Infrequent triple dip La Ni a, which exacerbated the drought in the southwest of the United States, disrupted two busy hurricane seasons in the Atlantic, and brought record-breaking rainfall to Australia, has now passed.
March 9 saw the release of the National Weather Service’s Climate Prediction Center’s final warning for the ensuing cold phase of the ENSO cycle.
According to the institute, La Nia has finished, and ENSO-neutral conditions are anticipated to last until the Northern Hemisphere spring and early summer of 2023.
Why does this matter? Whether the waters in the central and eastern tropical Pacific Ocean are warmer than average (El Ni o), cooler than average (La Ni a), or neutral, i.e. average, that is indicated by the ENSO cycle. The Pacific Ocean’s temperature can affect weather all throughout the world, either warming or cooling.
El Ni o, for instance, is linked to colder, drier weather in the northern areas of the United States and heavier rain, and a higher danger of flooding in the Southeast and along the Gulf Coast, according to The New York Times. On the other hand, La Ni normally delivers wetter weather to the north and dryer, warmer weather to the south.
According to The New York Times and BBC News, the cycle generally rotates every two to five years, but this year was remarkable since this La Ni a, which started in September 2020, persisted for a third Northern hemisphere winter.
It is now ended, though, according to meteorologists, as Emily Becker of the University of Miami stated in NOAA’s ENSO blog because sea surface temperatures in the monitoring area were only 0.2 degrees Celsius below the long-term normal. Sea surface temperatures are 0.5 degrees Celsius lower than average during a La Ni period.
It is still unknown when conditions will change in El Nio, but forecasters estimate that they will stay neutral until the spring. Why is this important?
According to Becker, if we can predict an El Nio, we may predict an increased possibility of its effects on weather and climate. The tropical Pacific Ocean won’t play a role in the global climate play, though, if neutral conditions continue. There is no seasonal-scale effect from the Pacific to move the global air circulation and affect seasonal climate patterns because there is no El Nio or La Nia.
According to BBC News and The New York Times, the departing La Ni a, for instance, has been linked to the most and third-most active Atlantic hurricane seasons in 2020 and 2021, drought in East Africa and the U.S., and record-breaking rainfall followed by extreme flooding in eastern Australia in 2022.
According to Becker, there is a 60% possibility that by the fall the neutral pattern will change to El Ni o. If it occurs, this might exacerbate the climate issue and lead to even higher global temperatures.
Finally, the first triple-dip La Ni of the new millennium is drawing to a conclusion. Even though the last eight years were the warmest on record, La Nia’s cooling influence temporarily slowed the rise in global temperatures, according to a March 1 update from World Meteorological Organization Secretary-General Professor Petteri Taalass. A new increase in global temperatures is expected to result from the possibility that we are now entering an El Nio phase.
The warmest year on record was 2016, an El Nio year, and there is a 93 percent likelihood that it will be surpassed by 2026. Also, there is a 50% probability that the 1.5 degrees Celsius objective set forth in the Paris agreement would be temporarily exceeded by global temperatures.
Nonetheless, there are specific circumstances in which El Ni o could result in milder weather. According to Colorado State University meteorologist Philip Klotzbach, it often works against hurricanes because it increases wind shear.
The influence of the ENSO cycle is becoming more challenging to forecast as a result of the climate catastrophe.
According to Jan Null, an adjunct professor of meteorology at San Jose State University, the old La Nia and old El Nio playbooks don’t seem to be as accurate as they once were.
