The latest piece of alarmist climate pseudoscience is Understanding climate change from a global analysis of city analogues, published in PLOS ONE by a large team from Thomas Crowther’s lab in Zürich. His name may be familiar, as he was one the authors of what Geoff described as the World’s Worst Scientific Paper, the feeble smear job on Susan Crockford. Here’s the abstract, kicking off with a blatant call for political action:
Combating climate change requires unified action across all sectors of society. However, this collective action is precluded by the ‘consensus gap’ between scientific knowledge and public opinion. Here, we test the extent to which the iconic cities around the world are likely to shift in response to climate change. By analyzing city pairs for 520 major cities of the world, we test if their climate in 2050 will resemble more closely to their own current climate conditions or to the current conditions of other cities in different bioclimatic regions. Even under an optimistic climate scenario (RCP 4.5), we found that 77% of future cities are very likely to experience a climate that is closer to that of another existing city than to its own current climate. In addition, 22% of cities will experience climate conditions that are not currently experienced by any existing major cities. As a general trend, we found that all the cities tend to shift towards the sub-tropics, with cities from the Northern hemisphere shifting to warmer conditions, on average ~1000 km south (velocity ~20 km.year-1), and cities from the tropics shifting to drier conditions. We notably predict that Madrid’s climate in 2050 will resemble Marrakech’s climate today, Stockholm will resemble Budapest, London to Barcelona, Moscow to Sofia, Seattle to San Francisco, Tokyo to Changsha. Our approach illustrates how complex climate data can be packaged to provide tangible information. The global assessment of city analogues can facilitate the understanding of climate change at a global level but also help land managers and city planners to visualize the climate futures of their respective cities, which can facilitate effective decision-making in response to on-going climate change.
So these people are making the ridiculous claim that the climate in London in 2050 will be like that in Barcelona today. A quick google check show that summer max/min in London is about 23/15°C while Barcelona is 29/23°C, so these charlatans are claiming that we are going to have 6 or 8 degrees of warming in the next 30 years. Worse still, they claim that this is under the moderate RCP 4.5 scenario. RCP 4.5, according the IPCC, gives a warming of 1.1°C to 2.6°C over a century, but Crowther and his team are claiming three times that in 30 years, in other words they seem to be exaggerating by a factor of about 10.
But what does “today” mean? Well, you might think it means today, but apparently not. In parentheses inside the paper, “today” is defined as meaning an average over the period 1970-2000, centred on 1985. So the “today” that they are talking about is 34 years in the past, further away than the 30 years into the future that they are trying to predict! The same people have a glossy web site promoting their alarmist bullshit, presumably aimed at the public, which uses “today” without explaining what that means. This has fooled the Guardian’s useful idiot Fiona Harvey, who starts her article with “London will have a similar climate in three decades’ time to that of Barcelona today, according to research”.
To see what a dishonest pack of lies this paper is, it’s interesting to look at what has happened over the last 30 years. Coincidentally, Paul Homewood has a blog post today that does just that, pointing out that “temperatures in Britain have been stable for the last three decades”. I checked the Central England Temperature data over the last 30 years and it looks like this:
Nothing at all has happened over the last 30 years, as Paul Homewood says. Of course, Central England is not the same thing as London, but London isn’t greatly different. The only London weather station in the GISTEMP system is Heathrow – climate scientists love measuring historical temperatures at expanding airports – which shows a warming of roughly half a degree.
So whether “today” means today or 30 years ago, Thomas Crowther and his fellow con-artists are claiming that we are going to see about 6 degrees of warming over the next 30 years, when we’ve seen virtually none in the last 30. That’s 0.2 degrees per year, about 10 times the current global rate of warming.
This is also how the Guardian article interprets it. A graphic labelled “London’s climate in 2050 could be similar to Barcelona’s climate now” has London marked with an absurdly precise +5.9. As usual, anyone hoping that there might be an honest climate scientist prepared to call out this bullshit would be very disappointed. In fact it’s worse than that. Richard Betts (currently in Kathmandu at an IPCC meeting), who I used to regard as an honest man, at least by the standards of climate scientists, is quoted in the article wondering whether we will be able to adapt. No Richard, the question doesn’t even arise, because the claim of 6 degrees of warming over the next 30 years is total crap, as you know perfectly well, but don’t have the integrity to admit. Worse still, he is promoting the Guardian article via his pinned tweet. He doesn’t seem at all concerned that the article misleads the public from its first sentence.