Our directory of things of interest

University Directory

Dust up: storms and illness in North America

Dust up: storms and illness in North America BCFC; Tasoph
19 Jul
2017
A dramatic increase in dust storms across the western United States has occurred alongside an upsurge of valley fever. New research is exploring possible links between the two, and looking at the complex causes of both

The western United States, particularly states such as Arizona, California, New Mexico and Utah, has become drier and dustier over the past 40 years, and has experienced a 240 per cent increase in dust storms over that time as a result. Likewise, these same states have also seen an 800 per cent increase in cases of valley fever, a disease with flu-like symptoms which can occasionally be deadly. Researchers do not think this is a coincidence.

‘Valley fever is not contagious, it is caused by the coccidioides fungus, which lives in the soil,’ says Daniel Tong, atmospheric scientist at the National Oceanic and Atmospheric Administration (NOAA) and lead author of the study. He believes that the dust storms are whipping up the soil and transporting the fungus into populated areas. ‘More dust storms increase the chance of the fungus being inhaled by people,’ he says.

In Arizona, where the majority of all US valley fever cases are reported, dust was more strongly correlated with the disease than any other known factors. Nonetheless, this does not make it the sole cause, as the fungus itself grows in wet soil. This means the outbreaks are also related to factors such as rainfall, heat, wind and soil disturbance. Cautious not to get ahead of the findings, Tong states: ‘We found a positive correlation, but we would like to collect more data to help put the pieces together.’

dust graphicsThe largest number of US dust storms from 1988 to 2011 are concentrated in the southwest of the country, in the same states reporting the highest numbers of valley fever cases (Source: NOAA 2011)

It is crucial to understand this link, since many climate models indicate that we are in for more dust storms in the future. ‘The dust increase could be indicative of changes in large-scale climate systems,’ says Julian Wang, NOAA meteorologist. Specifically, the recent uptick in dust storms is linked to the warming sea surface temperatures of the North Pacific, which brings cooler and drier northerly winds into the southwestern United States. ‘The winds dry out the soil and kick up more dust storms,’ says Wang.

With drier weather expected to trigger stronger dust activity in the coming decades, all implications are being considered. Dust storms can degrade land, worsen asthma, and increase car accidents. ‘These events can transport the impacts of global climate variations onto local society and environments,’ says Wang.

Some of the most devastating dust storms in US history occurred during the Dust Bowl of the 1930s. For now, though, the team feels it is unlikely the storms could reach that scale. ‘The Dust Bowl was as much a human-caused disaster as a natural one,’ says Tom Gill, an environmental scientist at the University of Texas at El Paso. ‘Misguided land care practices, coupled with the Great Depression, magnified the effects of a major drought.’

Since then, modern soil conservation techniques and wind-reducing land practices have softened the impact of droughts that measure even stronger than those encountered in the 1930s. ‘That being said,’ continues Gill, ‘we know that the Southwest is subject to “megadroughts”, which last for decades, and is possibly overdue for one.’ Such a drought – which would be drier than the Dust Bowl – has not happened since European settlement and agricultural development of the region in the 1500s. ‘If – or when – a megadrought occurs, all bets are off,’ he warns.

This was published in the July 2017 edition of Geographical magazine.

Related items

Geographical Week

Get the best of Geographical delivered straight to your inbox every Friday.

Subscribe to Geographical!

EDUCATION PARTNERS

Aberystwyth University University of Greenwich The University of Winchester

TRAVEL PARTNERS

Ponant

Silversea

Travel the Unknown

DOSSIERS

Like longer reads? Try our in-depth dossiers that provide a comprehensive view of each topic

  • The Human Game – Tackling football’s ‘slave trade’
    Few would argue with football’s position as the world’s number one sport. But as Mark Rowe discovers, this global popularity is masking a sinister...
    Essential oil?
    Palm oil is omnipresent in global consumption. But in many circles it is considered the scourge of the natural world, for the deforestation and habita...
    National Clean Air Day
    For National Clean Air Day, Geographical brings together stories about air pollution and the kind of solutions needed to tackle it ...
    The green dragon awakens
    China has achieved remarkable economic success following the principle of developing first and cleaning up later. But now the country with the world's...
    Mexico City: boom town
    Twenty years ago, Mexico City was considered the ultimate urban disaster. But, recent political and economic reforms have transformed it into a hub of...

MORE DOSSIERS

NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...

Oceans

With the war against plastic gaining publicity and popularity, one…

Wildlife

India’s booming domestic dog population is attacking some of the…

Energy

Soaring sales of air conditioning units over the next thirty…

Climate

Well-meaning promises and actions don't always have the best outcomes.…

Geophoto

With the days at their longest and more light in…

Oceans

Tourism might be an economic pillar for many countries surrounding…

Wildlife

Brain sizes directly shown to correlate to survival rates among…

Wildlife

Celebrated author Professor Tim Birkhead provides a fascinating insight into…

Oceans

The world’s most biodiverse seagrass region – Indonesia’s Coral Triangle…

Oceans

Ocean conservation group urges world governments to step up action…

Climate

As climate conditions at the 100th meridian, the traditional United…

Climate

International shipping may be attempting to reduce its carbon footprint, but…

Geophoto

So much photographic theory is dedicated to image sharpness that…

Wildlife

Changing temperatures in East Africa are set to upset a delicate…

Climate

As the planet warms and tensions rise, Marco Magrini finds that…

Oceans

A deep-sea mission in the ocean around Bermuda confirms the…

Oceans

An oxygen-deprived ‘dead zone’ in the Arabian Sea is much…

Wildlife

Scientists working with new drone technology are hoping to reveal…

Oceans

A new virtual reality experience, ‘BBC Earth: Life in VR’,…

Nature

Faced with protecting a country more than 30 times the…