• Damian Carrington
• theguardian.com, Tuesday 12 August 2014 06.59 AEST
• Jump to comments (73)

Extreme weather like the drought currently scorching the western US and the devastating floods in Pakistan in 2010 is becoming much more common, according to new scientific research.

The work shows so-called “blocking patterns”, where hot or wet weather remains stuck over a region for weeks causing heatwaves or floods, have more than doubled in summers over the last decade. The new study may also demonstrate a link between the UK’s recent flood-drenched winter and climate change.

Climate scientists in Germany noticed that since 2000 there have been an “exceptional number of summer weather extremes, some causing massive damage to society”. So they examined the huge meanders in the high-level jet stream winds that dominate the weather at mid-latitudes, by analysing 35 years of wind data amassed from satellites, ships, weather stations and meteorological balloons. They found that blocking patterns, which occur when these meanders slow down, have happened far more frequently.

“Since 2000, we have seen a cluster of these events. When these high-altitude waves become quasi-stationary, then we see more extreme weather at the surface,” said Dr Dim Coumou, at the Potsdam Institute for Climate Impact Research. “It is especially noticeable for heat extremes.” The intense heatwaves in Russia in 2010, which saw 50,000 people die and the wheat harvest hit hard, and in western Europe in 2003, which saw 30,000 deaths, were both the result of blocking patterns. The Intergovernmental Panel on Climate Change concluded in 2011 that extreme weather would become more common as global warming heats the planet, causing both heatwaves and increasingly severe rain storms.

The rise in blocking patterns correlates closely with the extra heating being delivered to the Arctic by climate change, according to the research which is published in the journal Proceedings of the National Academies of Science (PNAS). Coumou and his colleagues argue there are good physical reasons to think there is a causal link, because the jet streams are driven by the difference in temperature between the poles and the equator. As the Arctic is warming more quickly than lower latitudes, that temperature difference is declining, providing less energy for the jet stream and its meanders, which are called Rossby waves.

Prof Ted Shepherd, a climate scientist at the University of Reading, UK, but not involved in the work, said the link between blocking patterns and extreme weather was very well established. He added that the increasing frequency shown in the new work indicated climate change could bring rapid and dramatic changes to weather, on top of a gradual heating of the planet. “Circulation changes can have much more non-linear effects. They may do nothing for a while, then there might be some kind of regime change.”

Shepherd said linking the rise in blocking events to Arctic warming remained “a bit speculative” at this stage, in particular because the difference between temperatures at the poles and equator is most pronounced in winter, not summer. But he noted that the succession of storms that caused England’s wettest winter in 250 years was a “very good example” of blocking patterns causing extreme weather during the coldest season. “The jet stream was stuck in one position for a long period, so a whole series of storms passed over England,” he said.

Coumou acknowledges his study shows a correlation – not causation – between more frequent summer blocking patterns and Arctic warming. “To show causality, computer modelling studies are needed, but it is questionable how well current climate models can capture these effects,” he said.

Prof Tim Palmer, at the University of Oxford, wrote in a PNAS article in 2013 that understanding changes to blocking patterns may well be the key to understanding changes in extreme weather, and therefore to understanding the worst impacts of climate change on society. But he said climate models might have to run down to scales of 1km to do so. “Currently, national climate institutes do not have the high-performance computing capability to simulate climate with 20km resolution, let alone 1km,” he wrote. “[I] look forward to the day when governments make the same investment in climate prediction as they have made in finding the Higgs boson.”

Coal bed methane: sorting the information from misinformation

Sam Dodson looks to sieve through the reams of misrepresented facts and misinformation in the hunt for accurate data on the benefits – or otherwise – of coalbed methane.

A recently published report in the Proceedings of the National Academy of Sciences (PNAS) in the US has extolled some of the benefits of coalbed methane (CBM) and other unconventional resources, while also noting the need for further study to determine both the benefits and risks associated with developing such fuel sources.

The report has been held up by industry lobbyists as a sign of the potential benefits of CBM: for example, the report noted that CBM would release “half the CO₂ of coal”.  Meanwhile, activists pitted against the development of unconventionals have either refuted the report or drawn attention to its stance that further study into the industry is needed.

