Climate Scientists Say The Dice Are Loaded. Here's Why

[00:00:00]Well, it’s summertime here in the northern  hemisphere folks, and that means the usual round of unqualified rhetoric from both sides of  what some people refer to as a debate about the global climate. On the one hand you have  the extreme doomers who latch onto every heatwave as a portent of a dystopian Mad Max  style future, and vindication of everything they’ve been warning us about for years. On the  other hand, you’ve got the climate sceptics and, dare I say it in this day and age, even still  a few climate DENIERS, who helpfully point out that the seasons are a perfectly natural aspect  of life on earth and that the weather always gets hot in the Summer and we should all stop  being so woke and just calm down and get real.

[00:00:39]And as usual somewhere in the middle of  that cacophony of online social media noise, the actual scientists are holding their little  hands up and offering to provide a data driven assessment based on empirical evidence  and sophisticated climate modelling…and generally speaking getting completely drowned  out by all the other more contentious and more exciting content doing the rounds. So, let’ see if we can tease that science out from all the bluster and  blow and have a little look at it.

[00:01:11]Hello and welcome to Just Have a Think. I think we’ll start here in good old blighty.

[00:01:16]Now for those who don’t live in the UK, we  have this very famous yard stick by which, for the last fifty years, we’ve been sort of  gauging our warmer summers. That yard stick was the summer of nineteen seventy-six. I remember  it well. I remember a wonderful family vacation in Cornwall and hoping the lovely hot weather would  never end. It was undoubtedly a freak summer, with temperatures nudging up to thirty degrees  Celsius, or eighty-six Fahrenheit where we were, which was a temperature that, at the age  of seven, I didn’t even know existed!

[00:01:45]In fact, the town of Cheltenham achieved a high  of thirty-five point-nine Celsius or nearly ninety-seven degrees Fahrenheit that year. It  was all very exotic for our windy little island.

[00:01:55]Anyway, the point is, since that summer, and  particularly in recent years, whenever we’ve had a heatwave here in Britain, the sceptical  types have always said “well, it’s no different to nineteen-seventy-six. These freak summers come  along every now and then. It’s perfectly normal.”

[00:02:09]In fact, if you look at these two heat maps,  you might reasonably agree with that assessment.

[00:02:14]They’re available on the climate lab book website,  produced by Professor Ed Hawkins, who is a climate scientist at the University of Reading, best  known for creating the iconic "climate stripes" graphic that visualises the long-term warming of  the planet using a simple sequence of coloured bands. The colours in these maps show the average  temperature relative to the nineteen-sixty-one to nineteen-ninety average. White is neutral,  blues are colder than the average and reds are warmer than the average, with darker reds being  significantly warmer than average. So, if you only looked at these maps, you might be forgiven  for thinking the UK was actually cooler in twenty-four than it was in nineteen-seventy-six. But then Ed zooms out a bit to look at the same two years across Europe. What that shows us  is that there really was a bit of a freak weather system sitting on top of the UK in  seventy-six that was affecting only a small part of the rest of the continent. By contrast, in  twenty-twenty-four, the continental land mass was sweltering while we only got a small taste of the  heat in the south-east of our country. But for my money, you only really get the real perspective  on the nineteen-seventy-six UK heatwave when you zoom fully out to have a look at the  entire planet. What this tells us is that the overwhelming majority of the planet was  close to or below the nineteen-sixty-one to nineteen-ninety average back then. You can  barely see our little heatwave in the UK.

[00:03:32]It was really nothing more than a statistical  anomaly. Now compare that to the global map in twenty-twenty-four. That’s not a localised freak  weather event. That’s an entire planet that is warmer or much warmer than the baseline period. But, again, you can’t judge the whole picture just by one season of one year,  can you? Quite right. You can’t.

[00:03:53]So, let’s try some analysis from the  World Weather Attribution website.

[00:03:57]They found that the record temperatures  Britain has experienced in the last few weeks would have been extremely unlikely in  the climate of the 1970s. They calculated that similar meteorological conditions back then  would have resulted in daytime temperatures about three-point-five degrees Celsius  cooler than those we’ve seen this year.

[00:04:16]Why? Well because the entire global climate  system is carrying more heat energy now than it was back then, so when a heatwave  does come along, it packs a bigger punch.

[00:04:25]It’s also worth noting that Europe is  warming up twice as fast as the global average. Zero-point-five-six degrees  Celsius per decade to be precise.

[00:04:33]Again why? Well, Europe is a big old land  mass, and land heats up much more quickly than water. Continental Europe just doesn’t  get the benefit of ocean heat absorption in the way that other parts of the world do. Plus,  northern Europe is connected the fastest warming region on earth – the Arctic, which thanks to  Sea Ice loss and the feedback loop of reducing albedo or reflectiveness, is now warming at about  zero-point seven-five degrees Celsius per decade, which is THREE times the global average. Europe has also done a great job of clearing up its air pollution in recent decades.  But removing those particulates means removing some of the reflective aerosols that had  previously masked part of the greenhouse warming.

[00:05:15]Plus, according to the Copernicus Climate Change  Service, Europe has also experienced changes in large-scale weather patterns that favour  stronger blocking high-pressure systems, longer-lasting heat domes, more hot air  transported north from North Africa and fewer cooling Atlantic weather systems during summer.  Those patterns don't create global warming, but they do make European summers much  more prone to prolonged heatwaves.

