Has the weather gone weird? And if so, is it because of climate change? We’ve had the wettest June in over a century and as the rain buckets down these are popular questions. But are there any good answers?
One definition of climate is ‘the average of weather’, so if the climate changes, there’s going to be an effect on weather patterns. The IPCC concluded last year that “climate change has led to changes in climate extremes such as heat waves, record high temperatures and, in many regions, heavy precipitation in the past half century”.
But what the media really want to know is whether climate change caused this rain now, and today Radio 5 felt moved to devote a dismal phone-in to the question, featuring a fairly even mix of green campaigners, climate sceptics and confused members of the public – although no climate scientists.
The media discuss the climate/weather link
Aside from Radio 5’s rather daft approach, there have been some more informative efforts. In the Telegraph Michael Hanlon asks ” What is going on with the weather?”:
“There will, inevitably, be suggestions that the current soggy weather might have something to do with climate change. It is hard to say for sure, but the answer is that it probably doesn’t. Predicting the impact of rising temperatures in Britain is difficult because we are sandwiched between the competing air masses of Eurasia and the Atlantic.”
The UK probably won’t be spared some wild weather if the temperature continues to change in the future – but this is different to discussing the current weather, he points out.
On the other hand, The Mirror’s weatherman Bill Giles is feeling considerably more confident than most scientists, saying that the awful weather is the fault of “[putting] a lot of carbon gases into the atmosphere.”
Meanwhile in the Express, a lack of sunlight appears to have driven Adam Lee-Potter to febrile Old Testament-style prophecy. He confesses: “Though I’m not a religious man, it is hard not to read biblical inference into this time of black skies, sly bankers and fiscal collapse”.
If predicting the end of days wasn’t enough evidence that the weather is having a deleterious effect on the press’s state of mind, a Times editorial yesterday seals the deal. It suggests the appropriate response is geoengineering. We could stop it raining, the Times suggests, by seeding clouds using silver iodide particles sprayed from an aeroplane.
Wishful thinking? Bear in mind that Rupert Murdoch almost certainly has the cash to pull it off. Would geoengineering back the British summer win him the forgiveness of a grateful nation?
Pro-tip: Ask a scientist
Most of the media coverage – like Hanlon’s piece – has been pretty cautious in linking the rain to climate change, tallying with many scientists’ caution about putting single weather events down to climate change.
The best reporting has come when journalists give scientists space to discuss the area in detail. The Met Office discussed the possible link between unsettled weather and climate change with the Guardian:
“…record wet conditions, which have brought serious flooding to regions from Yorkshire to the south-west, were owing to “a particularly disturbed jet stream” … Some research has suggested that the massive melting of Arctic ice has been responsible for this effect – by changing the patterns of warmer and colder winds in the upper atmosphere. But the key question – of whether man-made global warming is putting a dampener on British summers – will take several years to solve…”
While Dr Peter Stott told the Telegraph:
“There has been a four per cent increase in moisture over the oceans since the 1970s,” he said. “Therefore there is potential for periods of heavy rain to be more extreme.”
…as he also warned against looking for overly simple answers:
“…in some regions, weather patterns as a whole could change due to natural as well as human causes. For example, if there were a systematic shift in the jet stream, the fast flowing ribbon of air high in the atmosphere that steers storm systems, this could reduce the risk of extreme rainfall in some places.”
We probably shouldn’t expect a definitive answer at this stage. Recent studies that have suggested extreme weather has changed the probabilities of particular weather events have taken up to a decade to be published in the scientific literature – and even then talk in terms of changed probabilities, rather than straightforward ’caused by’ relationships.
The difficulty of attributing a single weather event doesn’t undermine confidence in wider predictions of a more extreme climate as the planet warms. Stott concludes:
“While it is clear that across the globe there has been an increase in the frequency of extreme heatwaves and of episodes of heavy rainfall, this does not mean that human-induced climate change is to blame for every instance of such damaging weather. However climate change could be changing the odds and it is becoming increasingly clear that it is doing so in such a way as to increase the chances of extremely warm temperatures and reduce the chances of extremely cold temperatures in many places.”
In summary, attributing particular events is hard or impossible at the moment. That’s not the same as saying that climate change doesn’t affect the weather. With four per cent more water in the atmosphere over the oceans, as the BBC put it – “what goes up must come down“.
If you’re planning a weekend camping in Dorset or perhaps a Radio 5 phone-in, that might be an unsatisfactory answer. But it might be the best you’re going to get for the moment.