Earth may be close to the warmest it has been in the last million years, especially in the part of the Pacific Ocean where El Nino weather patterns are born, climate scientists reported on Monday.

Earth may be close to the warmest it has been in the last million years, especially in the part of the Pacific Ocean where El Nino weather patterns are born, climate scientists reported on Monday.

This doesn't necessarily mean there will be more frequent El Ninos, but could well mean that these wild patterns will be stronger when they occur, said James Hansen of NASA's Goddard Institute for Space Studies.

The El Nino phenomenon is an important factor in monitoring global warming, according to a paper by Hansen and colleagues published in the current Proceedings of the National Academy of Sciences.

El Ninos can push temperatures higher than they might ordinarily be. This happened in 1998 when a so-called "super El Nino" helped heat the Earth to a record high.

What is significant, the scientists wrote, is that 2005 was in the same temperature range as 1998, and probably was the warmest year ever, with no sign of the warm surface water in the eastern equatorial Pacific typical of an El Nino.

The waters of the western equatorial Pacific are warmer than in the eastern equatorial Pacific, and the difference in temperature between these two areas could produce greater temperature swings between the normal weather pattern and El Nino, they wrote.

They blamed this phenomenon on global warming that is affecting the surface of the western Pacific.

(Agencies)