The disclosure of personal emails can be embarrassing. And so it proved this week when hundreds of them, accumulated over more than a decade in the files of the Climatic Research Unit (CRU) of the University of East Anglia, UK, tumbled into the public domain as a result of an illegal hack.

Climate change deniers claim that the emails expose a conspiracy at work to make human-induced global warming a fact. A columnist for the Guardian newspaper in London said that the emails could scarcely be more damaging. One blog for the Daily Telegraph, also in London, called it “Climategate: …