Chris Field discusses runaway climate change

Chris Field of the Carnegie Institute, Washington, discusses the nitty gritty of climate change with Matthew Wright and Scott Bilby of Beyond Zero Emissions.
There are huge quantities of super-potent methane in the Siberian Permafrost.  How much will escape into the atmosphere is uncertain.  Perhaps enough to initiate runaway climate change.

Chris Field discusses runaway climate change

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Transcript

Scott Bilby:  Good morning. Welcome to Beyond Zero, a program that covers issues relating to climate change, including the latest news, science solutions and community actions. This show is produced by Beyond Zero Emissions, an Australian-based climate change campaign centre. We differ from mainstream environmental groups on one very important point: our understanding that human caused global warming has already exceeded safe limits and that we must act immediately to reduce our levels of greenhouse gas emissions to zero and below.

You’re tuned to 3CR and the time is 8:37. My name is Scott Bilby, and with me in the studio is fellow presenter Matthew Wright and paneling for us this morning is Ian Sheehey. Good morning Ian and good morning Matt.

Matthew Wright:     Good morning.

Ian Sheehey:           Good morning.

Scott Bilby:  This morning on Beyond Zero we’re talking with Dr Chris Field. He’s the director of the Department of Global Ecology at Carnegie Institution of Washington at Stanford University. He’s the author of more than 200 scientific publications and his research emphasises the impacts of climate change, including local and global scale climate change patterns, vegetation climate feedbacks, carbon cycle dynamics, primary production, forest management and fire. Dr Field was a co-ordinating lead author of the fourth assessment report by the Intergovernmental Panel on Climate Change. He’s also a fellow of the Aldo Leopold Leadership Program and he’s also a member of the US National Academy of Sciences. Dr Field joins us live from the United States. Hello Chris, thank you for joining us.

Chris Field:  Thank you. It’s a pleasure to join you.

Scott Bilby:  It’s a pleasure to have you speaking with us this morning. Now Chris, we’ve spoken to many people who’ve made global warming a focus in their lives and we’ve heard about the different paths they have traveled to get where they are now. So can we just start off by having you tell us how global warming became a focus in your life?

Chris Field:  Well, I have always been interested in the environment. My formal training is in biology. I started life as a scientist trying to understand how plants adapted to different kinds of environmental conditions, and as I learned more and more about the way plants worked it was obvious that they were sitting in ecological and environmental contexts that were changing, and in many cases changing very rapidly. And about 20 years ago I realised the scientific uncertainties with climate change provided an incredibly frightening but also an incredibly rich scientific area.

There’s just a wonderful overlap between things we would like to know about the way the world works and things we need to know in order to ensure that we can provide a sustainable future.

Scott Bilby:  Now, I’d just like to ask you – I’ll talk to you about some of your priorities at the moment, but you recently told the American Association for the Advancement of Science at a meeting in Chicago in February this year was it? I think that the – and you said that the IPCC’s last report on climate change in 2007 had substantially underestimated the severity of global warming over the rest of the century. Can you tell us a little bit more about that, the talk at the American Association for the Advancement of Science and what you actually said there?

Chris Field:  Sure. The IPCC provides a substantive update on where the scientific community is at any given point in time, but the science continues to move. What we’ve seen is the release of the last IPCC report that’s really concerning to me involves three main areas.

The first is the forcing of climate change: how many greenhouse gases are being emitted. The second concerns feedback: the ways that land and ocean interact with the climate system to either amplify or suppress the warming. And the third is in the responses of the Earth system. And in each of those I think we’ve seen changes that were either at or greater than the most rapid or largest magnitude changes that the IPCC considered. In the area of forcings, we have seen human emissions of greenhouse gases increase by 3.5 per cent per year from 2000 to 2007. The rate of change from 1990 to 1999 was only 0.9 per cent per year, and the rate of increase since 2000 has been so rapid that in recent years the CO2 emissions have tracked either at or even above the full range of possibilities that were explored in detail by the models that the IPCC has set.

As a consequence, the CO2 emissions in recent years were about half a billion tonnes per year greater than the highest emissions scenario that was looked at by the IPCC. Essentially what that means is that we’re moving into a trajectory of climate change that has not been explored in detail with the climate model.

