El-Nino: Comparing 1997 with 2015
The Oceans act like a battery for the added heat that has been trapped. Due to the thickened atmosphere we have made over the short 200ish years since the Industrial Revolution released the ancient sunlight stored as carbon.
Eventually this heat must be discharged back into the atmosphere.
As you can see. It is going to be an epic discharge.
We just passed a monumental point in warming. The 1C mark. We have raised the Earths temp by 1C. This is not a true reflection of the actual warming that has occurred. As sulfates from fossil fuels reflect back some of the incoming solar radiation. It estimated to be anywhere between 2C to 4C of warming that is masked through solar dimming. Think about it.