Tonnes of sand from deserts in China's interior blew into Beijing today, shrouding China's capital in a yellow-orange haze that authorities warned made the air quality "hazardous".
There were few people out on streets where pedestrians could taste the dust. Many of those who had ventured from their homes were wearing facemasks, and some left footprints in the yellow film that had settled on the city's streets.
Beijing's weather forecasting bureau gave the air quality a rare "5", or hazardous, rating and added that it was "not suitable for morning exercises". Parks and open spaces are usually packed from early in the day with enthusiasts doing martial arts,
ballroom dancing and other activities.
The sandstorms underline the environmental degradation investors identify as one of the long-term constraints on growth in China, and concern about its impact has made a less resource-intensive model of growth a priority for Beijing.
The government has spent millions of dollars on projects to rein in the spread of deserts, planting trees and trying to protect what plant cover remains in marginal areas.
But the battle is being fought against a backdrop of rising average temperatures and increasing pressure on water resources after three decades of booming growth.
The sandstorm hit Beijing around midnight, carrying huge amounts of dust and heading south east, the official Xinhua news agency said. In northern Changping district, the wind reached speeds of up to 100 km/h.
The swirling clouds of dust and sand had blanketed the interior provinces of Qinghai and Gansu, and western Xinjiang region, before sweeping over the capital, Xinhua said.