it's really worth reading some of the things 00:18:00 that they're saying on climate change now and so what about 2 degrees C that's the 46th pathway that's the thousand Gigaton pathway the two degrees so you 00:18:13 look at the gap but between those two just an enormous that's where where no English edding we're all part of this and that's where we know we have to go from the science and that's where we keep telling other parts of the world begun to try to achieve the problem with 00:18:26 that and there's an engineer this is quite depressing in some respects is that this part at the beginning where we are now is too early for low-carbon supply you cannot build your way out of this with bits of engineering kit and 00:18:39 that is quite depressing because that leaves us with the social implications of what you have to do otherwise but I just want to test that assumption just think about this there's been a lot of discussion I don't know about within Iceland but in the UK quite a lot me 00:18:51 environmentalist have swapped over saying they think nuclear power is the answer or these one of the major answers to this and I'm I remain agnostic about nuclear power yeah it's very low carbon five to 15 grams of carbon dioxide per 00:19:03 kilowatt hour so it's it's similar to renewables and five to ten times lower than carbon capture and storage so nuclear power is very low carbon it has lots of other issues but it's a very low carbon but let's put a bit of 00:19:15 perspective on this we totally we consume in total about a hundred thousand ten watts hours of energy around the globe so just a very large amount of energy lots of energy for those of you I'm not familiar with these units global electricity consumption is 00:19:30 about 20,000 tarantella patelliday hours so 20% of lots of energy so that's our electricity nuclear provides about 11 a half percent of the electricity around the globe of what we consume of our 00:19:42 final energy consumption so that means nuclear provides about two-and-a-half percent of the global energy demand about two and a half percent that's from 435 nuclear power stations provide two 00:19:56 and a half percent of the world's energy demand if you wanted to provide 25% of the world's energy demand you'd probably need something in the region of three or four thousand new nuclear power stations to be built in the next 30 00:20:08 years three or four thousand new nuclear power stations to make a decent dent in our energy consumption and that assumes our energy consumptions remain static and it's not it's going up we're building 70 so just to put some sense 00:20:21 honest you hear this with every technology whether it's wind wave tidal CCS all these big bits of it technology these are going to solve the problem you cannot build them fast enough to get away from the fact that we're going to 00:20:34 blow our carbon budget and that's a really uncomfortable message because no one wants to hear that because the repercussions of that are that we have to reduce our energy demand so we have to reduce demand now now it is really 00:20:48 important the supply side I'm not saying it's not important it is essential but if we do not do something about the men we will not be able to hold to to probably even three degrees C and that's a global analysis and the iron would be 00:21:00 well we have signed up repeatedly on the basis of equity and when we say that we normally mean the poorer parts of the world would be allowed to we'll be able to peak their emissions later than we will be able to in the West that seems a 00:21:13 quite a fair thing that probably but no one would really argue I think against the idea of poor parts the world having a bit more time and space before they move off fossil fuels because there that links to their welfare to their improvements that use of energy now 00:21:27 let's imagine that the poor parts the world the non-oecd countries and I usually use the language of non annex 1 countries for those people who are familiar with that sort of IPCC language let's imagine that those parts of the 00:21:39 world including Indian China could peak their emissions by 2025 that is hugely challenging I think is just about doable if we show some examples in the West but I think it's just about past possible as 00:21:51 the emissions are going up significantly they could peak by 2025 before coming down and if we then started to get a reduction by say 2028 2029 2030 of 6 to 8 percent per annum which again is a 00:22:02 massive reduction rate that is a big challenge for poor parts of the world so I'm not letting them get away with anything here that's saying if they did all of that you can work out what carbon budget they would use up over the century and then you know what total carbon budget is for two degree 00:22:16 centigrade and you can say what's left for us the wealthy parts of the world that seems quite a fair way of looking at this and if you do it like that what's that mean for us that means we'd have to have and I'm redoing this it now 00:22:28 and I think it's really well above 10% because this is based on a paper in 2011 which was using data from 2009 to 10 so I think this number is probably been nearly 13 to 15 percent mark now but about 10 percent per annum reduction 00:22:40 rate in emissions year on year starting preferably yesterday that's a 40 percent reduction in our total emissions by 2018 just think their own lives could we reduce our emissions by 40 percent by 00:22:52 2018 I'm sure we could I'm sure we'll choose not to but sure we could do that but at 70 percent reduction by 2020 for 20-25 and basically would have to be pretty much zero carbon emissions not just from electricity from everything by 00:23:06 2030 or 2035 that sort of timeframe that just this that's just the simple blunt maths that comes out of the carbon budgets and very demanding reduction rates from poorer parts of the world now 00:23:19 these are radical emission reduction rates that we cannot you say you cannot build your way out or you have to do it with with how we consume our energy in the short term now that looks too difficult well what about four degrees six that's what you hear all the time that's too difficult so what about four 00:23:31 degrees C because actually the two degrees C we're heading towards is probably nearer three now anyway so I'm betting on your probabilities so let's think about four degrees C well what it gives you as a larger carbon budget and we all like that because it means I can 00:23:43 attend more fancy international conferences and we can come on going on rock climbing colleges in my case you know we can all count on doing than living the lives that we like so we quite like a larger carbon budget low rates of mitigation but what are the 00:23:54 impacts this is not my area so I'm taking some work here from the Hadley Centre in the UK who did some some analysis with the phone and Commonwealth Office but you're all probably familiar with these sorts of things and there's a range of these impacts that are out there a four degree C global average 00:24:07 means you're going to much larger averages on land because mostly over most of the planet is covered in oceans and they take longer to warm up but think during the heat waves what that might play out to mean so during times 00:24:18 when we're already under stress in our societies think of the European heat wave I don't know whether it got to Iceland or not and in 2003 well it was it was quite warm in the West Europe too warm it's probably much nicer 00:24:31 in Iceland and there were twenty to thirty thousand people died across Europe during that period now add eight degrees on top of that heat wave and it could be a longer heat wave and you start to think that our infrastructure start to break down the 00:24:45 cables that were used to bring power to our homes to our fridges to our water pumps those cables are underground and they're cooled by soil moisture as the soil moisture evaporates during a prolonged heatwave those cables cannot 00:24:56 carry as much power to our fridges and our water pumps so our fridges and water pumps can no longer work some of them will be now starting to break down so the food and our fridges will be perishing at the same time that our neighbors food is perishing so you live 00:25:08 in London eight million people three days of food in the whole city and it's got a heat wave and the food is anybody perishing in the fridges so you think you know bring the food from the ports but the similar problems might be happening in Europe and anyway the tarmac for the roads that we have in the 00:25:19 UK can't deal with those temperatures so it's melting so you can't bring the food up from the ports and the train lines that we put in place aren't designed for those temperatures and they're buckling so you can't bring the trains up so you've got 8 million people in London 00:25:31 you know in an advanced nation that is start to struggle with those sorts of temperature changes so even in industrialized countries you can imagine is playing out quite negatively a whole sequence of events not looking particulate 'iv in China look at the 00:25:44 building's they're putting up there and some of this Shanghai and Beijing and so forth they've got no thermal mass these buildings are not going to be good with high temperatures and the absolutely big increases there and in some parts of the states could be as high as 10 or 12 00:25:56 degrees temperature rises these are all a product of a 4 degree C average temperature

The indicative potential of demand-side strategies across all sectors to reduce emissions is 40-70%15by 2050 (high confidence)