Global warming will progress faster

Global warming will progress faster than what was previously believed. The reason is that greenhouse gas emissions that arise naturally are also affected by increased temperatures. This has been confirmed in a new study from Linköping University that measures natural methane emissions. 

"Everything indicates that global warming caused by humans leads to increased natural greenhouse gas emissions. Our detailed measurements reveal a clear pattern of greater methane emissions from lakes at higher temperatures," says Sivakiruthika Natchimuthu, doctoral student at Tema Environmental Change, Linköping University, Sweden, and lead author of the latest publication on this topic from her group.

Over the past two years the research team at Linköping University has contributed to numerous studies that all point in the same direction: natural greenhouse gas emissions will increase when the climate gets warmer. In the latest study the researchers examined the emissions of the greenhouse gas methane from three lakes. The effects were clear and the methane emissions increased exponentially with temperature. Their measurements show that a temperature increase from 15 to 20 degrees Celsius almost doubled the methane level. The findings was recently published in Limnology and Oceanography.

While increased anthropogenic emissions of greenhouse gases are expected and included in climate predictions, the future development of the natural emissions has been less clear.

Now knowledge of a vicious circle emerge: greenhouse gas emissions from the burning of fossil fuels lead to higher temperatures, which in turn lead to increased natural emissions and further warming.

"We're not talking about hypotheses anymore. The evidence is growing and the results of the detailed studies are surprisingly clear. [DB1] The question is no longer if the natural emissions will increase but rather how much they will increase with warming," says David Bastviken, professor at Tema Environmental Change, Linköping University.

This means that warming will be faster than expected from anthropogenic greenhouse gas emissions alone. According to Professor Bastviken this also means that any reductions in anthropogenic greenhouse emissions is a double victory, by both reducing the direct effect on warming, but also by preventing the feedback with increased natural emissions. 

More information: Sivakiruthika Natchimuthu et al. Spatio-temporal variability of lake CH fluxes and its influence on annual whole lake emission estimates , Limnology and Oceanography (2015). DOI: 10.1002/lno.10222

H. Marotta et al. Greenhouse gas production in low-latitude lake sediments responds strongly to warming, Nature Climate Change (2014). DOI: 10.1038/nclimate2222

Sivakiruthika Natchimuthu et al. Influence of weather variables on methane and carbon dioxide flux from a shallow pond, Biogeochemistry (2014). DOI: 10.1007/s10533-014-9976-z

Balathandayuthabani Panneer Selvam et al. Methane and carbon dioxide emissions from inland waters in India - implications for large scale greenhouse gas balances, Global Change Biology (2014). DOI: 10.1111/gcb.12575

E. J. Lundin et al. Large difference in carbon emission - burial balances between boreal and arctic lakes, Scientific Reports (2015). DOI: 10.1038/srep14248

Martin Wik et al. Energy input is primary controller of methane bubbling in subarctic lakes, Geophysical Research Letters (2014). DOI: 10.1002/2013GL058510 

Carbon Capture: key green technology shackled by costs

Every credible plan to save humanity from global warming reserves a key role for a green energy technology called carbon capture and storage. 

But there's a problem: no one has figured out a viable way to pay for it. 

Usually just called CCS, the technology can take carbon dioxide - the dominant greenhouse gas - from major pollution sources such as power plants or steel mills and pump it deep underground, out of harm's way.

CCS is crucial to many scenarios - including from the United Nation's climate science panel - for keeping global warming under 2 degrees Celsius (3.6 degrees Fahrenheit), considered the red line for catastrophic climate impacts. 

But despite decades of testing, only a handful of the projects are actually in service. 

One of the main reasons, experts say, is a very hefty price tag that has kept nervous investors at bay.

"There are 22 large-scale (CCS) operations in the world," said Isabelle Czernichowski-Lauriol, president emeritus of CO2GeoNet, a European research network. 

"We need to have over 1,000," she told AFP. 

"There has been a delay in regards to what was expected, but it has mostly been due to the lack of an economic model."

Catching, transporting and storing just a fraction of the world's carbon emissions would require the construction of a massive new industry.

'Cost is main barrier'

CCS works by compressing a gas, CO2, into a liquid form and pumping it into the ground.

Scientist and analyst Vaclav Smil, a respected voice on environmental and energy matters, has calculated that a CCS infrastructure - to capture and store 20 percent of the world's CO2 from burning fossil fuels - would need a capacity 70 percent larger than the petroleum flow handled by the global crude oil industry.

The scale of effort needed for any substantial reduction of emissions and the operating costs "combine to guarantee very slow progress," he wrote.

At the moment, Canada's Boundary Dam power station in Saskatchewan is the world's only commercial-scale coal-fired power plant that uses carbon capture to keep its emissions out of the air.

It is designed to grab 90 percent of the plant's CO2 gases - the equivalent of the pollution from 250,000 cars - which are then sold and pumped to nearby facilities for use in squeezing oil out of the ground.

Sale of the gas provides extra revenue for the station, which cost 1.5 billion Canadian dollars (one billion euros) to build. About a sixth came from government subsidies. 

"Cost is one of the main barriers to CCS," said Samuela Bassi, a policy analyst at the London School of Economics and Political Science. "Building these plants is expensive."

Adding carbon capture technology to coal-fired power plants pushes up their cost by 40-80 percent, and by up to 50 percent for natural gas-burning stations.

Dearth of projects

One reason carbon capture is so expensive is the technology is relatively new as a climate change solution - about a decade old - and some of the projects are one-of-a-kind.

A developing technology without a proven, viable business model is also seen as risky by investors, driving up the cost of borrowing money, analysts said. 

Further handicapping CCS, a lot of government subsidies - and regulatory support - are going to competing technologies such as wind and solar.

"For CCS you don't yet have this type of system in place, except in the UK," said Bassi. "But in the rest of the world you don't have that kind of economic support."

Analysts say the cost of CCS-equipped power plants will come down significantly as more projects get built and the technology is refined.

However, just two carbon capture-equipped, industrial-scale power plants - both in the United States - are due to come online next year, and there are a dearth of big projects on the drawing board.

There are 22 large-scale CCS projects that are either in operation or are slated to be up and running by 2017.

Another 23 big projects currently in various stages of development are "maybes", according to a spokesman for the Global Carbon Capture and Storage Institute, an industry group.

That total number of industrial-scale projects - 45 - is an 18-percent decrease over the 55 listed in the institute's 2014 report. 

EU targets have called for the equivalent of 11 large-scale, CCS-equipped power plants by 2030, which would cost up to 35 billion euros ($40 billion), according to the Grantham Research Institute on Climate Change and the Environment.

So far 1.3 billion euros in public funds have been, or are being, spent on developing these projects.