Michael Le Page
Five named tropical storms were present in the Atlantic on 14 September—only the second time this has happened since records began. The image here shows all five, plus tropical storm Karina in the Pacific. Most remained at sea, but Sally, which intensified into a category 2 hurricane, caused damage across the US Gulf Coast.
The 2020 hurricane season has been so active that all 21 names on the list for this year have been used.After storm Wilfred, which formed after this picture was taken, the US National Hurricane Center will use the name of Greek letters.
The number of tropical storms varies each year. High wind shear—the difference between wind speeds at the surface and higher up-can rip potential storms apart.
Global warming may not increase the number of hurricanes, but there is evidence that it makes them stronger and more damaging.