08/07/2018

Climate Change Will Get A Whole Lot Worse Before It Gets Better, According To Game Theory

WiredRoger Highfield

A firefighter douses flames from a backfire in San Andreas, California. Getty Images / JOSH EDELSON / Stringer
It’s going to get a lot worse before it gets any better.
According to new research published in Nature, humanity will witness marked sea level rises and frequent killer heatwaves before governments take decisive action against climate change.
And to predict the future, mathematicians have turned to game theory.
The paper, published by a team of mathematicians, uses game theory to explain why it is so hard to protect the environment, updating it so they could model the effects of climate change, overuse of precious resources and pollution of pristine environments.
The bad news is that the model suggests that, when it comes to climate change, things might have to get demonstrably worse before they can get better.
The good news, on the other hand, is that game theory could help policymakers to craft new and better incentives to help nations cooperate in international agreements.
The researchers used one of the best known social dilemmas in game theory — called the tragedy of the commons — to reach their predictions. The tragedy of the commons was first described in the 19th century by William Forster Lloyd, an Oxford University political philosopher. Lloyd analysed the overuse of common land (also known as a "common") by people who had rights to use it — to graze their sheep, for example — to air the idea that resources that do not clearly belong to an individual or a group are likely to be overexploited, since conserving them isn’t in the interest of the individual.
The idea was later made famous by American ecologist Garrett Hardin, in a 1968 paper published in the journal Science. The tragedy of the commons has become one of the most used metaphors among experts to illustrate our chronic inability to sustain a resource that everybody is free to use and, alas, just as free to abuse.
We see examples of this dilemma in our daily lives, from litter on the subway to the reluctance to empty the dishwasher in the shared student kitchen. The most extreme example, however, is the current environmental crisis.
Previous attempts to come up with a mathematical model of the environmental tragedy made the unrealistic assumption that the commons remained unchanged as people exploited them – they played the same game in every round of the model. These approaches could not study the effects of a degrading environment, such as an increasingly overfished sea or a river as it was being polluted, for example. In their new Nature paper Martin Nowak of Harvard University, working with Christian Hilbe and Krishnendu Chatterjee of the Institute of Science and Technology Austria, and Stepan Simsa of Charles University in Prague, detail a more faithful way to model – and understand - the dilemma with mathematics.
“It is based on the simple idea that our actions today change the game we can play tomorrow,” Nowak says. The games in question involve encounters between people where they can either work together and cooperate or pursue their own selfish motives instead. “Depending on what you and I are doing, we move to another game so, as an example, you and I write an article together and, if we do well, we may do a book and, if this continues, we might set up a research institute.”
When they explored the new mathematical model, the scientists found that this dependence on players’ actions could greatly increase the chance that players cooperate, provided the right conditions were in place. “We have shown how environmental feedback can spur cooperation,” says Nowak, who has spent decades exploring the laws of cooperation.
These feedback factors include how quickly our resources — be it the ocean or the planet’s ozone layer — degrade. This might explain why relatively rapid action to ban chemicals such as chlorofluorocarbons were prompted when a dramatic drop in atmospheric ozone that protects life from the Sun's harmful UV rays was detected by a British team working in Antarctica in 1985. A global agreement to protect the stratospheric ozone layer, the Montreal Protocol, was finalised in 1987 and went into force a couple of years later.
This is not the case with climate change. Although we know that glaciers are shrinking, sea levels are rising, and extreme weather events — from hurricanes to heatwaves — are becoming more intense, these effects are often complex and occur over longer timescales, so establishing a clear link between them and climate change is less straightforward. This, according to Nowak, might explain why it has been more difficult to come up with effective international cooperation to curb climate change driven by greenhouse gases.
The new mathematical model suggests the global environment has to deteriorate in a dramatic way – hurricanes becoming more intense, more droughts and heatwaves – before our eyes before governments will be spurred on to make things better. “When human activity leads to drastic environmental deterioration, through global warming, cooperation becomes the winning strategy,” Nowak says.
However, this new mathematical model also enables policymakers to explore future possibilities raised by climate models and explore next steps on a more rational basis. “This opens up many new possibilities,” says Nowak. Because key impacts of climate change occur over a long timescale, one option is not to rely on environmental decline to spur policymakers into action. Instead we need to devise incentives that work over much shorter timescales, say a year or so. “We even show which feedback is needed,” Nowak says.
“You could give people, cities or countries financial incentives to work together on a problem and, if they succeed, they get these incentives and can move to bigger and more complex problems, along with even larger rewards.” The financial incentives hinge on the actions of the players, whether they are people or countries. “Cooperation leads to more valuable games, defection to less valuable ones, and can be designed to occur quickly enough to make a difference,” Nowak says. “This new approach is a game changer.”

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Why Climate Change Is A Security Matter

World Resources Institute


Mopti riverfront
Photo by Mark Abel/flickr
On a satellite map of Mali, the Inner Niger Delta looks like a giant green smudge on a beige, sandy background.
It is remote, remarkable and a reminder of the complex interplay between some of the biggest issues facing Europe and climate change.
The delta itself is lush, blessed with a water supply from the Niger River that has turned this part of the semi-arid Sahel into a veritable oasis.
But it is also vulnerable.
The natural balance between its people, its ecosystem and the waters that give it life can easily be upset, with shockwaves reaching as far away as Europe. In the Netherlands, which is grappling with issues such as security and migration, the Niger Delta is a reminder of the irrevocable links between these issues and the impact of climate change.
The Sahel is no easy place to live, sandwiched between the blank expanse of the Sahara desert and the fertile coast of West Africa. The Inner Niger Delta stands out against the rest of this water-scarce region, fed by the great Niger River. It rises in the hills of Guinea before describing a giant crescent through Mali, Burkina Faso and Niger, then down to Nigeria and its outlet on the Gulf of Guinea.
During its passage through Mali, something remarkable happens: not long after the regional capital of Mopti, the river splits, spreading out across the land in a myriad of channels, many of which sink into the earth as though absorbed by a sponge. As it leaves this landlocked delta, it regathers as a more regular river for the remainder of its journey.
Unsurprisingly, the watery wealth of this delta region has a profound impact on the landscape and its people. It supports a wealth of small-scale agriculture and fishing, with countless villages and settlements on tiny islands in between the channels. But the balance that sustains the delta is a fine one, and several factors make it complicated.

