Heatwaves 'impossible' without climate change

Southern European countries usually experience high temperatures in July and August - which is part of the reason they attract so many holiday-makers. But this year those temperatures have gone far beyond their previous limits, and now wildfires are causing havoc in parts of Greece and Italy. Experts say the latest searing heatwave would have been “virtually impossible” without climate change. The UK’s Met Office has also warned that record-temperatures will soon become the norm. Sir Bob Watson is a physical chemist specialising in environmental science and a leading authority on the science of climate change…

Bob - It would be very, very unlikely to occur without human induced climate change. It's not only the heat waves in Europe, but in China, in the southwest of the United States. And the scientists that are looking at these issues do state categorically that without human induced climate change, we would not be seeing these extreme events. And indeed, it's not just heat waves. We're seeing more floods, we're seeing more drought, we are drying our land, which leads to more forest fires. So yes, human induced climate change is certainly linked to these phenomena.

Chris - So it's the pattern that is telling here, because of course we've always had record breaking temperatures in the past, haven't we? We've had one-offs, but it's the consistency and the geographical pattern.

Bob - Yeah. I mean, what we're seeing this year is not only these heat waves, in fact, what we've seen is the hottest day globally. We've now seen the hottest June ever. We've seen the Atlantic Ocean being warmer than ever for this time of year. And we've seen record low amounts of Antarctic sea ice. We've seen all of the patterns that we would expect with human induced climate change. We've always stated that a change caused by humans would lead to more extreme events. And this is what we're seeing.

Chris - And in the near term, what do you think is in store for the tourist industry? Are we going to see more of this and, and should people effectively plan that those sorts of summer holidays might in future be off limits?

Bob - It is not just the summer in the winter within the snow falling later and melting earlier. So the ski resorts in Europe, North America are also threatened by human induced climate change. But you are right. If we start to see as a new normal, these high temperatures in June, July, it would make people want to have more vacations in the spring and in the fall. But of course, children's school holidays are in the middle of summer. Maybe that has to change in the future.

Chris - People often liken the climate to an oil tanker steaming along the sea. As in, there's enormous momentum in the system. So even if you stop the tanker's engines, it's going to roll on for quite some distance before it comes to a halt. So how much worse then is this going to get, even if we go as planned and we aggressively cut down carbon emissions?

Bob - Well, the problem is that the governments that signed the so-called Paris Climate Agreement to try and limit human induced climate change to no more than two degrees Celsius and preferably 1.5 degrees Celsius, the pledges these governments have made are not putting us on a pathway to 1.5 or two. They're putting us on a pathway for the world to warm 2.5 to possibly three degrees Celsius. If we want to be on a pathway of one and a half to two, we need global emissions to be 50% lower by 2030 than they were in 2020. And the trouble is the emissions are going up still. They're not going down.

Chris - Do you think that to an extent there's a messaging problem? Because when we say things like one and a half degrees or two and a half degrees, that doesn't sound like very much. I mean, that's obviously a global average. So in global terms, it's huge because there are going to be extremes at each end to reach that average. But do you think we should start telling people, look at what's happening in places like Southern Europe at the moment and that would focus their minds a bit more?

Bob - Oh, I think we have to improve our messaging. What we should tell people is globally averaged. We've only warmed about 1.2 degrees Celsius since pre-industrial times. And look what we're seeing. If we go to two degrees, let alone three degrees, we're going to see even more of these three extreme weather. We'll see sea level rise causing coastal erosion, people being moved from their homes. So I do think we have to relate what does 1.5 or two or 2.5 really mean?

Chris - One problem though is that with cutting carbon comes a cost to be paid. And many people in the UK are struggling to pay their bills at the moment, and they're being told to install heat pumps costing enormous amounts of money. They're being told they won't be able to buy a gas boiler from a certain date. They're being told they'll have to invest in an electric new car rather than a petrol and diesel one. The UK's contribution to global emissions is about 1%. And many other countries totally eclipse our contributions. So I don't want to use a rude expression, but are we urinating into the wind?

Bob - All countries have to cut their emissions, especially countries that have had high emissions in the past, which are the developed industrialised countries of North America, Europe, Russia, et cetera. We all have to do our part. And there's no question there will be some short term costs, but to be honest, in the long term, it will cost all of us less money to avoid climate change than to adapt to climate change. So we do need to make these changes, but the government has to work with the public to try and make these changes as painless as possible.

Chris - The point I was making though, is that we could bend over backwards in this country and have no carbon emissions at all by working very hard at it. And we would make such a slim dent if everyone else continues the way they're going, that really it would be not worth doing it.

Bob - Absolutely correct. We're all in this together. That's why the Paris Agreement was such an important agreement, and that every country in the world literally said, we will try and achieve these targets, but we need the big emitters. China, the United States, India, the UK alone, zero in its emissions will make very little difference. So there must be an international agreement where we all work together. We're basically all in the same lifeboat. We'll either all sink together or we'll swim together.