Does SST increase during El Niño?
With an increase in the zonal SST gradient (as observed for the 1980–2019) extreme El Niño will occur more frequently, which in turn, will significantly enhance precipitation than that observed for the historical simulation (up to 20%) in East Asia and North America.
How does El Niño affect SST?
During El Niño, positive SST anomalies in the equatorial eastern Pacific and the associated westerly wind anomalies cause a meridional poleward Sverdrup transport of equatorial warm water, resulting in a basin-wide raised thermocline.
What are the social impacts of El Niño?
El Niño has affected food security and agricultural production, with cascading effects on livelihoods, health, water, sanitation, education and other sectors. This is due to flooding, disease outbreaks and malnutrition, disruption of health and education services, and overall increased mortality.
What happens to the warm pool during an El Niño?
During an El Niño water temperatures in the Pacific Ocean may rise on average 3 – 5 degrees above average. This pool of warmer water expands westward toward North and South America.
What is a SST anomaly?
Sea surface temperature is the temperature of the top millimeter of the ocean’s surface. An anomaly is a departure from average conditions. At irregular intervals (roughly every 3-6 years), the sea surface temperatures in the Pacific Ocean along the equator become warmer or cooler than normal.
Are we El Nino or La Niña 2021?
Here’s what that means for winter weather in the U.S. This Climate.gov graphic shows how La Niña generally affects weather conditions in the United States. Forecasters say there’s a nearly 90% chance that La Niña conditions will be in place from December 2021 to February 2022.
Which is the smallest of the Nino SST indices?
Nino SST Indices (Nino 1+2, 3, 3.4, 4; ONI and TNI) Niño 1+2 (0-10S, 90W-80W): The Niño 1+2 region is the smallest and eastern-most of the Niño SST regions, and corresponds with the region of coastal South America where El Niño was first recognized by the local populations. This index tends to have the largest variance of the Niño SST indices.
Why are SST anomalies so small in La Nina?
Herein after the model is referred to as the “CZ model.” It is known that in the CZ model, the small SST anomalies during La Niña are due to the parameterization of subsurface temperature, which prevents excessive cooling beyond a certain threshold of thermocline depth.
Which is more nonlinear La Nina or El Nino?
The nonlinearity appears not only in the atmosphere but also in the sea surface temperature (SST) anomalies. The El Niño SST anomalies tend to be greater than those during La Niña.
How are El Nino and La Nina sea surface temperature anomalies investigated?
[1] The asymmetric nature of El Niño and La Niña sea surface temperature (SST) anomalies is investigated by the use of National Centers for Environmental Prediction reanalysis data and various ocean and atmosphere models.