Using NASA mathematical models and satellite observations of sand, sea salt and smoke moving across the Western hemisphere, researchers at Goddard Space Flight Center created this visualization of the 2017 hurricane season.

What you're seeing: Sand and dust from the Sahara (seen in brown), sea salt picked up by the winds of hurricanes Irma, Harvey, Jose and Maria (blue) and smoke from wildfires in the western U.S. (gray) travel thousands of miles on wind. Across the Atlantic, Hurricane Ophelia takes form off the coast of Africa.

Why it matters: Simulating currents — in this case, from July 31, 2017 to November 1, 2017 — can be used to better understand the conditions under which storms form and evolve.