How do the numbers of active volcanoes in the Pacific Ocean and Atlantic Ocean compare?

There are about 1,500 potentially active volcanoes worldwide, aside from the continuous belts of volcanoes on the ocean floor at spreading centers like the Mid-Atlantic Ridge. About 500 of those 1,500 volcanoes have erupted in historical time. Many of those are located along the Pacific Rim in what is known as the "Ring of Fire." In the United States, volcanoes in the Cascade Range and Alaska (Aleutian volcanic chain) are part of the Ring, while Hawaiian volcanoes form over a 'hot spot' near the center of the Ring.