July 11, 2008—A swirling sandstorm born in the empty, arid lands of the Arabian Peninsula blows northeast across the Persian Gulf toward Iran on July 11, 2008, as seen by the Envisat satellite.

Such storms often form when light, warm air rises above sinking masses of colder, heavier air in a process called atmospheric convection.

During the region's summer months, sand and dust storms are regularly spurred by the shamal, a northwesterly wind that whips the region as air migrates toward a low-pressure center over Pakistan.

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