Confronting Climate Change: A Scientifc Expert Panel Report

The New York Academy of Sciences hosted the launch of a UN Foundation sponsored report entitled "Confronting Climate Change: Avoiding the Unmanageable, Managing the Unavoidable".

The panel presentation is here, Q&A here and report here.

The key finding are:

	Climate change is reality and some of its results are now inevitable, but a new report offers a road map for mitigating and adapting to its effects.
	Allowing the global average surface temperature to rise more than 2°C to 2.5°C over the next 100 years would sharply increase the risk of catastrophic events. Greenhouse gases now in the atmosphere have already committed the planet to a rise of about 1.5°C.
	Climate change will lead to major crop failures, more extreme weather events, and make environmental refugees of tens of millions.
	Responding to climate change requires intelligent policy making and sustained investment in appropriate technology, both of which could help avert disasters resulting from climate change while simultaneously boosting living standards worldwide.

The really dismal science.
Peter Raven on the connection between climate change and sustainability.

Climate change may be the most media-unfriendly topic scientists have ever studied. It focuses on phenomena that are so gradual and insidious that they are virtually impossible to film; its conclusions reveal the terribly disturbing truth that the comfortable standard of living to which most of the world aspires is, in fact, destroying the planet; and its celebrity spokesman is Al Gore.

How, then, does one explain the current moment?

"Who would have thought that a singer singing a song about global climate change in a movie called An Inconvenient Truth would win an Academy Award for the best song in any movie in the United States in the past year? This gives you an idea of the situation that we've gotten to," says Peter Raven, director of the Missouri Botanical Garden...

...The meeting at the Academy was the first opportunity for the scientific community to learn about and respond to the report, and followed a meeting between the report's lead authors and UN Secretary General Ban Ki-Moon earlier that day...

Keeping our cool.
John Holdren on necessary steps for mitigating the effects of climate change.

The new report, written by an international panel of 18 scientists at the behest of the United Nations Commission on Sustainable Development, complements the series of reports now being published by the UN's Intergovernmental Panel on Climate Change (IPCC). "It differs from the IPCC report in that we have selected between possible reactions to climate change and provided a road map," says Raven, the Sigma Xi report's lead author.

Besides being more prescriptive, the Sigma Xi report is also more blunt than most politically vetted climate change assessments. The authors used similarly direct language in their presentations at the Academy. "Global climate change is real, it is primarily caused by human activities ... [and] it is accelerating," says John Holdren, director of the Woods Hole Research Institute.

Indeed, the evidence for human-driven climate change has become overwhelming in recent years. "The incidence of extreme weather events ... has been going up, sea level rise has been accelerating, sea ice is melting, glaciers are retreating, permafrost is thawing, boundaries of ecosystems are moving," says Holdren.

Researchers have linked the accelerating changes with the gigatons of carbon dioxide, methane, and other "greenhouse" gases emitted by human activities every year. By causing the atmosphere to retain more of the sun's heat, these emissions are driving the global average surface temperature inexorably upward.

Worse, the accumulating evidence suggests that climate change may not remain gradual. Several major "tipping points," such as the collapse of the West Antarctic ice sheet, major melting of the Greenland ice cap, desertification of the Amazon rainforest, and changes in the frequency of strong El Niño oscillations could cause sudden and catastrophic changes over the course of a few years rather than a few centuries. Climate change may be hard to sell, but it's become even harder to ignore.

The Sigma Xi panel concluded that allowing the global average surface temperature to rise more than 2°C to 2.5°C over the next 100 years would sharply increase the risk of these catastrophic impacts. Greenhouse gases now in the atmosphere have already committed the planet to a rise of about 1.5°C.

To stay within the recommended range, the researchers assert that human greenhouse gas emissions must stabilize not much above current levels no later than 2015, then decline to no more than one third of current emissions by 2100. Compounding the problem, these reductions must occur right when the world's poorest countries are making the transition to modernity—in other words, at the very moment when global energy demand is about to skyrocket.

Conceding that cutting emissions while raising living standards will be an immense job, Holdren is nonetheless optimistic: "It is a challenge to which we believe society can rise," he says. In order to meet it, the panel outlined a series of recommendations, highlighting the "win-win" solutions that cut energy demand while boosting economic growth.

Unfortunately, win-win solutions, such as increasing vehicle fuel economy and providing incentives for cleaning up power plants, will not be enough. The report admits that achieving long-term emissions reductions will also require "win-lose" solutions, such as a carbon tax or a "cap-and-trade" system of emissions permits.

Besides choosing the right solutions, policymakers will need to implement them properly. Picking one topical example, Holdren explains that "in the transport sector, we should be increasing the use of biofuels to replace oil, [but] we cannot do that witlessly, because expanding biofuels witlessly will pose serious problems of competition with food production ... environmental destruction, [and] loss of biodiversity."

Jousting the four horsemen.
Rosina Bierbaum on ways to adapt to inevitable climate change.

Food production and biodiversity were also major topics for Rosina Bierbaum, dean of environmental and natural resource policy and management at the University of Michigan, who spoke after Holdren. Using a pair of world maps, Bierbaum showed the group's projections of future ecosystem upheavals and crop failures.

Even if governments follow the panel's recommendations to mitigate climate change, some of these events are probably inevitable. "Adaptation to climate change can't any longer be seen as sort of a cop-out; it's not instead of mitigation, but it's needed in addition to mitigation," says Bierbaum.

In a generation, Mississippi may be growing coconut palms instead of loblolly pine lumber, and Vermonters' maple syrup might come from northern Canada. More ominously, major crop failures in the tropics could cause widespread famines in Africa, South America, and Southeast Asia. Meanwhile, rising ocean temperatures and sea levels will likely increase extreme weather events and displace entire communities from coastlines. "There will be tens of millions of environmental refugees that the world will need to deal with," says Bierbaum.

Michael MacCracken on how climate change is affecting the biosphere.

The most vulnerable countries are those in which agriculture accounts for more than 5% of GDP, and at least one important crop will be jeopardized by climate change. Among these countries are many that are already poor and underdeveloped.

But like the mitigation measures, many of the report's adaptation recommendations are easier said than done. During the question session after the presentations, for example, an audience member asked about the depressingly instructive case of New Orleans, where a multi-billion-dollar rebuilding effort is now underway on land that is infamously below sea level.

Raven concedes that the outlook is grim. "It's a lot easier to explain the problem than to forge a solution," he says, adding that "if we can't really address the problem of New Orleans in an intelligent and adaptive way, and the signs are relatively few that we will, how do we get together and address the problem of Bangladesh?"

The challenge goes well beyond building codes. "The wetlands that are south of New Orleans have been the shock absorber for hurricanes for a very long time, and they've been losing for the last 50 years about 25 square miles per year," says Michael MacCracken of the Climate Institute. MacCracken adds that "no matter what they do to New Orleans, if they don't recover the wetlands, they're going to get inundated [again]." The same is true for many other low-lying regions around the world.

Richard Moss on the international response to sustainable development.

Framing the issue more optimistically, Richard Moss, senior director of climate and energy at the UN Foundation, says that humanity still has the opportunity to choose between two futures. "The path that we're currently on ... involves increasingly serious climate change impacts," he says. In the alternative future, however, intelligent policy making and sustained investment in appropriate technology could help avert the climate change disaster while simultaneously boosting living standards worldwide. "We must act collectively and urgently to change our course through the leadership at all levels of society. There really is no more time for delay," says Moss.

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