New Delhi, May 12 -- Ocean temperatures in April were the highest since a record spell of warmth in 2024, climate models showed, as the world's waters heat up rapidly with a strong El Nino event approaching. The average global sea surface temperature (SST) this April was 21degC, the second-highest ever recorded for the month, just below the record 21.04degC in April 2024, when oceans were gripped by unprecedented heat, according to data released last week by the Copernicus Climate Change Service (C3S). At the same time, a broad stretch of waters from the central equatorial Pacific to the western coast of the US and Mexico recorded their warmest-ever April, the dataset showed. Rapid ocean warming is a key feature of El Nino -- a climate pattern marked by above-average sea surface temperatures in the central and eastern tropical Pacific Ocean. El Nino events typically develop every two to seven years and last around nine to 12 months. Seasonal models have predicted that an El Nino pattern could develop between May and July this year and may become one of the strongest on record. In India, El Nino is usually associated with harsher summers and weaker monsoons. C3S data also showed that global air temperatures last month were the third-highest ever in April - 14.89degC, or 1.43degC above pre-industrial levels. April 2024 was the warmest April on record at 15.03degC. There were, however, significant regional contrasts across the Northern Hemisphere, although less pronounced than earlier this year. Much of southwestern Europe experienced warmer-than-average conditions, with Spain recording its warmest April on record, while eastern Europe saw colder-than-average conditions. In the Arctic, sea ice extent was the second-lowest ever recorded for April and remained close to record lows for this time of year, continuing a trend seen since the beginning of the year. Large parts of the North Indian Ocean, including the Arabian Sea and Bay of Bengal, have started recording warmer-than-average temperatures, according to C3S data. It also showed that surface temperatures over Central Asia and Southeast Asia are extremely high once again....