The fossil fuels we can't touch

Climate change and global warming are strongly linked to rising carbon dioxide or CO2 levels in the atmosphere, which partly come from burning fossil fuels. The world's politicians have agreed that a 2-degree Celsius rise in global temperature is as much as the world can take. Recent research, published in Nature, has revealed that many of our untapped fossil fuels with have to stay firmly underground if we are to avoid this 2-degree rise.

Researchers Cristophe McGlade and Paul Ekins from University College London explained the work to Kat Arney, also discussing the tough choices the world will have to make if we want to avoid the worst-case-scenario...

Cristophe -   This model looks out into the very long term up to 2100 and says, how can we best meet all of our energy needs in the future in a global context. It finds the cheapest way of satisfying all of the energy uses we might have in the future - how we're going to heat our buildings in the future, what we're going to use to drive our cars, how are we going to produce all of the industrial goods? For this work, what we did was we imposed this 2 degrees constraint on the model. So, we said that carbon emissions resulting from use of oil, from gas and from coal cannot result in a temperature rise which is above the 2 degrees target.

Kat - And so, when you look at this, how much can we use of the stuff we know is there in the Earth?

Cristophe - Of the coal reserves, only about 20% of these can be used. So, that means that 80% of current coal reserves have to stay in the ground if we don't want to exceed 2 degrees. For oil, it's about a third needs to stay in the ground and for gas, it's about half of what we think is currently economic to extract has to be left in the ground.

Kat - This seems pretty significant because obviously, there must be energy companies who have made predictions, who were going out looking for more oil and stuff in the ground. We talk about fracking, we talk about exploiting the oil that's under the Arctic. It's a bit difficult to say to them, "You know what guys, you can't even take the stuff that you think you've got."

Cristophe - Absolutely and there's a big inconsistency currently between what trajectory the world is currently on and what people have agreed to. So yes, the fossil fuel companies which are continuing to explore for new resources need to be aware that this is completely inconsistent with the 2 degrees target.

Kat - Oil and gas, and coal reserves that we have aren't equally distributed between all countries. So, how do some of the things shape up in terms of which countries have to be on the strictest carbon diet?

Cristophe - Generally, those regions which have the most resources currently are going to have to go on the biggest carbon diet, as you call it. For coal, the United States and Russia can only use less than 10% of their current reserves. In the Middle East alone, there's about 260 billion barrels of oil. That's the entire oil reserves of Saudi Arabia which needs to remain in the ground if we don't want to exceed this 2 degrees.

Kat - One of the things that comes out of your paper is that we can't even burn the resources that we know that we have and yet, companies are exploring in places like under the Arctic, we're looking at technologies like fracking which is very contentious at the moment. You're calculations would suggest that this is basically a waste of time.

Cristophe - Yes. So, within the model, we identify all of these different resources that are out there and you mentioned the Arctic. We can look at, under this 2 degrees scenario, which of these resources are actually used and the results suggest that actually, the Arctic oil and gas, and there might be quite a lot of oil and gas out there isn't required if we want to stay within 2 degrees. Some of the other sources you mentioned, you mentioned shale gas from fracking, there is some potential for that to be used particularly if we have a rapid reduction in coal consumption in the future, some gas will have to come through. And some of that gas can be shale gas. However, if countries such as the UK decide to develop its own shale gas resources, it has to be aware that as a result, someone else somewhere else isn't going to be able to use all of their reserves. So, there's always this trade-off between, if we exploit here, someone else has to not exploit somewhere else.

Paul - It's an enormous challenge because countries quite legitimately regard these resources as theirs and the decision whether they use them or not is their decision. They will need to agree not to use some resources somewhere. The countries that agree not to use their resources, they will probably wish to be compensated in some way. Those kinds of arrangements need to be on the table in the climate change negotiations.

Kat - Climate change is a global problem. It needs all the leaders of all the countries in the world to work together. Some countries say, "Well, no. we want to carry on. We want to develop. We want to use our resources." Is there hope realistically that countries can actually work together and come to these solutions. What's your personal feeling on this?

Paul - Yes, I'm very hopeful because I think increasingly, it will become obvious that climate change is something which they very much need to avoid. It may be true that money makes the world go round, but money doesn't go very far if you haven't got a liveable climate.

Kat - The projections in this paper go up to 2100. If you could maybe paint me a picture, perhaps over the next 20, 30, 40 years, how you would like see things changing?

Paul - Yes, things do change quite dramatically in the world in which we live over a period of two decades. So, I mean anyone who's more than about 40, if they look back 20 years, many of the things they now take for granted were not even dreamt of. It is my firm conviction that if we were to bite the bullet of low emission, energy systems and agriculture, by the time we got there and looked back, we wound wonder why we had thought it was going to be so painful. Because many of these technologies already exist, we can invest in them. A lot of them are not much more expensive than the technologies they're going to be replacing. So, my dream scenario is that both in the UK and globally, governments recognise the urgency of this issue and they start to do things like pricing carbon which will send investment in a quite different direction so that these low-carbon technologies become much more widely installed, emissions start to fall and publics become much more confident about the kind of trajectory that is possible.