"NOAA public affairs called and asked what I would say to certain questions, like is there a trend in Atlantic hurricanes. I said I thought there was a possibility of a trend emerging that tropical hurricanes were becoming more intense. They turned down that interview," Knutson said to the newspaper.
"It was not that he was denied it," St. John said to ABC News.
"It's part of the role of public affairs officers to try and match reporters up with the right experts," and Knutson was probably not the right expert to talk to CNBC, he said.
NOAA officials said that interview requests were routinely sent to the Commerce Department, and that nothing should be read into Fuqua's request that Knutson not do the interview.
"All media activities are reported in one manner or another," St. John said. "It [is] a general policy for any major issues -- regardless of what they are -- to be communicated … not only to the Department of Commerce but to NOAA leadership so they can know what the general media interest is."
"We're very proud of our scientists and the great work they do," said Commerce Department spokesman Richard Mills. "The role of our public affairs office, like other organizations, is to ensure that the media get accurate, timely and thourough information and that other officials are aware of what's being said so there are no surprises."
The science linking global warming to more powerful hurricanes has been the subject of intense scientific study and growing consensus over the last year.
Last week, a team of 19 top climate scientists from government labs in the United States and Europe reported that the buildup of human-induced greenhouse gases in the atmosphere appeared to be the primary driving force behind warmer oceans that fuel more powerful hurricanes.
Knutson was not connected to the latest study but was asked by ABC News to comment on it last week.
"We're increasing greenhouse gases and forcing the climate system in ways that we expect there are going to be very substantial changes in the coming century," he said. "We're trying to figure out what it means in terms of weather and things that impact people day to day, such as storms and heat waves and droughts."
The incident with Knutson echoes a similar recent attempt by administration officials to muzzle another government scientist who spoke out about global warming.
In January, NASA's top climate scientist, Dr. James Hansen, complained that political appointees were trying to limit his interaction with reporters after he gave a speech warning that greenhouse gases were bringing the planet's climate system to a "tipping point."
"One threat was relayed to me that there would be 'dire consequences', not specified," for speaking out, Hansen told ABC News.
A 24-year-old political appointee, George Deutsch, eventually resigned over the incident, and the agency issued a new communications policy that stressed openness among scientists and the news media. NOAA has been a previous target of criticism.
The editor of the journal Science alleged in February that NOAA scientists were not allowed to speak to reporters without approval.
Administrator Conrad Lautenbacher responded in an e-mail to NOAA staff, encouraging scientists to speak "freely and openly."
"I am a strong believer in open, peer-reviewed science, as well as the right and duty of scientists to seek the truth and to provide the best scientific advice possible," he wrote.
Waxman's letter requests "all internal documents or communications that describe or discuss the administration's position regarding the scientific issue of the connection between global warming and hurricanes" from Aug. 1, 2005, to the present.
He also asks Gutierrez to explain by Oct. 9 "the role of your office in determining which scientists could speak with the press regarding global warming."
For more on Rep. Waxman's letter, the e-mail exchange between NOAA and Commerce officials, and the NOAA Daily Media Tracking Log, Click here