Climate change is a political science, and a messy one at that. This issue of Nature includes overviews and opinions that shed light on how researchers and citizens are responding to the regional effects of climate change. But at any level, the field is beset with genuine scientific uncertainties and complexities. Politically, these challenges are compounded by confusion on the part of the public and manipulation by sceptics of global warming.

The United States, of course, is rife with both confused citizens and vocal sceptics. But it is also home to many of the world's leading climate scientists, and they are involved in a major attempt to take the lead in this arena — an effort that now seems, unfortunately, to be foundering.

This week the US Climate Change Science Program held a workshop to assess its progress so far, and to look ahead to its future goals. The programme is supposed to produce 21 reports summarizing various aspects of climate science (see Nature 436 890; 2005). These should represent the best consensus that science can offer, and are due to be signed off by the US government, with the White House being the final step in the approval process. But if the brief history of the project's first report is any guide, the exercise will be lucky if it ever reaches fruition.

Climate researchers had hoped that this week's meeting would showcase the science coming out of the first report, on temperature trends in the troposphere. The report had successfully undergone review by the National Research Council and was about to be posted on the web for 45 days of public review. After that, with any changes duly incorporated, it would be sent to the White House for approval.

One congressman summoned novelist Michael Crichton to testify as a ‘scientific’ witness on climate change.

But this autumn, almost two years after they began work on the report, the authors were informed of a fresh requirement — that they be approved as governmental advisers under the terms of the Federal Advisory Committee Act. In theory, this extra layer of bureaucracy is meant to ensure the legitimacy of those who act as advisers. In practice, it meant that the climate scientists were fingerprinted and had their financial backgrounds checked. During this process, the report's authors were not supposed to speak to each other for several months, while their report languished.

Meanwhile, internal bickering broke out into the open. Group member Roger Pielke, a climatologist at Colorado State University, withdrew from the panel, claiming that his views that land-use changes contributed substantially to climate change were being suppressed (see Nature 437, 9; 200510.1038/437009a).

Even under such conditions, science will out. Three papers based on the tropospheric temperature report have already been published in Science (doi:10.1126./science.1114772; doi:10.1126./science.1114867; doi:10.1126./science.1115640; 2005). The researchers are now obtaining clearance to act as governmental advisers. And on 16 November, the three lead authors of the Science papers were due to discuss the findings at a seminar being held for congressional staff by the American Meteorological Society in Washington DC.

One of the researchers, climate modeller Benjamin Santer of Lawrence Livermore National Laboratory, had not been on Capitol Hill for a decade. In 1995 he was subjected to severe and unjustified criticism for his participation in that year's report from the Intergovernmental Panel on Climate Change — its first report to state that humans were having a discernible effect on the climate. Santer became the target at which climate sceptics took aim.

Santer's willingness to return to the fray is commendable. Global-warming sceptics still hold far too much sway in Washington, where one congressman earlier this year summoned novelist Michael Crichton to testify as a ‘scientific’ witness on climate change because of his pseudoscientific novel State of Fear.

In the face of such attitudes, researchers must stay the course. The government needs to streamline and accelerate the flow of information through the climate-change programme. The Bush administration owes the US public that much at least.