At the Edge of the Sahara
Up on the edge of the Sahara are the bases of Al Qaeda in the Islamic Maghreb (AQIM), and training bases for the international coalition – including Dutch soldiers and police - that is combatting it. These insurgents are known to target delta communities, which are themselves being disrupted by discord between generations: ubiquitous mobile phones have contributed to a younger generation of delta residents becoming dissatisfied with the lives led by their elders.
Indeed, many migration routes from West Africa to Europe cut through the region, bringing the influence of the trafficking gangs. Upstream, dam projects in Guinea and Mali itself threaten to disrupt the flow of the Niger into the delta. Meanwhile, water-hungry commercial agriculture for crops such as sugar cane has arrived, funded by outsiders including the Chinese. And then there is the climate.
Few things have the capacity to disturb the balance of the Inner Niger Delta as much as climate change. Rising temperatures could destroy livelihoods, threaten the Malian economy and turn more people towards escape routes – whether to urban slums, migration routes north to Europe or the ranks of AQIM. Places like the Inner Niger Delta are ground zero for climate change. What happens there will also affect what happens in Europe.
The danger is evident, but what can be done about it? The first step is to recognize these critical linkages. That is why I recently attended a High Level Conference on Climate, Peace and Security in Brussels, convened by the Head of the European External Action Service, Federica Mogherini. One area that was discussed was the role of data in helping us understand what is happening in places like the Inner Niger Delta, and the complex interplay between natural and human factors.
World Resources Institute is currently one of the partners involved in a project called the Water, Peace and Security initiative, funded in part by the Dutch Ministry of Foreign Affairs. It is aimed at combining data to produce an early warning system. Elsewhere, measures such as infrastructure spending or financial tools can be part of the solution. But these only serve to mitigate or warn about the problem.
The second step, then, is more familiar. We must continue – and increase – our efforts to slow down man-made climate change. Instead of thinking about a bald figure like 2 degrees Celsius (3.6 degrees Fahrenheit), think of the impact of global warming in places like the delta. This underlines the urgency of our shift to a low-carbon circular economy.
This is not just about signing off on international commitments or future competitiveness, but our own fundamental security interests: the sustainability of vulnerable regions like the Inner Niger Delta is as critical for our own security as it is for those who call those places their home.

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Global Temperature Rises Could Be Double Those Predicted By Climate Modelling

The Guardian

Researchers say sea levels could also rise by six metres or more even if 2 degree target of Paris accord met
Researchers say temperature and sea level rises could be much more extreme than previously believed. Photograph: Tracey Nearmy/AAP
Temperature rises as a result of global warming could eventually be double what has been projected by climate models, according to an international team of researchers from 17 countries.
Sea levels could also rise by six metres or more even if the world does meet the 2 degree target of the Paris accord.
The findings, published last week in Nature Geoscience, were based on observations of evidence from three warm periods in the past 3.5m years in which global temperatures were 0.5-2 degrees above the pre-industrial temperatures of the 19th century.
The researchers say they increase the urgency with which countries need to address their emissions.
The scientists used a range of measurements to piece together the impacts of past climatic changes to examine how a warmer earth would appear once the climate has stabilised.
They found sustained warming of one to two degrees had been accompanied by substantial reductions of the Greenland and Antarctic ice sheets and sea level rises of at least six metres – several metres higher than what current climate models predict could occur by 2100.
“During that time, the temperatures were much warmer than what our models are predicting and the sea levels were much higher,” said Katrin Meissner from the University of New South Wales’s Climate Change Research Centre and one of the study’s lead authors.
She said the effects today would mean populous urban areas around the world and entire countries in the Pacific would be underwater.
“Two degrees can seem very benign when you see it on paper but the consequences are quite bad and ecosystems change dramatically.”
Meissner said potential changes even at two degrees of warming were underestimated in climate models that focused on the near term.
“Climate models appear to be trustworthy for small changes, such as for low-emission scenarios over short periods, say over the next few decades out to 2100,” she said. “But as the change gets larger or more persistent ... it appears they underestimate climate change.”
The researchers looked at three documented warm periods, the Holocene thermal maximum, which occurred 5,000 to 9,000 years ago, the last interglacial, which occurred 116,000 to 129,000 years ago, and the mid-Pliocene warm period, which occurred 3m to 3.3 m years ago.
In the case of the first two periods examined, the climate changes were caused by changes in the earth’s orbit. The mid-Pliocene event was the result of atmospheric carbon dioxide concentrations that were at similar levels to what they are today.
In each case, the planet had warmed at a much slower rate than it is warming at today as a result of rising greenhouse gas emissions caused by humans.
“Observations of past warming periods suggest that a number of amplifying mechanisms, which are poorly represented in climate models, increase long-term warming beyond climate model projections,” Prof Hubertus Fischer of the University of Bern, one of the study’s lead authors.
“This suggests the carbon budget to avoid 2°C of global warming may be far smaller than estimated, leaving very little margin for error to meet the Paris targets.”

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