NASA administrator Michael Griffin said in the closed-door meeting Monday at the Jet Propulsion Laboratory in Pasadena that "unfortunately, this is an issue which has become far more political than technical and it would have been well for me to have stayed out of it."
"All I can really do is apologize to all you guys ... I feel badly that I caused this amount of controversy over something like this," he said.
when he told a National Public Radio interviewer he wasn't sure global warming was a problem.
"I have no doubt that ... a trend of global warming exists," Griffin said on NPR. "I am not sure that it is fair to say that it is a problem we must wrestle with."
Griffin added: "I guess I would ask which human beings, where and when, are to be accorded the privilege of deciding that this particular climate that we have right here today, right now, is the best climate for all other human beings. I think that's a rather arrogant position for people to take."
The radio interview angered some climate scientists, who called his remarks ignorant.
An international panel this year predicted that uncontrolled greenhouse gas emissions could drive up global temperatures and trigger heat waves, devastating droughts and super storms. Observations by NASA satellites show evidence of rapidly melting glaciers and shrinking of critical marine plant life due to warmer seas.
Griffin reiterated that NASA's job was to provide scientific data on global warming and leave it up to policy makers to decide what to do with it.
Griffin told JPL workers he tried to separate his opinions during the NPR interview, but that it got "lost in the shuffle."
"Doing media interviews is an art. Their goal is usually to generate controversy because it sells interviews and papers and my goal is usually to avoid controversy," he said.