The causes and effects of El Nino
El Nino is a global phenomenon and was first noticed on the 1500s when Peruvian fishermen noticed changes in the abundance of fish and species. Many of the sea birds, which fed on the local anchovies suddenly disappeared. Therefore the name El Nino, meaning Christ’s child, originated because these winds and general changes occurred. In this essay, I will therefore assess the causes and consequences of such an issue.
In normal conditions, heat from the sun warms the equator more than it does at the Poles and at the same time, the winds or jet streams move the heat towards the cooler poles. The warm, moist air moves upwards, therefore pulling in the dry air from the ground. This in turn causes winds to move towards the evaporating air and a large convection loop is formed, thus transferring heat away from the equator. Under normal conditions, a convection cell is formed around the western Pacific area as well as Indonesia. The water that is blown westward is replaced by cold, more nutrient filled water, so when El Nino occurs, the convection cells move eastwards altering the pattern described. The diagram below shows the change from Walker Cell to the Southern Oscillation.