A second area of significant concern is that we’re seeing some increasing evidence of very powerful feedback that takes the direction of emissions cycles where warming increases the rate of release of CO2 from terrestrial eco-systems or decreases the rate at which land and ocean systems can take up CO2. And some of these were considered by the IPCC as kind of a sidebar issue. Some weren’t considered at all.

The two that look like they’re the biggest concerns is decreasing rates of CO2 uptake in tropical forests, and we’ve seen recent publications documenting profound effects of tropical drought in decreasing CO2 uptake. What we’ve also seen, a large number of climate model simulations that confirm the idea that warming in the land and oceans decreases carbon uptake in tropical forests, which increases the amount of CO2 that stays in the atmosphere, which increases global warming.

The second big area of concern in land eco-systems concerns high latitude eco-systems where the soils are frozen all the time in permafrost soils, and in many cases these soils contain large amounts of frozen organic matter that, when thawed, can decompose rapidly into carbon dioxide or into methane, an even more powerful greenhouse gas, and this process of thawing permafrost looks like it could proceed quite rapidly but has not been considered at all in the detailed analysis that the IPCC has considered.

The third area of concern is in the area of responses, and I think that there are two main responses that have occurred very clearly, much more rapidly than had been anticipated and are now occurring at rates that are right at the upper limits of those that have been considered by the IPCC, and that concerns the loss of Arctic sea ice which has in recent years been at levels that were as much as 35 per cent below the long term average, and the other is the rate of sea level rise where we’re seeing now that more than half of the recent sea level rise is coming from melting of ice on land and less than half is coming from thermal expansion of the water. The expectation – no, not really the expectation – the IPCC said it couldn’t deal with the problem of land ice melting in detail, and so they didn’t really include that in their estimates. But now it appears that it’s the dominant term.

Scott Bilby:  And so you mentioned there, terrestrial systems such as the permafrost and the tropical rainforests. Now, I read something where you said that the permafrost could potentially release up to 1000 or approximately 1000 billion tonnes of CO2 into the atmosphere which is currently trapped in – well it’s technically in its soils I guess – in that frozen sort of vegetation. If that was released, what sort of impact could that have?

Chris Field:  I think that the most useful way to think about this is to position the potential magnitude of these permafrosts releases against both the annual releases from fossil fuel and the cumulative releases from fossil fuel combustion since the beginning of the Industrial Revolution. In 2007 human combustion of fossil fuel released about 8.5 billion tonnes of carbon in CO2 to the atmosphere. Since the beginning of the Industrial Revolution, human activities have released about 350 billion tonnes of carbon into the atmosphere and about 40 per cent of that has stayed. We think now that these frozen soils and the permafrost contain somewhere between 1500 and 2000 billion tonnes of carbon frozen in them. We don’t have very accurate assessments yet of how much of that might be released in meltings over the next century, but it is certainly within the realm of the risk assessments that have been done to estimate that perhaps 100 to 200 billion tonnes of carbon might be released. That is one-third to two-thirds of the total amount that’s been released by human activity since the beginning of the Industrial Revolution. It’s enough to really change the fundamental equation of where the forcing of climate is coming from.

Scott Bilby:  Now we’re speaking with Dr Chris Field, director of the Department of Global Ecology at Carnegie Institution of Washington at Stanford University. Now Chris, we talk about the melting of the permafrost, for example, and other things – the loss of the tropical forests, all sorts, and, you know, in Australia we’ve got huge forests in southeast Australia too, but all manner of different things that could release carbon into the atmosphere. Essentially a lot of people kind of have the impression that, oh look, if we go up to two degrees Celsius above pre-industrial levels, you know, the world’s going to be this bad, and if we go to three degrees it’s going to be a little bit worse again, and four degrees, if we stop there, it’ll be a little bit worse again. Like, surely we’re going to reach a point where we don’t just - humans don’t decide at what temperature increase we’re going to stop. You know, at some point we’re going to trip a point where we won’t have any choice. It will just run away from, say, two or three degrees and go straight up to six degrees, and there’ll be nothing we can do. We’ll just sit back and watch it. Is that correct?

