4 days ago
WMO report reveals urgent need for action against rising dust storms in Southern Africa
A new World Meteorological Organization report warns of the exacting toll that sand and dust storms are having on global health and economies. The report pinpoints South Africa's West Coast as a dust hotspot, with some of the highest concentrations in the southern hemisphere.
Have you ever noticed a hazy sky, felt grit in the air, or seen a wall of dust approaching while on the West Coast? These are all signs of airborne dust, a natural phenomenon that is increasingly being influenced by human activities and climate change.
The World Meteorological Organization (WMO) recently released its Airborne Dust Bulletin, providing a global overview of airborne dust in 2024.
This report, along with other recent findings, offers insights into how dust storms affect our health, economies and environment, with significant implications for countries like South Africa.
Key findings from the 2015 WMO Airborne Dust Bulletin, its ninth, are that sand and dust storms now affect about 330 million people in 150 countries; there is increasing economic disruption and health impacts from this; and poor land and water management, as well as drought, play a major role in this.
Global sand and dust storm hotspots in 2024
Dust is a natural part of our planet's system, but the WMO has emphasised in its latest bulletin that human factors are playing an increasingly significant role in its prevalence. Poor land and water management, ongoing droughts and general environmental degradation are making the problem worse.
As WMO secretary-general Celeste Saulo puts it: '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.'
The report highlights several hotspots where dust concentrations were particularly high in 2024.
In the southern hemisphere, the West Coast of South Africa and central Australia saw their highest dust concentrations, ranging from 150 to 300 micrograms per cubic metre. This directly brings the global issue of airborne dust home to South Africa.
This is because vast and remote deserts in Namibia and the Northern Cape are a major natural source of dust, and strong winds pick up this dust and blow it over the West Coast. This leads to extremely high concentrations of dust in the air for areas in the Western and Northern Cape, which, the WMO has confirmed, have levels among the highest recorded.
As Leonie Joubert previously reported in Daily Maverick, the Northern Cape may be headed for an irreversible dust bowl following yearslong drought and decades of intensive mining and grazing.
Dust storms are rare in South Africa, but they do occur over certain parts of the country.
Then, in the northern hemisphere, the bulletin noted that the central African nation of Chad, home to the Bodélé Depression (a major dust source), experienced peak annual mean surface dust concentrations of about 800 to 1,100 micrograms per cubic metre of air.
Major dust storm events in 2024 were observed across various regions in the bulletin:
Canary Islands (December 2024): A strong 'Harmattan' wind surge from northwestern Africa carried dust from the Western Sahara Desert to Spain's Canary Islands, significantly impacting areas where most people live;
East Asia (June 2024): Northern China, including Beijing, experienced rare summer dust storms. This was linked to poor vegetation growth in Mongolia due to high temperatures and drought, showing how extreme weather in a changing climate can drive such events; and
West Asia (December 2024): Iraq, Kuwait, Qatar and the Arabian Peninsula were hit by an exceptional winter dust storm, causing widespread disruptions, including flight cancellations, school closures and postponed public events.
The increase in dust in some regions is linked to a mix of natural and human-caused factors. These include more intense droughts, stronger winds and changes in how land is used. Things such as overgrazing, cutting down too many trees, poor land management, rapid growth of cities, new buildings and the drying up of important natural areas like marshes all make the soil less stable and more likely to turn into dust.
The health implications of sand and dust storms are a major focus of the WMO report. A new indicator, developed jointly by the WMO and the World Health Organization (WHO), revealed a worrying trend: between 2018 and 2022, about 3.8 billion people – nearly half of the world's population – were exposed to dust levels exceeding the WHO's safety threshold.
Local challenges and national efforts
The WMO report's mention of the West Coast of South Africa as a region with high dust concentrations in the southern hemisphere shows that dust and sand storms are a local reality.
South Africa is no stranger to dust storms; they are rare, but they do occur, and they can wreak havoc on agricultural land, damage property, worsen air quality, disrupt road and air travel and cause significant health problems, even leading to loss of life.
A large dust storm swept across parts of the country in October 2014, which mainly affected Free State areas and De Aar in the Northern Cape, and another major dust storm affected parts of the country in January 2016.
