Climate costs

Ottmar Edenhofer must be an optimist. The climate expert has spent years warning people about the consequences of climate change as the chief ecologist at the Potsdam Institute for Climate Impact Research and as a member of the Intergovernment Panel on Climate Change.

But few countries have listened so far and his audience is getting smaller and smaller. Worldwide greenhouse gas emissions are increasing, and only a handful of countries adhere to the terms of the Kyoto Protocol, the only global climate treaty. Yet Edenhofer said he still believes in maintaining the goal of keeping the increase in global average temperature to two degrees Celsius by the year 2100.

"The two degree goal is reachable, but it will be a real challenge," he said.

The effects of a two degree increase in global temperature are what climate researchers have said could be handled by humans. Since industrialization in 1850, which scientists use as the temperature baseline, the average temperature has gone up by one degree Celsius.

The high price of delays

Edenhofer presented a study by his institute on Thursday (12.09.2013) showing that further delays in dealing with climate change would triple the costs that the international community would eventually have to bear.

Should a climate treaty be signed in 2015 during a conference scheduled to take place in Paris, global economic growth would fall by some two percent as countries spend money on measures to fight the greenhouse effect. Should countries delay taking action until 2030, it would hit global economic growth by seven percent, the study said.

That should give politicians some food for thought, according to Jochen Flasbarth, president of the German Federal Environment Agency. "Whether you are an optimist or a pessimist, there is no reason for a laissez-faire policy here," he said. "We can still take action and now is the time to do it."

Multiple solutions needed

Edenhofer wants to stick to the two degree goal with a set of steps some observers have called a pipedream. He has called for a global carbon dioxide trading system with prices between 20 euros and 50 euros ($26.50 to $66.35) per ton of CO2. He said use of fossil fuels will only decrease when it becomes more expensive than other energy sources. A regional market along the lines of Edenhofer's suggestion already exists in Europe; prices for a ton of carbon dioxide emissions currently cost about 3 euros.

Edenhofer said he believes countries will create a global CO2 market soon. "Even nations that do little for climate protection want a higher CO2 price because they need money for education," he said. "After the financial crisis, countries are short on funds and a new environment tax is in high demand."

In addition to promoting renewable energy sources such as wind and solar power, Edenhofer has also called for an increase in the use of biomass, the emissions of which would be isolated and stored in pockets deep below the Earth's surface.

Using plants as a source of energy, however, is controversial among researchers as it requires land and burns plants that could otherwise be used to feed people. Edenhofer, however, said biomass will be critical to keeping the increase in global temperature to 2 degrees or less. Equally important will be a new climate treaty, he added.

"No one will invest in it if countries are not forced to by a shared treaty," Edenhofer said. At the same time, he admits that he also thinks politicians lack the will to solve climate problems.

Some two years ahead of the Paris climate conference there are still no indicators as to what a binding climate protection treaty might include - or which countries would ratify it.