Global Warming May Cause Stronger El Niño Events in the Future

It turns out that El Niño may be making a few appearances in the future. Scientists have found that the ocean is warming steadily and is setting the stage for stronger El Niño weather events in the future.

El Niños occur irregularly every two to seven years. They can often coincide with severe droughts in Queensland and New South Wales. In fact, current conditions show that a weak El Niño has brought warmer and drier conditions to Australia in late 2014.

In order to better understand future climate conditions, the researchers sampled corals from a remote island in Kiribati. This allowed them to build a 60-year record of ocean surface temperature and salinity.

"During an El Niño event warm water to the north of Australia move eastward, taking their rainfall with them," said Helen McGregor, one of the researchers, in a news release. "This changes the pattern of Australia's rainfall and droughts significantly."

In this case, the scientists focused on regional differences in sea temperatures that generate the circulating winds known as the Walker Circulation. This circulation drives the trade winds that bring moisture across the Pacific Ocean to the north of Australia. The researchers extracted coral core samples that told seasonal life stories of the coral.

"This coral quietly laid down an excellent record of the ocean conditions at that location," said McGregor. "It greatly complements direct measurements of the ocean temperatures made by humans throughout the 60 year period, filling in the inconsistencies and gaps."

In the end, the scientists found that the region may be heading toward stronger El Niño events as temperatures warm. This could have huge consequences for areas of Australia.

The findings are published in the journal Paleoceanography.