Chris Field:  Ah, unfortunately we don’t know the answer with a high level of confidence. These feedback mechanisms that I’ve been talking about that tend to operate in the vicious cycle direction have the potential to amplify whatever amount of global warming is caused by human release of greenhouse gases. That global warming could be further amplified by loss of high latitude snow and ice cover. Most of the simulations don’t indicate that we’re approaching a threshold, but that if we totally stopped emitting greenhouse gases the climate would continue to warm. But there are lots of lines of evidence that indicate that these vicious cycle feedbacks from the land and ocean systems are going to make it increasingly difficult to move away from the large levels of warming the closer we get. And I think that the way a rational person would deal with this lack of certainty on this is to say OK, even though we’re not 100 per cent certain that there’s a vicious cycle feedback that would lead without any possibility of exception to a warming of, you know, six, eight whatever, that the risk is great enough that we should be taking major efforts to avoid a possibility of it occurring.

Scott Bilby: OK. Now we’ve talked about some of the problems and I’d like to get on, with the time we’ve got left, to talk about a few solutions and in particular your work. And now, please feel free to talk about what you think is the most salient bit of work that comes to mind – that you think is most appropriate in this respect. But perhaps we could talk about biofuels? Because in Australia, and I guess around the world, the average person has this idea that biofuels well, you know, we hear they’re good and then sometimes we hear they’re bad and we’d probably like to hear your views on that, given your expertise in that area.

Chris Field:  Biofuels are an incredibly complicated set of issues. You can’t really talk about biofuels without talking about food security. And food security for people is in many ways kind of the eye of the perfect storm. Human populations continuing to increase; climate change is putting food security at risk in some areas. Increasing preference for meat in many countries is putting additional pressure on the food system, and then biofuels are also putting increasing pressure on the food system. But one of the things I think we need to make a priority when we think about biofuels is how do we extract biofuel or biomass energy from places that aren’t required for food production.

The second thing we need to be really careful about with biofuels is to make sure they’re not taken from areas or produced in a way that releases as many greenhouse gases into the atmosphere as are offset by not using the fossil fuels. And there are a number of mechanisms by which biofuels can be climate unfriendly. One example that’s relatively well understood is if one goes in and cuts down a large forest and that forest is either burned or decomposes and releases its carbon content into the atmosphere, it can take many decades or even centuries for the biomass energy that’s extracted in cropping in order to recover that carbon debt that was incurred by cutting the forests.

Another mechanism by which biofuels can be environmentally unfriendly or climate unfriendly is if the bioenergy crop is fertilised with large amounts of nitrogen fertiliser, such that some of the nitrogen is released to the atmosphere as nitrous oxide which is another very powerful greenhouse gas, about 300 times as powerful as carbon dioxide. And the effort to produce high yields of biomass energy, especially from traditional agricultural crops like corn, can result in significant releases of nitrous oxides.

A third important area in which biofuels can be climate unfriendly is that some of the conversion processes that are used that can get from, for example, corn grain to liquid biofuel - to ethanol - can result in the consumption of fossil energy that’s almost as large as the production of the biomass energy that finally makes it into fuel tanks. That doesn’t mean that biofuels are without exception bad, but what it means is that there are important downsides that need to be avoided when one’s designing a climate energy system.

A lot of the work in my group has gone into two areas concerning biofuels. One is trying to figure out where on Earth we could sustain meaningful levels of biomass energy input into the energy system without putting food security at risk and without putting forest resources at risk where one would incur the large carbon debt. We end up with a very large amount of area globally that would be potentially suitable for bioenergy production. The numbers are about 400 million hectares globally, with the countries with the most potential, the countries where there are relatively large amounts of abandoned crop land and pasture in terms of area. We think the United States, Brazil and Australia are the three countries with the most potential for the long-term protection, production of biomass energy.

Another aspect of biomass energy that I think is really worth seriously considering is that as we look at a range of futures that have many aspects that make them unacceptable in climate terms, we should be looking hard at strategies for not just decreasing the CO2 emissions of the atmosphere but actually moving to negative emissions. And one of the sets of technologies that could lead us to negative emissions, technologies that actually produce energy while removing carbon dioxide from the air would involve using biomass production which takes up carbon dioxide in photosynthesis, converting that biomass to energy, therein a combustion based power plant or another kind of power plant, and then takes the CO2 that’s released from that combustion and sequestering it in geological formations.

