While it seems clear that he is using "trick" to refer to a change in algorithm to remove the nonsensical data after 1961 and "decline" likely refers to the quality of the data, the phrase has led some of the more extreme critics to conclude that a data-shaping plot was at work.
Referring to weather data from the last decade, another scientist wrote: "The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't."
While such insinuations of poor scientific practice have drawn the most attention, more damaging for climate scientists are e-mails which reveal the hostile, partisan, bunker-like atmosphere at the lab, which goes to ridiculous lengths to prevent even moderate critics from seeing any of the raw data.
In one e-mail, Prof. Jones wrote that climate skeptics "have been after the CRU station data for years. If they ever hear there is a Freedom of Information Act now in the UK, I think I'll delete the file rather than send it to anyone."
As it happens, Prof. Jones admitted earlier this year that he "accidentally" deleted some of the CRU's raw-data files, material that the centre says amounts to about 5 per cent of its collection.
Prof. Jones wrote of efforts to deter skeptics from having access to data: "We will keep them out somehow - even if we have to redefine what the peer-review literature is!" In another, he asks that several of his colleagues "delete any e-mails" about their work on the IPCC's 2007 report.
That sort of language has led many people, including climate scientists, to worry that the scientific findings of the centre have been undermined by scientists who see themselves as activists trying to prove a case rather than impartial arbiters of scientific fact.
As the political fallout escalated yesterday, it became apparent that it may take some time for climate scientists to repair their collective reputation.
In Australia, 10 shadow ministers in the opposition Liberal Party resigned in the wake of the revelations, in protest against their party's support for Australia's carbon-reduction bill.
In the United States, Republican Congressman James Sensenbrenner, leader of a climate-skeptic caucus, declared that the e-mails "call into question the whole science of climate change" and pledged to resist any climate bill.
And Saudi Arabia, the world's largest oil producer, announced that the e-mail leaks provide sufficient proof that climate change is not man-made that there should be no policy resulting from the Dec. 7-18 Copenhagen summit, in which the world's nations will try to negotiate a successor to the Kyoto Protocol.
"It appears from the details of the scandal that there is no relationship whatsoever between human activities and climate change," said Mohammad al-Sabban, the head of the Saudi Arabian delegation. "Climate is changing for thousands of years, but for natural and not human-induced reasons."
While some climate scientists have taken a defensive posture, the crisis has led a number of others to conclude that their approach to the subject needs to change.
Prof. Hulme leads a group of CRU scientists who believe that the extraordinary political importance placed on their research, and the activist, ideological way that research has been used by the IPCC, has put scientists in the position of being the authors of policy - a position that distorts the role of science in society.
"If we simply believe that science dictates policy, then I'm afraid we're living in an unreal world," Prof. Hulme said. "If people are arguing that science policy should flow seamlessly from the science, then science becomes a battleground, where people start saying that we must get the science on our side. We have lost an openness and a transparency that leads to good science."
Prof. Hulme is one of several scientists calling for the raw data of climate-change research to be made available to everyone, including climate-change skeptics, on the Internet. That, he says, would allow genuine research to proceed unhindered. Some of his colleagues also say the IPCC now does more harm than good and should be disbanded.
That position has led some of his colleagues to attack him. This week, several said in Internet posts that such transparency would be unworkable because the matter of climate is too urgent and the stakes too high to allow skeptics to have any influence on policy.
That, Prof. Hulme said, is exactly the attitude that led to the sort of questionable practices chronicled in the CRU e-mails.