Climate Change: $, Food, our lives, our homes, …

This has been an eventful week on the issue of climate change.  The Copenhagen Climate Change conference has resulted in a flurry of publications and discussions.  All of which should compel us to stop. Stop. Think. Re-examine.

Let’s start with looking at (some of) the world’s largest polluters.

*If climate change is “severe,” then “half the world’s inhabited areas [could become] literally too hot to live in, a US scientist warned today.”

Steven Sherwood, a climate expert at Yale University, told a global warming conference in Copenhagen that people will not be able to adapt to a much warmer climate as well as previously thought.

The physiological limits of the human body will begin to render places impossible to support human life if the average global temperature rises by 7C on pre-industrial levels, he said.

“There will be some places on Earth where it would simply be impossible to lose heat,” Sherwood said. “This is quite imaginable if we continue burning fossil fuels. I don’t see any reason why we wouldn’t end up there.”

The 2007 report from the Intergovernmental Panel on Climate Change (IPCC) said that average temperatures could rise by 6C this century if greenhouse gas emissions continue to rise at current rates. Scientists at the Copenhagen Climate Congress this week said the IPCC may have underestimated the scale of the problem, and that emissions since 2000 have risen much faster than expected.

And if it is not so severe? “A 1ºC rise in temperature looks like a 25% increase in prices, hurting some poor farmers and a lot of poor consumers.” From the climate change feedback blog:

A sobering presentation by Marshall Burke of Stanford on future agriculture. He and colleagues looked at historical climate and yield data for various crops in various parts of the world and projected the relationship they found into various future climates as found in the IPCC. As the IPCC itself reported, much of the tropics did badly in this analysis, and the worst performer was maize in southern Africa which was down in yield by about 30% by 2030.

More granular data run out to 2050 showed similar or worse trends, and the rest of Africa did pretty badly too. So did other crops in the same countries, such as millet and sorghum, though as Andy Jarvis of Biodiversity International pointed out from the floor, this may be somewhat worst case. You don’t just go on growing the same thing as the situation gets worse and worse. As climates change so will the crops farmers grow, which should help a bit.

While the IPCC has already predicted that tropical agriculture will have its productivity hit by any climate change, it said it expected that in temperate zones modest warming might help productivity. In at least one case Burke went into — maize in the US — there are studies suggesting things start going wrong much sooner than that, with yield losses of 30% or so by 2030. Modest rises have been seen: sharp downturns are to come. Burke says that an economic model fed with these and other gloomier-than-common yield assumptions suggests that prices are set to rise more steeply than the IPCC has foreseen: a 1ºC rise in temperature looks like a 25% increase in prices, hurting some poor farmers and a lot of poor consumers.

As Burke pointed out, we care about these food security issues because we care about people. A World Bank study suggests that the food crisis of 2007-2008 pushed 100m people into poverty. Reduced yields are normally bad for poor farmers, for whom consequent price increases rarely make up for lost production. They are also bad for the urban poor, who just see the price increases. That 25% increase in prices will some poor farmers and a lot of poor consumers. And on current trends that’s just the beginning.

Scientists at the Copenhagen meeting issued a strong statement. (Their full findings will be published in June)

“The climate system is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived. These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events. There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts.”

The summary adds: “There is no excuse for inaction. We already have many tools and approaches – economic, technological, behavioural, management – to deal effectively with the climate change challenge. But they must be vigorously and widely implemented.”

Given those reports (and so much more), it is thus not surprising that Lord Stern, who issued the now-famous economic report arguing that the economic cost of inaction is significantly more than the economic cost of transforming our economy. Now, he says he underestimated the costs!

“Speaking after giving a keynote speech, Stern said he feared that politicians had not grasped the seriousness of the crisis. “Do the politicians understand just how difficult it could be? Just how devastating four, five, six degrees centigrade would be? I think not yet. Looking back, the Stern review underestimated the risks and underestimated the damage from inaction.”

So what has changed since the Stern report was published in 2006?

Then and now: How Stern’s view changed

Temperatures

A central assumption of the 2006 Stern Report was global temperatures would rise by between C and 3C over the current century if nothing was done to counter global warming.

Stern also mentioned the possibility of a 4C rise.

Yesterday, Stern said 4C, 5C, 6C and even 7C degree rises were a real possibility by the end of the 21st century, taking the world into new territory – agriculture would be destroyed and life impossible in many areas.

Costs

Stern created a sliding scale in the 2006 report which measured the costs of doing nothing on climate change. At the upper limit was the chance the damage would amount to 20 per cent of global Gross Domestic Product – a fifth of the world’s wealth.

Yesterday, Stern revised his estimate saying the cost would be 50 per cent higher “or more” than the previous highest guess – risking a third of the world’s wealth or a 30 per cent plus reduction in consumption per head.

So, what to do? This is what the 2,500 scientists from 80 countries say from their summary statement to policy makers:

To achieve the societal transformation required to meet the climate change challenge, we must overcome a number of significant constraints and seize critical opportunities. These include reducing inertia in social and economic systems; building on a growing public desire for governments to act on climate change; removing implicit and explicit subsidies; reducing the influence of vested interests that increase emissions and reduce resilience; enabling the shifts from ineffective governance and weak institutions to innovative leadership in government, the private sector and civil society; and engaging society in the transition to norms and practices that foster sustainability.