According to Stern, the current rate of greenhouse gas emissions will warm the world much more than the targeted 2 degree Celsius above preindustrial levels by the end of the century. Image: Flickr/CIAT International Center for Tropical Agriculture
Climate change looks far more threatening than it did six years ago as the world marches toward a warming of 4 degrees Celsius higher by the end of the century compared to the preindustrial era, said Lord Nicholas Stern, a professor of economics and chairman of the Grantham Research Institute at the London School of Economics.
Stern called for new and better climate models and better economic assessments of climate impacts but maintained that the main obstacle to action is political will.
The former World Bank chief economist was critical of his own 2006 review on the economics of climate change, a document considered seminal to climate change discussions, which estimated that the overall cost of climate change would shave off at least 5 percent of gross domestic product growth annually. Stern said that the review underestimated the "immense risk" from global warming. He made a similar admission and warning earlier this year at the World Economic Forum in Davos, Switzerland.
Speaking at the International Monetary Fund headquarters in Washington, D.C., Stern painted a gloomy picture of emissions being at the top end of the Stern Review projections, sea ice decline and ocean acidification occurring faster than anticipated, and growing impacts from feedbacks and tipping points not factored into climate models.
The current rate of greenhouse gas emissions will warm the world much more than the targeted 2 degree Celsius above preindustrial levels by the end of the century, according Stern. Even if nations stick to the emissions reduction commitments they made at the 2010 U.N. climate conference in Cancun, Mexico, temperatures will rise between 4 and 5 degrees, causing boundaries for deserts, coastlines and rivers to be redrawn. These issues of human welfare need to be factored into climate models, Stern said.
He drew on the example of climate models that predict a 20 percent loss in agriculture in India with a 4-degree-Celsius rise in temperature. The models do not factor in further deterioration due to loss of snow in the Himalayas that would lead to destruction of rivers or for radical changes in the south Asian monsoon. "Some of the questions we have to ask are what really affects human life -- extreme weather events, inundation, desertification. That's what affects human life," Stern said.
Also missing from current climate models are the lasting and dynamic impacts of extreme weather events. "Some close friends in Pakistan tried to describe to me with what happened in the floods in 2010. They said development was put back by 20 years. If you put back development by 20 years every 10 years, you are going backwards," he said.
Similarly, according to Stern, economic assessments underestimate impacts of climate change, place a modest price tag on carbon, and don't make room for loss of capital, labor and land in the future. The economic scenarios fail to recognize that future generations may be poorer and growth could be reversed, he said. He called the discussion of discounting in climate change "purely awful."
Another major failure of economic policies, he said, has been the pricing of hydrocarbons. "You cannot believe two things together -- that the price of hydrocarbons is right and the world has a 50-50 chance of holding to 2 degrees [Celsius]," Stern said.
The economist said that world has to make the transition to a low-carbon economy with innovation, investment and dynamism. "We have to see this alternative path as a new energy industrial revolution. We must divide emissions output by a factor of seven or eight," said Stern pointing to the fast-falling costs of solar energy technology as evidence that it can be done.
Technical progress is needed not only in alternative energy technology but in hydrocarbons, as well, and for developing other lower-emission bridge fuels, like natural gas, in the move toward fossil fuel-free economies, he said.