Washington: New evidence has emerged which indicates that dust storms in the arctic, possibly caused by receding glaciers, may be making similar deposits in northern Europe and North America, thus affecting the health of the people in the countries there.
Joseph Prospero from the University of Miami and colleagues found the evidence.
“Our recent work in Iceland has shown that most of the dust events there are associated with dust emitted from glacial outwash deposits, which may be carried into the northern latitudes and into Europe by synoptic weather events,” said Prospero.
Satellite data have shown large dust plumes in the arctic, but persistent cloud cover has made finding the origins difficult.
The glaciers have been retreating in Iceland for decades, and the trend is expected to continue with the changing climate.
Prospero predicts that dust activity from the newly exposed glacial deposits will most likely increase in the future in Iceland and possibly from other glacial terrains in the Arctic.
Prospero’s lifelong work has been to measure the effects of airborne dust.
Since 1965, he and his colleagues have been measuring dust particles in Barbados, West Indies, thus creating the longest dust measurement data set in science.
They found that dust transport increased greatly during the late 1960s and early 1970s at the same time as a severe drought in Northern Africa.
“The first 30 years of the dust record showed a strong relationship between dust transport across the ocean to rainfall amounts in the Sahel and Soudan regions of Africa,” said Prospero.
“It’s important to note that the level of dust transport is not necessarily related directly to rainfall but possibly to other climate factors associated with the variability of rainfall,” he added.
Some of the most intense periods dust transport are associated with strong El Nino events, which may affect such factors as wind speeds and variability as well as rainfall—the same factors that affect dust mobilization and transport.
However, since the late 1990s, the pattern of drought and dust transport has been disrupted—dust transport rates were actually greater than what Prospero``s earlier model would indicate.
“We still have worked to do to understand the fundamental processes and relationship between climate, rainfall, and dust transport,” said Prospero.
“Predicting the long-term effects of climate and dust transport is exacerbated by the fact that many of the climate prediction models for lower latitude Africa are not consistent,” he added.