I would like to share with you some impressions from a remarkable event taking place today and tomorrow in Potsdam: 15 Nobel laureates are meeting with top climate and energy experts and politicians to discuss global sustainability. You can follow the event with its presentations here, with a couple of hours of delay.
After opening remarks by PIK director John Schellnhuber, the IPCC chairman Rajendra Pachauri presented an overview over the main findings of the latest IPCC report. Nobel laureate Mario Molina drew interesting parallels of the current situation with the ozone hole issue and the Montreal Protocol to protect the ozone layer, that came into force in 1986. “The scientific findings are clear: climate is changing, and it is a response to human activities,” Molina said. He also noted that the Montreal Protocol, as a side effect, has bought us about 10 years time in the climate issue, because the now banned CFC’s also have a greenhouse effect in addition to damaging the ozone layer.
Next speaker was the German Chancellor Angela Merkel, herself a theoretical physicist by training. She pointed out that inaction on the climate issue would be at least five times more costly than reducing emissions, and she called for a reduction of global emissions by 50% by the year 2050. She reaffirmed that the European Union has pledged to reduce its emissions by 30% by the year 2020 if others join in, and that the target of the German government is a 40% reduction by 2020.
Next to speak was Sir Nicholas Stern, who explained the CO2 problem as a “flow-stock” problem – our emissions continually add to the stock of carbon dioxide in the atmosphere, making climate stabilisation at a certain level more costly the longer we wait. Delaying climate action by 30 years would make it 3 times more expensive. He also spoke about the ethical problems – “economists shy away from the ethics”, he said, but they need to be discussed.
This was a good lead to Nobel laureate Wangari Maathai (peace prize 2004) who joined by video link from Nairobi. She presented a passionate plea to preserve forests and plant a billion trees, and spoke of “carbon justice” in the relationship of the developed and developing world.
Several physics and chemistry Nobel laureates highlighted the tremendous potential of solar power for solving the world’s energy and climate problems. Carlo Rubbia (NP physics 1984) pointed out that a square of the size 210 x 210 km receives as much solar power as the whole world consumes in energy today. This is just a small pixel on the world map he showed, and just 0.13 % of the world’s desert area. Walter Kohn (NP Chemistry 1998) reported from a meeting in China a few weeks ago, presenting a number of interesting facts, such as that the solar cell production in China is growing at a rate of 40% per year. Alan Heeger (NP chemistry 2000) presented an inspiring lecture on cheap plastic solar cells – his lab is working on solar cells that can literally be printed on a roll of plastic sheeting, from a polymer solution. Present status is that they achieve an efficiency of 6.5 % with these printed solar cells, with much promise for rapid improvements.
I must stop now or I will miss the evening reception starting this minute. Tomorrow the event continues with a speach by the German environment minister on “The road to Bali”, and further scientific discussions. Join the video stream if you are interested!