What is El Ni?o? Why does El Ni?o cause global warming?

El Ni?o is a phenomenon that occurs in the ocean. Its distinctive feature is the abnormal warming of seawater in the eastern and central equatorial Pacific.

Because tropical ocean areas receive a lot of solar radiation, the seawater temperature is correspondingly higher. In the tropical Pacific Ocean, due to the pull of the easterly equatorial trade winds, the equatorial ocean current flows from the eastern Pacific to the western Pacific, causing high-temperature water to continuously accumulate in the western Pacific, making it the sea with the highest seawater temperature in the world. Its seawater surface temperature reaches above 29°C. On the contrary However, the sea water temperature in the equatorial eastern Pacific is relatively low, generally 23 to 24°C. Due to the distribution characteristics of the sea temperature field, which is high in the west and low in the east, the tropical western Pacific shows rising airflow and low air pressure, while the tropical eastern Pacific shows sinking airflow. , the air pressure is higher.

Tropics

Under normal circumstances, the rising motion in the western Pacific is strong and precipitation is abundant. In the central and eastern equatorial Pacific, the atmosphere is sinking and precipitation is very little. When El Ni?o occurs, a large amount of warm water from the western equatorial Pacific flows to the eastern equatorial Pacific, causing the temperature of the water in the western equatorial Pacific to drop, weakening the upward movement of the atmosphere, and reducing precipitation, causing severe drought there. In the central and eastern equatorial Pacific, due to rising sea temperatures, rising motion has intensified, resulting in a significant increase in precipitation and heavy rains causing disasters.

El Ni?o is the result of unstable interactions between the ocean and the atmosphere. According to statistics, every strong El Ni?o phenomenon will lead to global climate anomalies, resulting in huge economic losses. 1997 was a strong El Ni?o year, and its strong influence lasted until the first half of 1998. El Ni?o was one of the most important influencing factors when we encountered the most severe floods in history.

Because the El Ni?o phenomenon brings huge disasters to the world, this phenomenon has become an important topic of research in the meteorological and oceanographic circles today.