1958, CO2 concentration was around 315 ppm – compared to 280 ppm on preindustrial level. Today, his son Ralph Keeling continues the measurements.
The overall trend is increasing, though CO2 levels fluctuate periodically from winter to summer season, when plants naturally fix more carbon dioxide due to leaf growth. Scientists attribute this overall increase to anthropogenic CO2 emissions - mainly from burning fossil fuels.
Within the last ten years, CO2 concentration has risen by two ppm per year. If the world continues emitting carbon at this pace, the next important threshold is not far away (german link). CO2 concentration may not rise upon 445 ppm CO2 (445 molecules of carbon dioxide in one million molecules) if the two degree target is to be met, scientists of the Intergovernmental Panel on Climate Change (IPCC) say.
DateMay 15, 2013
Exploring the North – treasures under the ice cover
Our Global Ideas reporter Gianna Grün recently made a trip to the Arctic Circle and has written about tracking reindeer, an encounter with Sami herdsmen and sleeping in a hotel made entirely of ice. Check out her latest article from the freezing North.
What looks like a lovely winter wonderland landscape is in reality a perfect source for building material. No, I’m not talking about the few trees on the horizon – the resource slumbers below the snow cover! Hidden from the eye, the Torne river flows below the snow. Well, at least the part that’s not frozen. But the more interesting part is the ice cover. In March, i’s thick enough for ice block harvesting to begin.
Some 2,500 of such 1.8 ton blocks are cut out in March and April to build a new hotel made of ice near Kiruna, Sweden. When spring arrives in other parts of the world, the ice is in perfect condition for building a new hotel from scratch next winter. The ice is at least 80 centimeters deep and crystal clear due to the high water quality of the Torne river and its perfect velocity and depth. Upstream, the water flows too fast and stirs up sediment from the river floor. Downstream from here, the water is too still and lacking in oxygen so you get milky ice.
Though it is quite cold up here in the North, building doesn’t begin right after harvesting. While the old ice hotel is literally melting, the 5,000 tons of newly harvested ice are stored over the summer. From April until October, the storage hall is cooled to minus six degrees Celsius. That requires almost 240,000 kilowatts of energy, which comes from renewable sources. Between November and March, no cooling is required since the outside temperature is cold enough. Thanks to the massive blocks of ice and the isolation, the entire place stays cool enough.
When construction begins in winter, the ice hotel builders arm themselves with electric irons and smoothers. Well, not for cleaning their teeth or ensuring wrinkle-free shirts, but for the fine tuning. After chain saws, tractors, snow cannons, snow throwers, wheel burrows, spades and chisels have got the basics in place, the finer details, embellishments and sculptures are readied to give the whole space a cozier feel despite the cold.
It takes six to eight weeks to set up the whole hotel. Apart from ice, a special mixture of ice and snow called “snice” is used as a kind of mortar. In addition, some wooden structures are built in the ice to support the very high and steep arches and a few reindeer skins cover some surfaces.
Apart from offering visitors the unusual experience of sleeping in a room surrounded by ice, the hotel is also trying its hand not just at cutting its carbon output but actually becoming CO2-negative. So far, it’s reduced overall energy consumption by 20 percent. But in future, it aims to cut CO2 in its immediate surroundings by an amount that exceeds its overall energy consumption.
Do you know of similar projects that use building materials lying right at the doorstep, without harming the environment?
DateApril 11, 2013
Is the ocean to quit it’s job?
Silently and mostly unrecognized, ocean is doing a yet quiet good job for the climate: it absorbs CO2 from the atmosphere and dumps it into the deep. That is one of the reasons, why climate did not further heat up within the last decade – although world keeps emitting lots of CO2.
But now researchers found that the Atlantic ocean absorbs less CO2 than usually – and also figured out the reason for this. It’s because the so called “meridional overturning circulation” slows down. Before you now think “I’ll never get this” – hang on. Sounds more complicated than it actually is.
The overturning circulation works like this: In the Atlantic ocean, water flows northwards – from the warmer Southern part into the colder Northern part. There, the water cools down, becomes saltier and sinks into the deep. There this so called deepwater flows back towards the South, warms up there and is welling up in consequence. Back at the surface in the Southern hemisphere it is, where ocean water takes up the antropogenic CO2.
