How Hot Was It?

Last month was the hottest September on record, making nine consecutive months of record heat.

Many scientists believe chemicals added to the atmosphere may be warming the planet. Others point to regular cycles of climate change over past years and note that accurate temperature records go back only about a century.

The National Oceanic and Atmospheric Administration reported Wednesday that the average worldwide temperature for the month was 59.98 degrees Fahrenheit, 1.08 degree above the 1880-1997 global average of 58.9 degrees.

"The recent string of unusually high global average temperatures could be a sign of accelerated global warming," said Thomas Karl, director of the NOAA's National Climatic Data Center in Asheville, North Carolina. "However, these records will not continue indefinitely because of the impacts of normal climate variability."

The recent warm months also have been blamed on the heating of the Pacific Ocean in the El Nino phenomenon, but that is now easing, the NOAA reported.

The climate center also reported that average temperatures in the contiguous United States beat the record heat during the Dust Bowl years of the 1930s.

Preliminary data indicate that September had a national average temperature of 69.1 degrees Fahrenheit, surpassing the previous record of 68.4 degrees, set in September 1931. The 1961-1990 normal temperature for the United States during September is 64.8 degrees.