The answer is; Warm water moves to the east instead of to the west
Normally, when the waters in the Pacific warm up, the prevailing winds that blow from east to west drag the warm surface currents westwards and upwelling of cold currents occur at the west coast of South America. However, in El Nino, the Pacific ocean waters heat more than usual. The prevailing winds weaken and begin to blow predominantly towards the east. The warm currents are therefore dragged to the east and cause torrential rains in Western coast South Americas.
As epithelial makes the outer covering of all the organs and skin is also made of epithelial...so to be sure that it does not get depleted or destroyed due to friction and other external cause ...it should be highly generative !