RIYADH: Sandstorms across the Middle East have delayed flights, closed schools and hospitalised thousands — a phenomenon experts say could worsen as climate change warps regional weather patterns.

Saudi Arabia on Tuesday became the latest country blanketed with dust that slowed traffic and made iconic towers in the capital difficult to see from more than a few hundred metres (yards) away.

Electronic signs along Riyadh’s highways warned drivers to reduce their speed because of the lower visibility, even as life largely went on as usual in the kingdom.

The national meteorology centre predicted that “surface dusty winds” originating in the east and bringing a thick grey haze would continue west towards the Muslim holy cities of Mecca and Medina.

Iraq sandstorm sends more than 1,000 to hospital

Other countries have been grappling with the problem for longer: Neighbouring Iraq has experienced eight sandstorms since mid-April, fuelled by soil degradation, intense droughts and low rainfall linked to climate change.

The country’s latest sandstorm on Monday enveloped the capital Baghdad in an orange glow, sent at least 4,000 people to hospital with breathing problems and led to the closure of airports, schools and public offices across the country. Iran announced that it, too, was closing government offices and schools Tuesday, citing “unhealthy weather” conditions and sandstorms.

Average airborne concentration of the finest and most hazardous particles (PM2.5) was at 163 microgrammes per cubic metre Tuesday in Tehran, according to a government website.

That is more than six times the World Health Organisation’s recommended maximum of 25 microgrammes per cubic metre.

In Kuwait, meanwhile, air traffic at the main airport was suspended for an hour and a half due to a dust storm Monday, and marine traffic in all three ports remained suspended as of Tuesday afternoon.