El Nino does add heat to the atmosphere, and enough to raise the global mean temperature noticeably with a lag of about 3-6 months. In other words, the global mean temperature has a peak several months after the El Nino has its peak in SST. Because of this lag of a few months, and because El Nino usually lasts from about July through the following March, it means that the calendar year after the El Nino begins usually has a higher mean global temperature than the year that it begins. Applying this to the current El Nino, it means that 2016 may be even warmer than 2015, and we know that 2015 already is the warmest year on record so far. If the current El Nino decays quickly, 2016 probably won't be quite as warm as if it decays more slowly. We expect neutral ENSO conditions to begin around May or June. But in addition to the timing of when it returns to neutral, the extent of the above-average SST in the coming 2-3 months, when the El Nino will likely still be in the strong or moderate strength category, will also matter. The current westerly wind event will encourage the SST to remain above 2C above normal for a longer time than if this wind event were not occurring.