Close, but not entirely accurate. During an El Nino, the Pacific currents weaken because equatorial trade winds in the area weaken. This is caused by air pressure differentials or lack there of. Basically less wind because less pressure differences between east and west Pacific. So you basically have an enormous dead pool of water receiving solar radiation everyday. Surface warms. That heat is transferred into the atmosphere mainly via evaporation. Water vapor from evaporation is the primary green house gas component. So we get a short term atmospheric warming. The El Nino eventually ends when trade winds start blowing again. This occurs when the pressure differential between east and west Pacific increases again. The El Nino heat that gets transferred into the atmosphere is actually being transferred into space. After of coursing warming the atmosphere in the short term. During La Nina the trade winds are so strong that Pacific currents cause deep cold water to upwell in the Eastern Pacific. Basically us apes to date have been clueless about the physical processes involved. You will realize this in about 6 months.
nice explanation