2001 the 2nd warmest year on record

It's official: The new millennium is hot.\nWith final December numbers now in, 2001 ranked as the second warmest year on record on planet Earth, according to the government's National Climate Data Center.\nFor all those fretting over global warming and the end of snow as we once knew it, this is disturbing. The five warmest years since record-keeping began in 1880 all occurred after 1990. In the other four years - including the warmest, 1998 - strong El Ninos, significant warming of surface waters in the tropical Pacific, contributed to the high temperatures.\nNot this time.\n"It was a little surprising to see it was that warm," said Jay Larimore, a scientist at the climate center in Asheville, N.C.\nThe climate center's worldwide network of surface stations measured an increase of 0.9 degree worldwide in 2001. With a surprisingly balmy December, it was the sixth-warmest year ever for the United States.\nEarth's annual temperatures have been above long-term averages for 25 years running, according to the climate center's data. In that period, the government estimates that the global temperature has risen at a rate equal to 3 degrees per century. \nOn the surface, this might seem to ice the case for human-abetted global warming and put the great warming debate to rest once and for all.\nBut this debate is nothing if not restless. And once again, evidence collected from outer space has challenged the climate center's findings from the ground.\nNASA satellite observations, which calculate temperatures for the bottom 5 miles of the atmosphere, did find some warming last year, but far less than the global network of surface stations. Based on the 23 years for which data are available, the satellite's estimated rate of warming was a mere 1.2 degrees per century, according to NASA scientists Roy Spencer and John Christy.\nEven given the absence of El Nino, Christy was unimpressed with the 2001 level of warming.\n"The warming has been very minor," he said. In 1980, he pointed out, another year without El Nino, the satellite found about twice as much warming as it did last year.\nAs he has for several years, Christy argued that the surface network has serious gaps over the vast oceans and deserts.\nWhile admitting shortcomings, keepers of the surface databases counter that outer space is not the best place to measure temperatures on Earth. And they say they have been able to make allowances for data gaps.\nLarimore - the surface guy - said the case for human-enhanced global warming isn't closed. The planet's temperature has been rising for at least 18,000 years, since the end of the last ice age, and long before the first smokestacks. The measured warming in the last 120 years has occurred unevenly. But he's convinced the trend is real, if not scary. \n"Certainly, there's long-term and short-term variability," said Larimore, "but over the long term the temperatures have been rising"