"The equation is still a little bit tight, but demand is softening," Jackson said. "We just have to wait and see how those factors play out."
Hirsch, author of a widely cited 2005 Energy Department report on peaking oil output, sees a more urgent situation.
When he spoke at last month's energy summit, Hirsch said that large oil fields were emptying faster than expected, remaining reserves were overestimated and new finds and technology would offer only incremental additions.
"There's no question in my mind that we're likely to see oil production go into decline somewhere between 2010 and 2012," said Hirsch, senior energy advisor to Management Information Services Inc., an Alexandria, Va., consultancy.
His views reflect the core principle of "peak oil," a decades-old doctrine that holds that global crude production will crest sooner than expected and then begin a precipitous decline. Predictions about the timing vary: Some say we've already hit the peak, while others posit that it won't arrive for another decade or more.
Forecasting is a perilous business. Earlier peak oil predictions, including some from the 1970s supply crisis, missed the mark. Non-peakists have erred in production estimates. And nearly everyone failed to predict the leap in oil prices over the last year.
Geologists and others in the oil industry hotly dispute peak oil predictions, but an increasingly alarmed public has injected fresh momentum into the movement.
"Peak oil is percolating all over the place," a seismic shift from when peak oilists were considered the petro-world's "lunatic fringe," Hirsch said.
Websites devoted to the subject, such as the Oil Drum, have been proliferating. You can buy peak oil boxer shorts at one site and laugh at peak oil jokes on another.
Consultant Matthew Simmons, known in some circles as Mr. Peak Oil, said he is flooded with speaking requests and gets up to 30 Google alerts a day when his name pops up in a new item.
The boiling debate, in which peakists and their critics flay one another's conclusions and intelligence, is fed by imprecise terminology and oil-field data that are questionable or incomplete. For starters, views vary wildly on how much oil remains in Saudi Arabia -- crucial information for projecting worldwide supplies.
Birol, of the international energy group, hopes his November report will "move this debate from having fights in the Internet and e-mail domain, and from a personal domain, to a more objective and data basis."
