IPCC Lead Author Says Climate Models Are Failing

Published June 24, 2013

United Nations Intergovernmental Panel on Climate Change lead author Hans von Storch told Der Spiegel that climate models are having a difficult time replicating the lack of global warming during the past 15 years.

“So far, no one has been able to provide a compelling answer to why climate change seems to be taking a break,” said Storch

Storch said the models say the planet should be warming much more than it has.

“According to most climate models, we should have seen temperatures rise by around 0.25 degrees Celsius (0.45 degrees Fahrenheit) over the past 10 years. That hasn’t happened. In fact, the increase over the last 15 years was just 0.06 degrees Celsius (0.11 degrees Fahrenheit) — a value very close to zero,” Storch observed. “This is a serious scientific problem that the Intergovernmental Panel on Climate Change (IPCC) will have to confront when it presents its next Assessment Report late next year.

Storch explained that IPCC may have to revise its climate models to reflect real-world climate conditions.

“At my institute, we analyzed how often such a 15-year stagnation in global warming occurred in the simulations. The answer was: in under 2 percent of all the times we ran the simulation. In other words, over 98 percent of forecasts show CO2 emissions as high as we have had in recent years leading to more of a temperature increase,” Storch noted.

“If things continue as they have been, in five years, at the latest, we will need to acknowledge that something is fundamentally wrong with our climate models. A 20-year pause in global warming does not occur in a single modeled scenario. But even today, we are finding it very difficult to reconcile actual temperature trends with our expectations,” Storch explained.