UN Climate report: Dissecting the key messages, from the dire to the less direct

The United Nations Intergovernmental Panel Climate Change (IPCC) released its latest landmark report on global warming and its impacts today.

Many of the mainstream press accounts convey a dire message:  Unchecked, the IPCC finds global warming may lead to global food shortages, increase violence, exacerbate poverty, displace millions of people, and threaten human health.

On the other hand, some of the more nuanced analyses of the voluminous assessment strike a less pessimistic tone. They say the report emphasizes climate change is just one of many drivers of future environmental woes, that there are significant uncertainties in the future pace of climate change and that the effects will be spread out unevenly. And furthermore, they note the report finds some adaptation measures show promise for coping with global warming’s worst effects – though they may prove insufficient for rapid rates of change.

A take-home theme of this latest IPCC report and past editions – conveyed across the the board –  is that climate change risks increase dramatically the more it warms, and that reducing greenhouse gas emissions lowers the risk of the most unwelcome consequences (and need for adaptation).

Infographic showing the risk of climate change for different degrees of warming (IPCC)

Infographic showing the risk of climate change for different degrees of warming (IPCC)

This set of press accounts paints an unmistakable picture of the dangers posed by uncontrolled climate change, based on their reading of the IPCC:

The effects of man-made climate change, from sea-level rise to increasingly acidic ocean waters, have already become starkly apparent throughout the world. These effects are poised to worsen dramatically in coming decades due to continued emissions of greenhouse gases from the burning of fossil fuels and deforestation, according to a major new scientific report released on Sunday. - Andrew Freedman, Mashable

If the world doesn’t cut pollution of heat-trapping gases, the already noticeable harms of global warming could spiral “out of control,” the head of a United Nations scientific panel warned Monday. - Seth Borenstein, the Associated Press

Climate change is already having sweeping effects on every continent and throughout the world’s oceans, scientists reported on Monday, and they warned that the problem was likely to grow substantially worse unless greenhouse emissions are brought under control. - Justin Gillis, the New York Times

In a new U.N. report released on Monday morning (Japan time) scientists come to a stark conclusion: Unless the world changes course immediately and dramatically, the fundamental systems that support human civilization are at risk. - Eric Holthaus, Slate

On the other hand, consider these more nuanced perspectives of the IPCC’s message:

Behind such headline scares, though, lies a subtler story, in which the effects of global warming vary a lot, in which climate change is one risk among many, and in which the damage—and the possibility of reducing it—depends as much on the other factors, such as health systems or rural development, as it does on global warming itself. -J.P., The Economist

….careful readers will note a new tone to its [the IPCC's] discussion of these issues that is markedly different from past efforts. It is more humble about what scientists can predict in advance, and far more interested in how societies can make themselves resilient. It also places climate risks much more firmly than before among a host of other problems faced by society, especially by the poor. That tone will annoy some for taking the edge off past warnings, but gratify others for providing a healthy dose of realism. – Fred Pearce, Yale Climate Media Forum

These latter accounts note IPCC often frames climate change as part of an interconnected web of environmental and social challenges rather than the sole cause.

“The new assessment for the first time looks at climate change not just as a problem in its own right but as something that is merely part of an even bigger context,” concludes the Economist piece.

As an example, on the issue of increased violence and conflict due to climate change, an excerpt from a report in Al-Jazeera characterizes climate change as a “threat multiplier” rather than the driver of civil conflict:

“Climate change will not directly cause conflict – but it will exacerbate issues of poor governance, resource inequality and social unrest,” retired US Navy Admiral David Titley, now a Pennsylvania State University professor of meteorology, wrote in an email. “The Arab Spring and Syria are two recent examples.”

But Titley, who was not part of the IPCC report, says “if you are already living in a place affected by violent conflict I suspect climate change becomes the least of your worries”.

In a another example of climate change acting as a long-term stressor (rather than root cause), the NY Times’ Andrew Revkin notes climate change-induced sea level rise is a small add-on to the immediate inundation risk in the Bangladesh Delta caused by dam construction and groundwater pumping.

What’s particularly notable and disturbing about the situation in crowded delta regions like Bangladesh is that the rise in sea levels is, for the moment at least, not even close to the main driver of inundation risk.

The damming of Asia’s great rivers has greatly reduced the sediment flows that created the deltas in the first place and maintain them now.

Irrespective of whether climate change is the primary cause of future challenges or a contributing factor, the report stresses the need for adaptation initiatives to confront its risks to agriculture, water resources, and human health among other areas.

From Steve Mufson’s piece in the Washington Post:

Michael Oppenheimer, a professor of geosciences and international affairs at Princeton University and one of the report’s authors, said: “There is a more optimistic tone about our ability to adapt to some of these things. We’ve had some bad heat waves and coastal storms, and we have a better idea of what we need to do. Whether we will ever do it, I don’t know.”

But he cautioned that “everyone agrees that if we don’t slow the warming down, our prospects for adaptation are not good.”

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