In 2024, sand and dust storms affected 330 million people across 150 countries taking a toll on health and economies, according to a new report by the World Meteorological Organization (WMO).

While the annual mean dust surface concentrations was slightly lower in 2024 when compared to 2023, there were big regional variations. In the most affected areas, the surface dust concentration in 2024 was higher than the long-term 1981-2010 average.

WMO estimates that between 2018–2022 around 3.8 billion people or nearly half the world’s population were exposed to dust levels exceeding World Health Organization’s (WHO) annual safety threshold for PM10.

“Sand and dust storms do not just mean dirty windows and hazy skies. They harm the health and quality of life of millions of people and cost many millions of dollars through disruption to air and ground transport, agriculture and solar energy production,” WMO Secretary-General Celeste Saulo said.

Overall, dust storms are worsened by poor land and water management, including urban sprawl and deforestation, which removes vital ground cover in arid or semi-arid areas, as well as drought. With climate change exerting pressure on all of these areas, WMO has underlined the need to improve monitoring, forecast and early warnings.

Increasing exposure trends

WMO estimates that every year, around 2,000 million tons of sand and dust enters the atmosphere –  equivalent to 307 Great Pyramids of Giza. Over 80% of this originates from the North African and Middle Eastern deserts, and can be transported across continents and oceans.

While much of this is a natural process, poor water and land management, drought and environmental degradation are increasingly to blame.

A new sand and dust storm indicator developed by WMO and the WHO shows that 3.8 billion people were exposed to dust levels exceeding WHO’s annual safety threshold for PM10 between 2018–2022. This represents a 31% increase from 2.9 billion people during 2003–2007.

This exposure varied widely from only a few days in relatively unaffected areas to more than 87% of days – equivalent to over 1,600 days in five years – in the most dust-prone regions of the world, including Africa’s Sahara, and Asia’s Gobi and Taklamakan Deserts.

Health impacts of sand and dust storms

Health impacts of sand and dust include respiratory and cardiovascular issues.

However, sand and dust particles from natural sources tend to be larger than the PM2.5 particles produced by combustion and industrial sources, which penetrate deeper into the lungs and into the cardiovascular system, causing impacts such as hypertension and cancer, as well as respiratory impacts.

Even so, natural dust sources may also carry with them dust from industrial sources such as urban construction and dust kicked up by road traffic, which may include benzene and diesel components as well as tire wear and tear.  In addition, there are significant threats to health when mineral dust, including a range of toxic compounds, is lifted from ploughed or bare fields. And this an occur in temperate or even humid climates, according to the WHO.

In addition, there are the socio-economic impacts. For instance, Iraq, Kuwait, Qatar, and the Arabian Peninsula were struck by an exceptional winter dust storm in December 2024. It led to widespread flight cancellations, school closures, and the postponement of public events.

“This Bulletin shows how health risks and economic costs are rising – and how investments in dust early warnings and mitigation and control would reap large returns,” Saulo said. “This is why sand and dust storms are one of the priorities of the Early Warnings for All initiative,” she added.

The WMO Sand and Dust Storm Warning Advisory and Assessment System coordinates international sand and dust research and has operational regional centres.

Geographical distribution of sand and dust storms

For 2024, the central African nation of Chad saw the highest annual average dust concentrations. Chad is home to the Bodélé Depression, a mountain-rimmed valley, which is one of the key dust emission sources of the Sahara desert.

In the southern hemisphere, annual average dust concentrations were highest in parts of central Australia and the west coast of South Africa.

In 2024, sand and dust concentrations were lower than what they normally are in many of the main source areas but and higher in areas where the dust blowed to. The transatlantic transport of African dust invaded the parts of Caribbean Sea region.

The regions that are most vulnerable to long-range transport of dust are: the northern tropical Atlantic Ocean between West Africa and the Caribbean; South America; the Mediterranean Sea; the Arabian Sea; the Bay of Bengal; central-eastern China.

Economic costs of sand and dust storms

While the global economic costs of sand and dust storms are not clear there are some country-level estimates. In the US alone, dust storms and related wind erosion cost an estimated $154 billion in 2017 – more than a fourfold increase over the 1995 estimate, according to one brand-new study, published in Nature in January.

The analysis included costs to households, crops, wind and solar energy production, as well as excesss mortality from fine dust exposure, health costs due to Valley fever, and transport. The true cost of dust was much higher, since reliable national-scale evaluations of many of dust’s other economic impacts (for example, on human morbidity, the hydrological cycle, aviation and rangeland agriculture) were not available, said the study’s authors, affiliated with the University of Texas and Virginia’s George Mason Universityy.

WMO, a UN agency, has been assessing sand and dust storms since 2007. The UN has declared the 2025-2034 as ‘Decade on Combating Sand and Dust Storms.’

Image Credits: WMO, The 2024 report of the Lancet Countdown on health and climate change: facing record-breaking threats from delayed action, Chris Ison/WHO, China Meteorological Administration (CMA) & WMO.