Scientific evidence that the world is getting warmer is “unmistakable,” according to a report by the National Oceanic and Atmospheric Administration drawing on research from 48 countries, including Russia and China.
The past decade was the warmest on record and the past 50 years have been getting hotter, the researchers said, citing 10 main indicators, including surface and ocean temperatures, the amount of sea ice and glaciers and levels of humidity.
“The records come from many institutions worldwide,” Jane Lubchenco, NOAA administrator and undersecretary of commerce for oceans and atmosphere, said in a statement. “These independently produced lines of evidence all point to the same conclusion: Our planet is warming.”
Globally, air temperature near the surface in the past 10 years was 1 degree Fahrenheit warmer than the 1960s and about 0.4 degree warmer than the 1990s, according to the report.
The warming has lead to shrinking glaciers, more heat waves and heavier rainfall as moisture in the atmosphere increases, the researchers said.
“The temperature of 1 degree Fahrenheit over the past 50 years may seem small, but it has already altered our planet,” said Deke Arndt, co-editor of the report, called “State of the Climate in 2009.” “And there is now evidence that over 90 percent of warming over the past 50 years has gone into our oceans.”
The researchers took into account the temperature of the atmosphere, the heat content of oceans, sea level, sea surface temperatures and snow cover. They also examined 27 other indicators, including greenhouse gas concentrations in the atmosphere, precipitation levels and salinity of the oceans.
The amount of humidity has risen, while glaciers, sea ice and snow cover have all shrunk, the report concluded.
“The scientific evidence that our world is warming is unmistakable,” according to the statement.
Arndt said he is alarmed by the amount of heat energy being absorbed by the ocean, 93.4 percent of all warming. Water holds heat better than air, so warmth will linger longer.
“It builds the momentum in the system,” Arndt said.
Evidence of ocean warming has been detected as deep as 6,000 feet below the surface, according to NOAA.
The authors of the report said people shouldn’t draw conclusions that all is well from periods of cool weather.
“A warming climate will still have cold spells, though they will become less frequent and less intense,” according to another NOAA statement. “For example, in the winter of 2009- 2010, a warm air mass moved into Canada and pushed cold air south. Canadians experienced a mild winter, but the mid-Atlantic coast of the United States was extremely cold and snowy.”
While snow records were set in the U.S. from Dallas to New York, the rest of the Northern Hemisphere had “one of the warmest winters on record,” the agency said.
More than 300 authors from 48 countries contributed to the report, according to a NOAA statement.
The data came from more than 7,000 weather stations, according to the report. The editors for the report come from the National Climatic Data Center, and the American Meteorological Society provides scientific reviewers and publishes it.
Some skeptics have said temperature measurements could have been skewed by weather stations being set up in more urban areas, and contend an accurate picture of the Earth’s warming can’t be measured.
Arndt said in a telephone interview the new report shows many indicators are backing up temperature measurements.
“It was quite striking to see that many voices singing in a single chorus,” he said.