Pacific Ocean To determine the phase of ENSO, the most recent three-month sea surface temperature average for the area approximately to the southeast of Hawaii is computed, and if the region is more than above or below normal for that period, then an El Niño or La Niña is considered in progress. In the tropical western Pacific, the monsoon and the related wet season during the summer months contrast with dry winds in the winter which blow over the ocean from the Asian landmass. Worldwide, tropical cyclone activity peaks in late summer, when the difference between temperatures aloft and sea surface temperatures
Sea level rise level rise from satellite altimetry have been estimated to be per year for the period 1993–2017. Earlier satellite measurements were previously at odds with tide gauge measurements. A small calibration error for the Topex/Poseidon satellite discovered in 2015 was identified as the cause of this mismatch. It had caused a slight overestimation of the 1992–2005 sea levels, which masked the ongoing sea level rise acceleration. With satellites it is possible to capture regional variations in sea level rise well. In the 1993–2012 period for instance, sea level rose substantially in the western tropical Pacific. The sharp rise in this area