Global warming brings wild weather


Just over a month ago I wrote about Australia’s Warmest Year On Record and ended the post by saying:

None of the above is necessarily due to global warming but it is all entirely consistent with global warming, and we can expect that weather like this will become normal as global warming progresses. Bearing in mind that this year represents, as the BoM says, temperatures [only] 1.2 C* above the baseline and medium-term predictions are in the range of  2 – 6 C above the baseline, I think we should be more worried than most of us are; but I will deal with those issues on their own in another post as soon as I can find time.

*That 1.2 C was Australia’s land surface temperature deviation. We out-did ourselves last year and in doing so we out-did the rest of the world, which is why the global average deviation (see below) is only half as large.

Now seems to be the time to look at those looming problems, while extreme weather around the world is dominating our evening news:

And don’t forget that an extreme event doesn’t end when the weather eases – remember  Typhoon Haiyan recovery effort to take up to five years and, locally, Bushfire recovery in the Blue Mountains stalls.

James Hansen, one of the world’s leading climate scientists, told us a few years ago that global warming was “loading the climate dice”, making extreme weather events much more common (quick introduction / technical introduction), and this is what we are seeing now. The bad news is that people are suffering the effects of climate change earlier than they would have done if this amplification of extreme weather had not occurred; its silver lining is that the extreme events are encouraging their victims to sit up and take notice and (hopefully) take action on the underlying problem earlier than they would otherwise have done.

I’m not the only person to have noticed this, of course. Al Gore’s recent comments on the subject, for instance, have been widely shared. The Guardian (rapidly becoming one of my more-trusted news sources, by the way) reported him thus:

Extreme weather events including typhoon Haiyan and superstorm Sandy are proving a “gamechanger” for public awareness of the threat posed by climate change, Al Gore said on Friday.

The former US vice-president, speaking to delegates at the World Economic Forum in Davos, said: “I think that these extreme weather events which are now a hundred times more common than 30 years ago are really waking people’s awareness all over the world [on climate change], and I think that is a gamechanger. It comes about, of course, because we continue to put 90 million tonnes of global warming pollution into the atmosphere every day, as if it’s an open sewer.”

But he said the falling price of solar and wind power gave hope for efforts to tackle climate change.

“There’s a second gamechanger, that is that the cost down-curve for photovoltaic electricity and, to a lesser extent, wind. In 13 countries, the price of solar is cheaper than or equal to the [electricity] grid average price.” He claimed that within a decade most people would live in regions where that was true, and said of the falling costs of the technologies: “It is very impressive and it is opening up great opportunities for the world to solve climate change.”

Gore’s presentation at Davos was also covered on Mashable, under the heading Al Gore on Climate Change: ‘Extreme Weather Events Are a Game Changer’.

Meanwhile, Lord Nicholas Stern (of the 2006 Stern Report) made similar points on the front page of The Guardian and attracted valuable commentary from Joe Romm on Climate Progress at In Flooded UK, Guardian Warns ‘Climate Change Is Here Now’.

There are, I think, two take-home messages from all of the above (1) we must all be prepared for wild weather from here into the foreseeable future and (2) if this weather is what we get from an average global temperature just 0.6 – 0.7 C above the twentieth-century average, a 2C rise is not going to be “safe enough” by any reasonable interpretation.

Extreme weather around the world

For a while now the climate scientists have been warning that global warming isn’t simply a matter of the weather getting a little warmer everywhere. Rather, the warming will vary from place to place and be accompanied by changes of weather patterns, especially rainfall. That is already happening. I have mentioned extreme weather events here before over the last year or so, and in fact the last few months have seen a cluster of extreme events which are causing great suffering across the Northern hemisphere.

We know that none of these can be ascribed to climate change with any certainty but there is a growing body of knowledge (e.g. IPCC, Climate Communication) which shows that we can confidently give the odds that a particular event would have happened without global warming, and the experts are quoting high odds against any of these happening under our old weather patterns. The combined odds against all of them happening by chance are infinitesimal.

The silver lining to this litany of disaster is that ordinary people are beginning to see for themselves that weird things are happening to their weather and are more willing to acknowledge that climate change is indeed here already, that it is looking scarier every year, and that we really should try harder to avert it.

Smile: In what seems like poetic environmental justice, a brown coal mine in Victoria’s Latrobe Valley has also been flooded after unusually heavy rain.

Don’t smile too broadly: James Hansen, one of the world’s pre-eminent climatologists, has warned that the future he predicted is here here already and it is worse than he expected, sooner than he expected – almost entirely because of extreme weather events:

In a new analysis of the past six decades of global temperatures, which will be published Monday, my colleagues and I have revealed a stunning increase in the frequency of extremely hot summers, with deeply troubling ramifications for not only our future but also for our present.

This is not a climate model or a prediction but actual observations of weather events and temperatures that have happened. Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change. To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.

The rest of his Washington Post article is here and if you want the whole scientific  paper you can get it – free – here.