Democrats in Congress Tuesday accused the Bush administration of censoring information about just how serious global warming is. There is broad scientific consensus about global warming, but testimony Tuesday by scientists strongly suggests that the Bush administration has made a concerted effort to suppress it.

ABC News

There aren't many skeptics left in the federal scientific community about global warming.

"The scientific evidence indicates that the earth is now warmer than at any time during the last thousand years," said Dr. Drew Shindell, NASA.

But Shindell told a House committee that in 2004, when NASA tried to report that a hotter planet meant eventual droughts and floods from rising sea levels, Shindell told them, "This release was repeatedly delayed altered and eventually watered down."

Others testified that the White House barred agencies from referring to the national assessment of climate change.

"This report has been made to vanish by the Bush administration," said Rick Piltz, former senior official with the U.S. Climate Change Science Program.

Two private groups surveyed nearly 300 federal climate scientists and found about half were told to delete the term global warming from studies.

"Political interference is harming federal science and threatening the health and safety of Americans," said Dr. Francesca Grifo, Scientific Integrity Program for the Union of Concerned Scientists.

Democrats charge that the effort to downplay global warming was led by a former White House official with ties to the oil industry.

"The Bush administration has shown a blatant disregard for the health of the American people. They have shown they would rather safeguard the interest of big oil than preserve the future of the planet," said U.S. Rep. William Clay, (D) Missouri.

Administration officials were not invited to testify leaving Republicans on the defensive.

"The idea that this administration has stymied inquiry and action is hard for me to swallow," said U.S. Rep. Bill Sali, (R) Idaho.

"Global warming is not a secret hidden from the people by the government," said Rep. Darrell Issa, (R) California.

White House officials have repeatedly said they have only tried to inject balance into reports on climate change.

The hearings in Congress come ahead of a much anticipated report on global climate change. This week 500 scientists are gathering in Paris to finish a United Nations report on how warming will affect sea levels.