Now, due to global warming, also ocean surface water – even in the Northern usually colder part of the Atlantic – warms up – and does not sink to the deep. This in turn slows down the overturning circulation. In consequence of this slowing, CO2-saturated water is not dumped into the deep as usual, but stays rather close to the surface. In consequence, less CO2 can be taken up from the atmosphere.
So the research team scientifically proved that we actually are destroying those natural systems that normally help keeping CO2 levels low – by emitting more and more CO2 and warming up the planet with its ocean.
DateFebruary 24, 2013
TagsAtlantic ocean, carbon dioxide, climate change, CO2, global warming, ocean, overturning circulation
Keep to +2 degrees might not prevent permafrost from melting
Large parts of the Northern hemisphere from Alaska to China hold a dangerous treasure. 24 percent of this land’s ground is frozen throughout the year – so called permafrost. It holds more than 1,000 gigatons of the most dangerous greenhouse gases: carbon dioxide and methane. Release of those would accelerate climate change to great extend.
Now, researchers found evidence that permafrost could start melting already at a 1.5 degrees Celsius rise in temperature. Also, the world already warmed up by 0.6 to 0.7 degree Celsius compared to the preindustrial level. So adding another 0.8 could already let permafrost melt.
That’s at least what happened in former times, as the scientists from Britain, Russia, Mongolia and Switzerland found out. They went into Siberian caves located along the ‘permafrost frontier’ studying stalactites and stalagmites as they function as a kind of climate archive – they only grow when liquid rainwater and snow melt drips from the surface into the caves.
“The stalactites and stalagmites from these caves are a way of looking back in time to see how warm periods similar to our modern climate affect how far permafrost extends across Siberia”, said Dr Anton Vaks of Oxford University’s Department of Earth Sciences, who led the work.
The amplifying effect on global warming the release of greenhouse gases held in the permafrost would have, exceeds everything climate models yet suggest. So, though almost 200 nations agreed in 2009 to the 2 degree target for global warming, this may not be enough to keep permafrost from melting and thus to mitigate climate change.
DateFebruary 22, 2013
When climate pays for financial crisis
Once upon a time, politicians had a good idea for how to create incentives that make companies want to become greener. Companies were to buy certificates for the amount of carbondioxide they emitted – one certificate for every ton. The more carbon – the more certificates they had to buy. The less CO2, the less certificates. So far, so good.
Initially sold for 20 Euros a piece, the price of certificates rose to a record 32 Euros before embarking on a steady decline: At the end of January it dropped to an all-time low of 2,81 Euro. We were wondering what the reasons for and the consequences of this low price might be, so we’ve asked Christian Linden from the German Emissions Trading Authority to give us some input for our FAQ.
How come the price for emissions certificates is nose-diving so badly at the moment?
At present supply outweighs demand. That’s for a number of reasons: companies were allocated certificates too generously at the start of both, the initial and subsequent trading periods. Plus, the economic and financial crisis has led to a decline in industrial production, which in turn brought about a decline in CO2 emissions. As a consequence companies have accumulated a surplus in certificates, which is now flooding the market, bringing down the price.
Another argument could be that some companies have already became greener, which means they need fewer certificates (German source).
What happens if the price stays that low?
There is little incentive to invest in climate friendly technology, if it’s too cheap to carry on producing goods in a way that harms our climate.
What can be done to get the certificate prices to rise again?
In the short term, a good idea is what the EU commission has suggested: to temporarily keep a certain number of certificates – they are talking about 900 million – out of the market. In the longer run it’s important that on a political level an ambitious climate goal is agreed to reduce carbon emissions in the EU by 30 percent until 2020. This would raise the pressure on companies to reduce their emissions.
What’s the “right” price for a certificate?
It’d be a price that motivates businesses to reduce emissions and/or invest in climate friendly technology. For some companies this might start at 15 Euros a ton, fro others it may be closer to 25 Euros. So, here is no single “right” price.
DateFebruary 9, 2013
Tagscertificate, climate change, CO2, emission, emission certificate, emissions trading, green economy, low price