During the 1980s and 1990s, global high-temperature records have been broken every few years. But this year has broken all records for record-breaking. "Each month has bested the previous record by a substantial amount," says Kevin Trenberth, senior scientist in NCAR's Climate and Global Dynamics Division. "And this follows on the heels of 1997's being the warmest calendar year on record." The top figure shows the amounts by which each month this year has overtaken the previous high and the year in which the earlier record was set.
The values for 1998 are running 0.25 degrees C above last year's, which were already about 0.75 degrees C above those for the last century. "If [the trend] continues, this would put 1998 at 1 degree C above the last century," Trenberth notes. The bottom figure shows the rise in this century's global temperature anomalies and the high jump to this year's increase.
Even if 1998 turns cooler, we are still undergoing global record-breaking heat. A recent study by Michael Mann, Raymond Bradley (both of the University of Massachusetts), and Malcolm Hughes (University of Arizona) indicates that the last ten years were the warmest in at least the past 600 years, which is as far back as a global estimate of temperatures can be made.
For more information on global 1998 temperature records, visit the National Climatic Data Center's
on this year's extremes. (Top figure from NCDC; bottom figure courtesy of Kevin Trenberth.)
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Edited by Carol Rasmussen,
Prepared for the Web by Jacque Marshall
Last revised: Tue Apr 4 15:03:21 MDT 2000