A woman walks with her face covered during a sand storm in Dubai April 2, 2015. (Photo by Ahmed Jadallah/Reuters)

Children are engulfed in dust as a convoy of escorted taxis carrying Muslims, fleeing sectarian violence, arrives at a temporary internally displaced person camp at the airport in Bangui, Central African Republic January 30, 2014. (Photo by Siegfried Modola/Reuters)

A man walks during a sand storm in Dubai April 2, 2015. (Photo by Ahmed Jadallah/Reuters)

Sand blows across the coastal highway near Brega in eastern Libya, April 1, 2011. (Photo by Finbarr O'Reilly/Reuters)

A massive sand storm cloud is close to enveloping a military camp as it rolls over Al Asad, Iraq, April 27, 2005. (Photo by Cpl. Alicia M. Garcia, U.S. Marine Corps/Reuters/U.S. Department of Defense)

A traffic light shows red as a dust storm blankets the Sydney Harbour Bridge at sunrise September 23, 2009. (Photo by Tim Wimborne/Reuters)

A dust storm blankets Sydney's iconic Opera House at sunrise September 23, 2009. (Photo by Tim Wimborne/Reuters)

Private First Class Brandon Voris, 19, of Lebanon, Ohio, from the First Battalion Eighth Marines Alpha Company stands in the middle of his camp as a sandstorm hits his remote outpost near Kunjak in southern Afghanistan's Helmand province, October 28, 2010. (Photo by Finbarr O'Reilly/Reuters)

A woman covers her face against a sandstorm on a street in Tianjin, China March 20, 2010. (Photo by Vincent Du/Reuters)

Dust envelops art installations during the Burning Man 2013 arts and music festival in the Black Rock Desert of Nevada, September 1, 2013. (Photo by Jim Urquhart/Reuters)

A man walks past a coal plant amidst a dust storm in Lingwu, Ningxia Hui Autonomous Region, China March 29, 2011. (Photo by Reuters/Stringer)

Men ride a motorcycle through a heavy dust storm along a road in Greater Noida on the outskirts of New Delhi, India October 23, 2012. (Photo by Vivek Prakash/Reuters)

Two people look at the scene of a multiple vehicle collisions along Interstate-10 during a dust storm near Casa Grande, Arizona, December 22, 2009. (Photo by Joshua Lott/Reuters)

A Kurdish Syrian refugee covers her face as she waits for transport during a sand storm on the Turkish-Syrian border near Suruc in Sanliurfa province, Turkey September 24, 2014. (Photo by Murad Sezer/Reuters)

Tiananmen Square is seen amid a sandstorm in Beijing, China March 20, 2010. (Photo by Grace Liang/Reuters)

A gold mine worker takes shelter from a sandstorm in Al-Ibedia locality at River Nile State, Sudan July 30, 2013. (Photo by Mohamed Nureldin Abdallah/Reuters)

A man rides a bicycle during a dust storm in Kashgar, Xinjiang Uighur Autonomous Region, China April 16, 2013. (Photo by Reuters/Stringer)

An internally displaced man, who fled a military offensive in the Swat valley region, sits outside his family tent during a dust storm at the UNHCR Jalozai camp, about 140 km (87 miles) northwest of Islamabad, Pakistan July 2, 2009. (Photo by Akhtar Soomro/Reuters)

Hindu devotees endure a dust storm while heading towards the Shri Hinglaj Mata Temple in Balochistan province, Pakistan April 24, 2011. (Photo by Akhtar Soomro/Reuters)