Steaming black-guy heads, the traditional sign of approaching winter for generations of football fans, have been occurring later in the season with every passing year, a fact that may be evidence of a climatic change with long-term effects on football itself, top scientists in the meteorological department of the National Football League said in a study released Monday. 'The phenomenon of weather-related African-American supracranial vaporous emission, or 'Steaming Black-Guy Heads,' as it is colloquially known, occurs when cold dry winter air comes into contact with hot, humid, shaven heads of football players, causing their personal water vapor to condense and rise on a column of heated air,' the statement read in part. 'It is then observed by network cameramen, who overwhelmingly choose to film African-American players due to the dramatic contrasts that resultespecially when the player in question is backlitand beamed to millions of households during time-outs, replay reviews, and other stoppages of play. The viewers then realize that winter has come to America.' 'However, film review reveals that steaming black-guy heads, which during the 1970s were commonplace in mid-September, have in recent years not been sighted until the weeks after Thanksgiving,' the statement continued. 'Although further study is definitely called for, we conclude that the pronounced trend for steaming black-guy heads to occur progressively later every yearcoupled with the phenomenon of giant triangles of ass-sweat persisting well into Novemberis a possible indication of a slowly warming climate across the entire NFL.' League commissioner Roger Goodell was not available for comment, saying that, although early-season instances of steaming black-guy heads were obviously preferable, the NFL had no official stance on climate change, global warming, or other meteorological phenomena that did not directly affect the scheduling or outcome of games. Reaction among coaches and players has been mixed. 'When I came into the league with Tampa Bay, steaming black-guy heads were everywhere in October,' said longtime NFL veteran and current Carolina Panthers quarterback Vinny Testaverde. 'The Bucs were in the NFC Central back then, and we played in Chicago and Green Bay a lot, and to me, they always meant Halloween was coming. But these days, the rookies think of them as the first sign of Christmas. You can't tell me that's not global warming.' 'Early on in my career, I saw them a lot, even in September,' said Packers quarterback Brett Favre, who still has fond memories of the steaming heads of such Packer greats as Sterling Sharpe, LeRoy Butler, and Reggie White. 'But this year we only started getting them just this week, and it's December already. Listen, I don't know anything about climate change, but I'd hate to see my daughters grow up in a world where steaming black-guy heads are just something you see on ESPN Classic.' NFL climatologist Lee Orfordson, one of the authors of the report, advised caution among those worried about the dwindling instances of steaming black-guy heads around the league. 'Remember that there are more domed stadiums now, that Northern-tier teams are being scheduled for more away games in Southern-tier cities during the winter months, and above all, that steaming black-guy heads are a single, if dramatic, phenomenon,' Orfordson said. 'There are plenty of numbers still to crunch here before we can say the steaming black-guy head has gone the way of the dodo.' Still, for generations of fans for whom steaming black-guy heads were an important symbol of seasonal change, the announcement has inspired a definite feeling of foreboding. 'I was the very first of the steaming black-guy heads,' said former Raider defensive end Otis 'The Grandfather Of All Steaming Black-Guy Heads' Sistrunk, whose own vigorously steaming head was noted by ABC color man Alex Karras in the early autumn of 1974 and began a winter-onset sideline-camera tradition that continues to this day. 'And I'm very, very proud of that. I just hope I don't live to see the last.' 