In 2019, people 'watched skies turn red' in Alexander Bay in the Northern Cape on 25 September as fierce winds carried huge plumes of sand and dust westward towards the Atlantic Ocean. This was visible from satellite imagery, according to the Nasa Earth Observatory, while photographs from people in Alexander Bay showed dark, hazy skies and streets that were barely visible.
In fact, in a letter dated 10 October 2017, Transnet Port Terminals (TPT) addressed property owners in Vredenburg, Saldanha and Langebaan regarding a project to clean and paint properties affected by iron ore dust. The project's progress has been slow, partly due to Level 3 water restrictions preventing the use of drinking water for high-pressure cleaning.
This points to damage to property from iron or dust, and how drought affected addressing the situation locally.
Now, the report found that these storms are linked to both natural factors like precipitation and wind, and human factors. But there's also growing concern that the changing climate could be increasing the frequency, intensity and spread of these major dust events.
The impact on public health
From a public health perspective, understanding the implications of dust storms and sharing preventative measures is crucial. The South African Medical Research Council, in partnership with the Department of Health and the Department of Forestry, Fisheries and the Environment, has developed basic health protection steps for the public to take during dust storms.
A study titled 'Exploring Meteorological Conditions and Human Health Impacts during Two Dust Storm Events in Northern Cape Province, South Africa: Findings and Lessons Learnt' (Nkosi et al., 2022) delved into the health effects of two specific dust storms in South Africa.
This research, conducted at a large public hospital in Kimberley, on the border of the Northern Cape and Free State, examined hospital admissions for respiratory and cardiovascular diseases, eye irritation and motor vehicle accidents during and after dust storm events in October 2014 and January 2016.
While initial statistical analyses didn't show significant changes in admissions directly at the time of the dust storms, a more advanced technique called wavelet transform analysis revealed some delayed effects.
They identified a cluster of hospital admissions for respiratory and cardiovascular diseases, eye irritation (and motor vehicle accidents) that were recorded between three and 40 days after the two dust storm events.
Specifically, they found a small but statistically significant increase in hospital admissions for eye irritation up to 30 days after a dust storm.
This aligns with international findings, since eye irritation is one of the most common health outcomes associated with dust storms. The study also suggested that the admissions might be linked to a combination of temperature and aerosol variations at the start of the dust storms.
The researchers acknowledged that other factors, such as high background levels of dust from natural sources and human activities like biomass burning, could also contribute to hospital admissions, making it challenging to isolate the exact impact of dust storms alone.
The health consequences of dust exposure can range from immediate effects like skin and eye irritation, decreased lung function and increased cardiovascular issues, to more long-term concerns such as adverse pregnancy outcomes.
This research also stated that children, newborns, the elderly, pregnant women and individuals with chronic heart and lung conditions were particularly vulnerable.
Unfortunately, South Africa currently has limited long-term national data on dust storm patterns and their precise health impacts, so the researchers noted that there was a need for more research to inform evidence-based policies.
Towards a dust-resilient future
Recognising the increasing threat of dust storms, the United Nations General Assembly officially declared 2025-2034 as the United Nations Decade on Combating Sand and Dust Storms on 10 July 2024. This global initiative aims to coordinate efforts to prevent, halt and lessen the negative impacts of these storms through shared early warning systems, scientific guidance and sustainable land management.
South Africa is also taking steps to address this challenge. The Draft National Dust Control Amendment Regulations, 2025, published by the Department of Forestry, Fisheries and the Environment in May, aim to improve dust control measures within the country. These regulations, which repeal and update the 2013 version, focus on:
Identifying specific activities that generate dust;
Updating the standard methods for collecting and measuring dustfall; and
Improving the requirements for developing, implementing and reporting on dust management plans.
Under these new regulations, certain individuals or entities, such as those involved in mining, reclamation or activities that generate dust and cause a nuisance, will be required to develop and submit dust management plans for approval.
Failure to comply can result in significant penalties, including fines of up to R5-million (about $270,000) or imprisonment for up to five years for a first offence, with even higher penalties for repeat offences.
WMO told Daily Maverick that the message from this latest report is to encourage governments to strengthen the capacity of national meteorological services to improve forecasts and early warnings. They noted that the South African Weather Service already has a very good track record in this respect. DM
