• At the moment, it actually says nothing about a possible cosmic-ray effect on clouds and climate, but it's a very important first step.” This may be because he was ordered to speak circumspectly. According to science writer Nigel Calder, Rolf-Dieter Heuer, the director of the CERN lab, told a German newspaper that “I have asked the colleagues to present the results clearly, but not to interpret them. That would go immediately into the highly political arena of the climate change debate. One has to make clear that cosmic radiation is only one of many parameters.