Need for a rethink of ‘the critical role’ of atmospheric dust in Earth’s climate

Saharan dust storm [image credit: BBC]

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It seems ‘classical dust cycle models have over-estimated the amount of dust emission.’ This in turn affects the results from climate models, which ‘have only been providing a fraction of the story’. This ‘has significant implications’ for reconstructions of past climate.
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You may think of dust as an annoyance to be vacuumed and disposed of, but actually, on a grander scale, it is far more important than most people realize, says Phys.org.

Globally, dust plays a critical role in regulating our climate, radiation balance, nutrient cycles, soil formation, air quality and even human health.

But our understanding of it has been hampered by limitations in current mathematical models. These models, built on methods developed decades ago, struggle to accurately simulate the properties and quantities of dust.

The latest research by my colleagues and I sheds light on these limitations and suggests a more nuanced picture of dust. Our findings reveal that dust emissions are not constant but shift seasonally and between hemispheres, across deserts and shrublands.

This challenges the long-held notion that north Africa and the Middle East are the dominant sources of global dust.

Using two types of satellite data, our research suggests that dust emissions during dust storms are rare and localized, much like lightning strikes, and occur in constantly shifting locations.
. . .
[The article concludes…]
These new findings are crucial for large scale models because the properties of dust are different depending on where they come from. Not only that, but dust may change as it is transported within a hemisphere to different destinations where it settles on land, in our oceans and on icecaps.

Our new understanding of dust distribution, quantity and seasonal shifts has significant implications. It will require revisions to historical reconstructions that explain past climate changes.

Our findings will also influence future climate projections and how the dust cycle interacts with the carbon, energy and water cycles of Earth’s systems.

Full article here.
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Image: Saharan dust storm [credit: BBC]