UN climate panel only reports ‘facts’, but is it time to make clearer the implications for policy?
Do governments around Lake Chad need clearer advice on how they can conserve water from the IPCC? (Pic: NASA)
By Gerard Wynn
Governments may need firmer and clearer messages about climate risks, given the complexity of the science, where the Intergovernmental Panel on Climate Change could make its facts more policy relevant.
The IPCC, published on Monday, is the second in a three-part series documenting the threat of climate change, this time focusing on impacts.
It found that climate change was already happening and would become more dangerous if greenhouse gas emissions continued on a higher path.
On a brighter note, it found that ambitious investment in emissions cuts and preparations such as coastal defences and crop breeding would have a wider benefit, in reducing deadly air pollution, aiding disaster prevention and helping feed a growing population.
The IPCC only reports facts, leaving it to advocates and governments to interpret these.
“The role of the IPCC is not to motivate action,” said Stanford University’s Chris Field, a lead author of Monday’s report.
“Lots of organisations that are doing climate communications are like bells, they’re trying to ring as loud and as clear as possible. The IPCC is more like a bell tower intended to allow people to climb up to a height where they can get a clear view of what the present looks like and what possible alternative futures look like,” he told the BBC on Monday.
The danger of this approach is that it depends on “communication organisations” being informed and unbiased, where nuance and detail can lead to deliberate or accidental confusion.
In Britain, the BBC and UK Government were failing in their public duty to communicate climate science ‘clearly and effectively’, a panel of MPs said in a report published on Wednesday.
The Science and Technology Committee said the government’s “hands-off approach” to explaining why climate change is a threat had allowed “inaccurate arguments to flourish” unchallenged.
Complicated
Nuances and complexity may be ignored or lost, given the complexity behind the headline facts in IPCC reports.
One difficulty is detail.
Regarding crop production, for example, higher levels of atmospheric carbon dioxide from manmade emissions have a positive impact on crop yields.
While a higher level of CO2 can stimulate crop yields, however, it also reduces protein and mineral levels while maintaining calories, making food and fodder less nutritious overall.
Whether consumers benefit from these higher yields therefore depends on whether they most lack protein, minerals or calories.
The issue is unmentioned in the IPCC’s 44-page summary report, leaving it to the reader to dig into one of 30 background chapters, on agriculture, each more than 50 pages long, allowing commentators to claim unchallenged that higher carbon dioxide emissions can counter the damaging impact of climate change including droughts and heat waves on crop yields.
Another problem is uncertainty. Impact ranges can be exploited by lobbyists to exaggerate or diminish an outcome, by choosing one or other end of the range.
A third nuance is taking into account long term change.
The IPCC report focuses on climate changes this century, reflecting the bulk of the scientific research which it reviews.
The focus on this century fails to take account of a lag in the physical climate system, where the world will continue to warm and ice sheets melt even if emissions stopped tomorrow, a threat over many centuries which the IPCC allows a single sentence in its summary.
Mandate
Field’s view of the IPCC’s role as a bell tower, rather than bell, appears more restrictive than the IPCC’s actual mandate.
The IPCC is an intergovernmental body currently with 195 countries as members, and was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988 to provide the world with a clear scientific view.
“By endorsing the IPCC reports, governments acknowledge the authority of their scientific content,” the IPCC says of its mandate.
“The work of the organization is therefore policy-relevant and yet policy-neutral, never policy-prescriptive.”
Spelled out more clearly, the context of the IPCC’s facts need not be prescriptive, and indeed is essential to be policy relevant.
For example, governments have committed to prevent dangerous climate change, under the 1992 U.N. convention on climate change. They have agreed that staying below 2 degrees Celsius warming is a threshold for achieving that goal. They agreed to review next year whether the threshold might be lowered to 1.5C.
The findings of the latest IPCC report show serious impacts below 2C. These include research that some 90% of coral reefs would be lost at more than about 1.5C warming above pre-industrial levels.
And sustained warming of just 1C over the next two millennia would lead to 2.3 metres sea level rise, which would re-draw the map of the world. Sea level rise would increase to 4.8 metres for sustained warming of 2C.
Clearer messages
The IPCC, in its summary chapter at least, could make clearer statements by supplying such context, perhaps like this:
– Research shows that sea levels will rise by about 2.3 metres for 1C warming above pre-industrial levels, over the next 2,000 years.
– Sea levels are therefore on course to rise by at least 2 metres over the next two millennia, almost regardless of action now, given that temperatures have already risen by 0.85C.
– That assumes no great technological advance in absorbing vast quantities of carbon dioxide from the atmosphere.
– Governments have committed to 2C as a safe warming threshold, which would lead to an even more severe 4.8 metres sea level rise over the next 2,000 years, according to similar research.
– No country has prepared for such an amount. One study has shown that 1 metre sea level rise on the U.S. Gulf Coast would permanently flood a third of the region’s roads.
– Another calculated that for a 3 metre sea level rise, some 42% of all Pacific islands bigger than 2.5 hectares would vanish, or 3.9% of the total area of all islands including the Philippines.
“It’s perfectly in order for us to say if so and so happened, so and so outcome is going to take place,” the head of the IPCC, Rajendra Pachauri, told RTCC on Tuesday.
The IPCC has a chance to make clearer statements as it prepares its final synthesis report, to be published in October.