2005 Continues the Warming Trend
Friday, December 16, 2005
This year has been one of the hottest on record, scientists in the United States and Britain reported yesterday, a finding that puts eight of the past 10 years at the top of the charts in terms of high temperatures.
Three studies released yesterday differ slightly, but they all indicate the Earth is rapidly warming. NASA's Goddard Institute for Space Studies has concluded 2005 was the warmest year in recorded history, while the National Oceanic and Atmospheric Administration and the U.K. Meteorological Office call it the second hottest, after 1998. All three groups agree that 2005 is the hottest year on record for the Northern Hemisphere, at roughly 1.3 degrees Fahrenheit above the historical average.
Jay Lawrimore, who heads NOAA's Climate Monitoring Branch in its National Climatic Data Center in Asheville, N.C., called the new data "one of the indicators that the climate is changing." He added: "It's certainly something the administration is taking seriously."
The three teams used the same set of ocean and land temperature records, but they analyzed the data and compensated for gaps in the climatic record differently. As a result, NASA scientists estimate that 2005 average global land and sea temperatures were 1.04 degrees Fahrenheit above average, just beating out 1998's 1-degree elevation. NOAA researchers, by contrast, say this year's global average is 1.06 degrees Fahrenheit above average, compared with 1.1 degrees in 1998.
The analyses were based on data through the end of November and projections of December temperatures.
Scientists said yesterday that these differences should not detract from their common conclusion that the world is experiencing serious climate change, driven in part by human activity. Researchers recently found by drilling ice cores that there is a higher concentration of carbon dioxide in the atmosphere than in any time in the last 650,000 years, which reflects that humans are burning an increased amount of fossil fuels to power automobiles and utilities.
The Earth has warmed 1.4 degrees Fahrenheit in the past century, with 1 degree of this increase occurring in the past 30 years. This climate change has brought unusually prolonged droughts in some regions and heavy precipitation in others, while the Arctic's sea ice has shrunk to its lowest level since observers started using satellite records in 1979.
James Hansen, who directs NASA's Goddard Institute, said this year's statistics were particularly significant because in 1998 the world experienced El Nio, which drove up temperatures dramatically. This year, by contrast, the world reached record levels without such a dramatic climatic event.
The world's temperatures are on an upward trend, Hansen wrote in an e-mail, "because it is being driven by the Earth's present energy imbalance, which is substantial." As long as humans keep adding more heat-trapping greenhouse gases, Hansen added, "the planet stays out of energy balance."
Some global-warming skeptics questioned the significance of yesterday's findings. "Saying that 2005 was a near-record is like saying that a plane that landed safely could have crashed," said William O'Keefe, chief executive officer of the George C. Marshall Institute. "It is trying to make news where none exists."
But Climate Policy Center Chairman Rafe Pomerance, whose bipartisan group backs mandatory limits on emissions of carbon dioxide, disagreed. "The temperature trend is a wake-up call for the Congress and the president to craft a response that will begin to dramatically reduce the buildup of greenhouse gases in the atmosphere," he said.