Warmth in the Antarctic stratosphere helped limit the size of the ozone hole in 2017 to the smallest observed since 1988, NOAA and NASA scientists say.
![This time-lapse photo shows the path of an ozonesonde as it rises into the atmosphere in the South Pole. Scientists release these balloon-borne sensors to measure the thickness of the ozone layer. Courtesy of Robert Schwarz/University of Minnesota (Image credit: South Pole, 2017 ) This time-lapse photo shows the path of an ozonesonde as it rises into the atmosphere in the South Pole. Scientists release these balloon-borne sensors to measure the thickness of the ozone layer. Courtesy of Robert Schwarz/University of Minnesota](/sites/default/files/styles/landscape_width_1275/public/legacy/image/2019/Jun/PHOTO-%20time%20lapse%20photo%20shows%20the%20path%20of%20an%20ozonesonde%20as%20it%20rises%20into%20the%20atmosphere%20in%20the%20South%20Pole%20-Photo%20by%20Robert%20Schwarz-1125x534-Landscape.jpg?h=e8cb3bb5&itok=pDJqct91)
This time-lapse photo shows the path of an ozonesonde as it rises into the atmosphere in the South Pole. Scientists release these balloon-borne sensors to measure the thickness of the ozone layer. Courtesy of Robert Schwarz/University of Minnesota (Image credit: South Pole, 2017 )