Both groups would look to sway public opinion to their own way of thinking and, as such, choose to grasp at and support any report or news development that would appear to back up their claims, regardless of how accurate any such thing may be.

Indeed, there is a growing body of research showing that, when a person’s worldview is threatened by scientific evidence, they interpret the science in a biased manner. People choose the data that supports their views, or views of those closest to them, and place greater weight on evidence that confirms those beliefs, while ignoring or resisting conflicting evidence.

Mass communication and social media

With the advent of mass communication, activists and lobbyists are able to spread the evidence that supports their views with ease. Both groups will also respond to each other’s actions in kind: an industry lobby group posts an article extolling the benefits of CBM, and attacking those that refute such benefits; activists post information that claims the opposite is true.

As Michael Roche, CEO of Queensland Resources Council (QRC), at last year’s Coaltrans World Coal Conference in Berlin explained: “with so much of the world now connected and active on social media platforms,” it is easy to “hi-jack the good will of social media users and exploit this in order to spread a false message to serve [a group’s] own purpose.”

In a classic example of the way groups can spread disinformation, a number of activist “eco groups” spread false or doctored images that claim to show the negative effects of dredging and seaborne coal transport. Roche said that to believe this was in any way the case was entirely false, explaining that the coal and shipping industries have worked alongside reef authorities and their interaction with the Great Barrier Reef has been under close scrutiny for many years with no evidence that the industry does any damage. Roche also said it would not make sense for any industry professional to claim otherwise or do anything that in anyway endangered the reef: “We all have a vested interest in ensuring the reef continues to survive,” Roche said.

Roche, of course, has his own vested interest in supporting the coal industry – evidence indicates that the QRC receives AU$ 103 million from the coal industry to press the case for the state’s coal miners. Attacking the source of this income does not necessarily pay such rich dividends.

Another example, is the recent spat between the Australian Petroleum Production & Exploration Association (APPEA) and the Australian Medical Association (AMA). The AMA had recently suggested that natural gas from coal seams poses a risk to human health, a claim the APPEA accused of having more political overtones than scientific foundation. The AMA, in turn, argued that the opposite was the case.

Trying to find true, real and accurate information among all the misinformation can therefore be a significant challenge.

Fact and fiction

Alex Wonhas, from the Gas Industry Social and Environmental Research Alliance (GISERA), explains that: “deciding whether CBM is good or bad is wholly dependent on the individual’s definition of the words ‘good’ or ‘bad’.”

“It is in the interests of the industry to make you believe that CBM is good, while the opposite is true for other groups. The role of scientists and organisations such as the Commonwealth Scientific and Industrial Research Organisation (CSIRO) is to act as an honest broker and try to bring some clarity to the debate,” Wonhas adds.

CSIRO is currently set to investigate whether CBM activity is causing methane seeps in Queensland’s Surat Basin. The study will give authorities baseline data to compare over the life of the CBM industry. “We’ll be able to follow the eventual impacts on methane seeps to the atmosphere from these sources,” Dr Damian Barrett, Spokesman for Australia’s national science agency, said.

The project will be funded through a partnership between CSIRO and CBM companies operating in Australia.

It is through scientific research, such as that conducted by the CSIRO, as well as by gathering information in reports, such as the one released in the PNAS, that the information needed to ground our opinions in fact will be provided; rather than selectively choosing the misinformation generated by activists on both sides of the argument.

One thing else is clear: the world needs energy, yet the fact that human activity (including the creation of energy) effects climate change is almost universally accepted. A balance between these two pressing matters must therefore be struck – and struck quickly. As demand for power and electricity around the globe grows, energy production must increase. All sources of energy – from CBM and other unconventionals to mainstays like coal and gas, as well as renewables – must be considered as viable options in meeting energy needs until scientific fact proves otherwise. To spend time trying to win battles – be they with activists or lobbyists – to conjecture and form biased opinions over a subject as crucial to global development as energy resources is to only ever be on the losing side of an entirely bigger struggle.