And I think that, from my perspective, biomass energy provides one of the only proven technologies that can scale and actually remove CO2 from the atmosphere. And I think for that reason it’s an attractive possibility to explore for strategies that might yield net negative emissions.

Matthew Wright:     Now, Dr Chris Field, you did mention carbon debt, and that was really interesting, and negative emissions. Do you have any policy suggestions around that? Do you think that sovereign countries, especially Western countries like the United States and Australia, who are historically responsible for putting the carbon emissions up in the atmosphere, should actually perhaps have that booked against their accounts, and they should actually pay for these negative emissions? Paying for removing carbon from the atmosphere. So if Australia put up eight billion tonnes historically they should have to pay to put eight billion tonnes down under the soils.

Chris Field:  That’s the whole issue - of how to distribute responsibility for historical emissions - is a really challenging one. And I think it’s clear that we shouldn’t base responsibility purely on current emissions, and I think it’s certainly clear that we shouldn’t base responsibility purely on future emissions because obviously the problem that we’re dealing with now is a cumulative problem that is a consequence of the complete historical trajectory. But I also think that we’re going to need to find a solution set that works that can get buy-ins by the full range of global players. And I think that that’s going to involve a wide range of technology and policy levers that may or may not include some kind of assignment of responsibility for historical emissions. That’s an area that I think you can separate what you would ideally like to see in terms of the mechanistic responsibility, and what might be possible in the detailed and intricate realm of international policy negotiations.

Matthew Wright:     Yeah. On those policy negotiations – there was just a recent conference in Copenhagen that was updating the IPCC science - and I don’t know if you were directly involved in that - but do you think that policy makers are now acutely aware of just how serious the observed climate change is now. You know because, say, Ken Caldeira and James Hansen and a few scientists have been out there saying things are really quite bad. But now, is it on the record now and we can take policy makers to account on this?

Chris Field:  You know, I think that if you look at the recent papers, they basically confirm that the IPCC reports provide a conservative estimate. All the world’s governments have bought in to the IPCC reports and accept the scientific conclusions that they draw, and recent meetings like the Copenhagen one, clearly emphasise new science that highlights in many cases the issues that make climate change more of a serious problem than it was before.

My sense is that around the world we’re seeing a lot more comprehensive and serious buy-ins by policy makers. That’s certainly the case in the United States. The Obama administration brings incredibly refreshing commitment to serious action on climate. But at least in the United States we’ve also seen how problematic that is, where even as there’s been movement in the Congress to consider some really quite ambitious climate targets, there has been scepticism from states that are heavily dependant on coal-based electricity. So I think that we still see an environment in which even the recognition of the problem hasn’t really been sufficient to generate the universal buy-in that’s going to be required for ambitious policy action.

Scott Bilby:  Now Chris, can we just – we’re running out of time – but can we just kind of get a statement on what you’re working on at the moment - just quickly.

Chris Field:  In terms of biomass energy, my group has been working on trying to figure out whether we can use biomass energy most efficiently by running it through the conversion of liquid fuels like ethanol or by running it through traditional power plant generation by co-firing with coal. And the answer looks like it’s going to be surprising, that in many settings that the most efficient way to use biomass energy is actually to use it for the production of electricity.

We’re also continuing to work on experimental studies where we expose eco-systems to simulated climate changes and try and understand the whole range of impacts, including things that are so subtle that they wouldn’t necessarily be included in any of the available models.

Scott Bilby:  OK. That’s fantastic to hear. And I am afraid we are going to have to leave now. But thank you very much Dr Field for joining us this morning on Beyond Zero.

Chris Field:  It’s been a pleasure to talk with you.

Matthew Wright:     We’ll hopefully speak to you again soon.

Scott Bilby:  Thank you very much. Now that was Dr Chris Field, director at the Department of Global Ecology, Carnegie Institution of Washington at Stanford University. He’s the author of more than 200 scientific papers and his research emphasises the impacts of climate change. If you want to know more about Chris, you can go to leopoldleadership.org and you can scroll down the A to Z list of the Fellows Directory and you’ll find him there.

So, before we go, I’ll just say you’ve been listening to Beyond Zero, and you can find out more about us on www.beyondzeroemissions.org.