Earth is ‘twice as dusty’ now as it was a century ago

LONDON - A new study by U.S. scientists has revealed that the amount of dust in the Earth’s atmosphere has doubled over the last century.

And researchers believe that the increase could be a contributing factor to climate and ecology changes around the world.

To measure fluctuations in desert dust over the last century, lead scientist Natalie Mahowald and colleagues collected existing data from ice cores, lake sediment and coral, each of which contains information about past concentrations of desert dust in the region.

They then linked each sample with its likely source region and calculated the rate of dust deposition over time.

Applying components of a computer modeling system known as the Community Climate System Model, the researchers reconstructed the influence of desert dust on temperature, precipitation, ocean iron deposition and terrestrial carbon uptake over time.

They found that regional changes in temperature and precipitation caused a global reduction in terrestrial carbon uptake of six parts per million (ppm) over the 20th century.

The model also showed that dust deposited in oceans increased carbon uptake from the atmosphere by six percent, or four ppm, over the same time period.

While the majority of research related to aerosol impacts on climate is focused on anthropogenic aerosols - those directly emitted by humans through combustion - Mahowald said that the study highlights the important role of natural aerosols as well.

“Now we finally have some information on how the desert dust is fluctuating. This has a really big impact for the understanding of climate sensitivity,” the Daily Mail quoted her as telling Science Daily. (ANI)