The top few thousand feet of the ocean waters have increased in temperature by about one-tenth of a degree. The new studies tie in the observed effects on the ocean temperatures with those of the land and the atmosphere. The computer models mathematically express the effects of various elements of the climate. The researchers found that the computer models precisely matched the observed temperature rises only when factoring in the greenhouse gases added to the atmosphere by man-made activities, said Levitus. Levitus said the new models are more accurate than earlier studies because they include effects of the oceans.
Oceans tend to absorb some of the heat from the atmosphere.
A study last year by Levitus, based on hundreds of water temperature measurements, showed that the ocean has warmed since 1955. Global warming has been blamed for a number of climate effects, including the melting of mountain glaciers, shrinkage of polar ice caps, increases in storms and seasonal changes in flowers and plants. Critics contend, however, that these effects are part of the natural climate variation of the planet and are not caused by human influences. It presents in-depth information on the causes and effects of global warming. Register for the Hypography Sci-Tech newsletter Get free news and science info every week.