The phenomenon was discovered by Sir Gilbert Walker, who was researching the drought in India in the early 20th century and found an alternating variation in pressure between the eastern and western Pacific Ocean.
The phenomenon was discovered by Sir Gilbert Walker, who was researching the drought in India in the early 20th century and found an alternating variation in pressure between the eastern and western Pacific Ocean. He found that when pressure was high at Darwin, Australia (western Pacific) it was low at Tahiti (eastern Pacific), and vice-versa. However, it was only in the late 1960s that Norwegian meteorologist Jacob Bjerknes and others convincingly linked this with El Niño.