I spent the last couple of days reading a presentation on climate given in September by the Apollo-Gaia project, an organization formed of scientists and thinkers that advises the Club of Rome, amongst other institutions. You can find it HEAR.

 

The presentation was made to explain some recent developments in climate science that revise the earlier models used by the bodies who advise the international climate negotiations. This includes the IPCC, which is the authority most governments have been following over the years, and who released their 5th report in 2013. You probably won’t be surprised to hear that the situation is more serious than these institutions have told us. In short, the forecasts are too conservative, because the old models have excluded feedbacks that accelerate global warming as the planet heats up.

 

In fact, according to this new analysis, CO2 in the atmosphere only accounts for a fraction of the increase in global temperatures predicted by the models. The rest comes from feedbacks that are triggered by the temperature- whatever is causing that temperature change, which in the case of manmade climate change are greenhouse gases.

 

In brief, the sensitivity of the Earth’s climate system is higher than previously thought. The science behind this is complex and I would recommend reading the whole paper to get the full explanation. However, a summary of the main implications:

 

Feedbacks in the Earth Climate System are activated by temperature. Some of these respond quickly (fast feedbacks), activated over a few years perhaps- like losses in the cloud covering the Earth.

Others take longer to get underway- such as melting of the great ice sheets and glaciers that reflect solar radiation from the Sun back into space.

 

The important metric for quantifying climate change is the eventual temperature that will be reached due to the state of the feedbacks, not just the CO2 (and other greenhouse gases) concentration. The higher the temperature, the more feedbacks are activated.

 

Because of slow feedbacks, the temperature we will eventually reach (nobody can predict exactly when) if CO2 keeps it’s current level of 400ppm, or the level of 450ppm targeted by climate negotiations, is too high- it would have catastrophic outcomes, enough to initiate runaway climate change of 4+ degrees.

There is no carbon budget left to avoid catastrophic climate change- humanity now has a carbon debt. It is not enough to stabilize atmospheric CO2- the concentration must be reduced to well below 350ppm (as low as possible).

 

Some good news: The feedbacks that we will likely trigger on our emissions trajectory do not activate immediately. It takes a number of decades- up to around 60 years, maybe- to reach the point where the Earth is moving fully into a new climate state, characterized by a much higher temperature. At that point, there is not much humanity can do as the climate system has the momentum of the entire planet driving it. The 60 years is an estimation, of course, but you can be fairly sure of the energy needed to make those kind of changes to the Earth- and it corresponds to a lot of sustained warming, so the prediction is unlikely to be far off.

 

Accordingly, humanity should be preparing not only a zero carbon economy, but a carbon negative economy where we are drawing carbon down from the atmosphere in order to meet our food and energy needs. That is a daunting task, but the means to do it exist. Some features of the carbon negative economy might be:

  • Reforestation. We should direct research into producing trees that can withstand climate extremes that we have already committed ourselves to. Tree planting and stewardship could be a major source of employment over this century.
  • Biochar is a form of charcoal produced from burning organic matter without oxygen (in sealed containers). It locks up the carbon that would be released from decaying vegetation, preventing it’s release into the atmosphere (not decaying for thousands of years). It has the added benefit of increasing soil fertility. Scaled up, there is the potential for carbon-negative biomass power stations.
  • Anaerobic digesters take some types of rotting vegetation and food waste and turn it into methane, or biogas. This gives a carbon neutral or carbon negative source of fuel for transport and heating.

This is on top of the renewables that are needed to replace fossil fuels.

 

In the short term, the conclusion is the same as before; humanity’s immediate priority is to decarbonize our energy, transport and agricultural systems. But we should be preparing for the next stage.

In addition, we need to find other ways to cool the planet should the carbon negative economy not prove enough to mitigate global warming to the degree necessary. Depending on the definition you use, this may include the controversial notion of ‘geoengineering’. But there are many other, more benign things that we can do, such as increasing the whiteness of the Earth to make up for lost ice, whitening clouds, and others. I’m going to post soon on this topic.

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Hi,
No i don't have an answer. My sense is that people change through 'owning' their own sense of hope and self empowerment, rather than 'what the heck, we're all going to die so lets get creative'.  It feels like we are being liberated by our fear of the future, and psychologically not sure that is human nature. Fear feeds denial and blocks change?
Ultimately one of the mantra's of the eco movement, which i subscribe to, is think global act local... very much Transition's ethos. However for many in the wider 'struggle for a better world' its other issues than climate change that compels them to get involved, so we need to connect with where people is at... anyway I am not offering a solution ... maybe other voices can help us (me) out.
All the best, Jez

In addition, we need to find other ways to cool the planet should the carbon negative economy not prove enough to mitigate global warming to the degree necessary. Depending on the definition you use, this may include the controversial notion of ‘geoengineering’. But there are many other, more benign things that we can do, such as increasing the whiteness of the Earth to make up for lost ice, whitening clouds, and others. I’m going to post soon on this topic.

   All very sensible and, I have no doubt, very necessary. However, the calm and rational language used in these reports (and in this summary) is utterly divorced from the total absence of any effective action towards achieving any of these goals. There are no plans by any of the major players to move to a carbon neutral economy, let alone a carbon negative one. There are targets in place for some economies to reduce the level of emissions but not even the most technologically advanced economies (Western Europe, Japan and North America) envisage achieving carbon neutrality in the foreseeable future and there is no political will by our current leaders to confront the difficulties that stand in the way of such plans. At present the indications are that the global economy will not even manage to meet its existing, wholly inadequate, targets to hold emissions steady or reduce the rise in CO2 in the atmosphere.

   While scientists use this dispassionate, calm and rational language to report the observable effects and to chart the most likely timescales for these enormous and planet altering changes to take place, the forces driving our economies and our governments continue to ignore them and take no effective action. Further, the science cannot predict what will happen but merely sets out possibilities. Many scientists do not accept that we can live with an average rise of 2 degrees (cent) - which is the current target (based on proposed cuts in CO2 emissions which are not going to be realised on current trends anyway). Many scientists do not accept that it is even possible to hold a temperature rise of 2 degrees even if we do halt (not reduce... halt) carbon emissions as a 2 degree temperature rise might well set off unstoppable feedback processes, such as the massive release of methyl hydrates, which could rapidly send the temperature much higher.

   Our current economic and political system is incapable of taking the action necessary to confront these dangers because it is based on the absolute necessity to achieve and maintain 'economic growth' at the expense of everything else - even the future existence of human civilisation (and if that sounds completely insane then you're right... it is). Until we translate concern over climate change into effective political action to change our economic system then we are simply walking (or perhaps running) towards a precipice with no idea how far we might fall and what kind of surface we might fall onto.

There's a pertinent blog by George Monbiot in today's Guardian, which I thought is worth reading - about why it's so hard to get anything done these days, even though we know better

http://www.theguardian.com/environment/georgemonbiot/2014/sep/11/st...

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