[00:05:40]We also have drying soils on this continent,  which means much less incoming solar radiation gets used for evaporation. Instead, more  energy goes directly into heating the ground and the air. That creates a feedback  loop. Hotter weather dries the soil. Dry soils make subsequent hot weather even hotter and  therefore heatwaves become more and more intense.

[00:06:00]The famous US climate scientist James  Hansen calls it “loading the heat dice”.

[00:06:05]It’s a phrase that was illustrated beautifully  by John Lang, a UCL graduate in Earth Science, Trade Law and Environmental Policy and the founder  of an education program called Climate Trunk.

[00:06:16]So, each of these grey squares represents a  year, and we’ve got a hundred of them here, so that ‘s a century. So far so good. Using  historical data, we can plot how often a once in fifty-year heatwave happened in pre-industrial  times, which is the baseline for this graphic.

[00:06:31]Clearly, back then a once in fifty-year heatwave  would happen twice in a century. So, let’s fill in a couple of squares in red to represent that. Lovely.

[00:06:41]Now let’s see what happens at an  average global surface temperature of one-point-five degrees Celsius above those  pre-industrial times, which is roughly where we’re at today. It’s quite a lot more heatwaves, don’t  you think? In fact, at current temperatures a once in fifty-year heatwave will statistically occur  SEVENTEEN times during the course of a century.

[00:07:00]You probably don’t need me to tell you that  heatwaves cause major damage to infrastructure, productivity and human health, so a  reasonable person would surely say we want to avoid nudging ourselves up to  TWO degrees above pre-industrial times.

[00:07:15]But according to a twenty-twenty-five study by  the Potsdam Institute for Climate Impact Research, our current trajectory gives us a twenty percent  probability of reaching that level as early as twenty-forty-seven and an EIGHTY percent  chance of reaching it by twenty-sixty-nine.

[00:07:29]At that temperature level we’re looking at  twenty-eight ‘once-in-fifty-year’ heatwaves in a typical century. That’s more than one every  four years, which leaves precious little time to recover and rebuild from one heatwave  before getting clobbered by another one.

[00:07:43]The recent so-called Scenario Model  Intercomparison Project for CMIP7 paper that we looked at in a recent video, revises  the existing IPCC scenarios down a bit, to take account of the progress made on  emissions reductions since those scenarios were first published more than fifteen years ago.  Nevertheless, the draft CMIP7 scenario framework suggests that under its central emissions  pathway, global temperatures could approach four degrees Celsius sometime during the second  half of the next century. Now, at that level, what we used to call a once in fifty-year  heatwave would be more or less a normal year. And what would be called a heatwave  then would be absolutely unthinkable today.

[00:08:24]Of course, you folks in the United States have  also been experiencing your own heat dome in recent weeks, so you’re not in the clear by any  means. And although it’s wintertime down under, Australia’s climate is becoming ever  more brutal as each year goes by. So, we really do have a global problem here. The folks at Bloomberg published their own analysis very recently, providing us  with some quite sobering statistics.

[00:08:47]They point out that September twenty-twenty-three  was 8:56 half a degree Celsius hotter than the previous September record. Apparently, that’s “the biggest such margin ever and extreme even for an El Niño year.” The rate of temperature change has increased in recent years too, which is  something we looked at in a recent video.

[00:09:07]Earth’s energy imbalance, which  is the gap between incoming energy and heat radiated back out to space, has  roughly doubled over the past two decades.

[00:09:17]“There were four times as many new heat records  set from 2016 to 2024 as there would have been without climate change” says the analysis Physics tells us that for every degree Celsius of warming, our atmosphere can  hold onto seven percent more moisture.

[00:09:32]As a result, record rainfall levels are  happening forty percent more often than they would without our current warming, while record  dry spells are hitting us ten percent more often.

[00:09:43]Melted ice sliding off of land masses now accounts  for more than half of observed sea-level rise and the rate of ice loss observed during 2006–2025 was  more than twice that measured during 1976–1990.

[00:09:58]Thermal expansion is doing the rest of  the job as our oceans reach levels of warming never before recorded, which  by the way is completely disrupting the geographical habitats and migration  patterns of all sorts of marine life, not to mention killing off a good chunk of  essential coral ecosystems. And of course, the warmer seas are nibbling away at the  floating ice shelves that buttress the West Antarctic Ice Sheet, which was the subject  of another recent video on this channel.

[00:10:25]I’m not going to prattle on about all the  consequences of these changes. I’ve made countless videos about that in the past. Suffice  to say, none of those consequences is good.

[00:10:34]In fact, I’m not going to waste your time with  any kind of concluding remarks at all. If you can’t see the blindingly obvious with your  own eyes, then I’m afraid I can’t help you.

[00:10:44]By all means leave your thoughts in the  comments section below and as always, I will read as many of them as time allows. That’ll do us though. I couldn’t make any of these videos without the monthly support  of very generous individuals who support me on a monthly basis over on the Patreon  platform, so a massive shout out to those fantastic people who also enable me to keep  ads and sponsorship messages out of your way.

[00:11:09]Do give us a like and subscribe if you want to see  more content like this. And most important of all, thanks very much for watching. Have a great week if you can.

[00:11:19]And remember to Just Have a Think. See you next week,