Less Dust Means Warmer Oceans

Less sand blowing over the Atlantic from the Sahara during the past 30 years is said to be the main cause of that ocean's warming trend ... not climate change.

Atmospheric researchers in Wisconsin say that decreases in the amount of dust in the atmosphere over the past 30 years have contributed to the warming of the North Atlantic Ocean far more than global warming.

Writing in the journal Science, University of Wisconsin-Madison’s Amato Evan says that more than two-thirds of the regional ocean warming can be attributed to changes in the amount of dust blowing off African deserts and variations in tropical volcanic activity during the period.

Evan and his colleagues at the Cooperative Institute for Meteorological Satellite Studies have previously shown that African dust and other airborne particles can suppress hurricane activity by reducing how much sunlight reaches the ocean, keeping the sea surface cool.

Dusty years signal mild hurricane seasons, while years with low dust activity have been linked to stronger and more frequent storms.

Evan points out that climate models have a difficult time factoring in volcanic activity since it is so unpredictable.

He says that new climate models should begin to include dust storms as a factor to accurately predict ocean warming.

Photo: NASA