As climate change intensifies due to global warming, weather events like El Niño and La Niña are causing extreme weather around the world. They have serious implications for agriculture, fisheries, economies, and more, and it’s important to understand and prepare for them.
Global warming is over, now the planet is boiling. This is not just rhetoric, but a description of the real crisis we face. The Earth’s temperature is already more than 1 degree Celsius above pre-industrial levels, and the effects are accelerating every year. Glaciers are melting at the poles, sea levels are rising, and extreme weather events are becoming more frequent around the world. These changes are not just affecting the natural environment; climate change is directly impacting human society, with reduced crop yields, ecosystem destruction, and water scarcity. As you can see, global warming is no longer a story of the future; it’s already a serious issue in our daily lives.
As the Earth’s temperature rises, extreme weather events increasingly threaten our planet. El Niño and La Niña are two of the phenomena that alter the Earth’s climate patterns the most. El Niño originally referred to unusually high water temperatures off the coast of Peru around Christmas. However, when scientists noticed that this phenomenon was accompanied by other anomalies, they concluded that El Niño was more than just a change in water temperature off the coast of Peru. El Niño has since been defined to include all of the extreme weather events that occur in conjunction with the changes in water temperature off the coast of Peru. In contrast, La Niña is the opposite of El Niño and refers to the anomalously low water temperatures off the coast of Peru and the associated extreme weather events. Here’s how El Niño and La Niña make a difference and how they work.
The Earth has an atmospheric circulation that is driven by solar radiation. This explains the prevailing wind patterns that form in different latitudinal ranges around the globe. The trade winds, westerlies, and polar vortices are part of these atmospheric circulations. In the South Pacific, there is the Southeast Trade Wind, which blows from east to west. These trade winds create the South Equatorial Current, a large flow of water from the coast of Peru (in the eastern Pacific Ocean) toward the coast of Indonesia (in the western Pacific Ocean). This South Equatorial Current moves ocean water into the Western Pacific. This lowers the sea level in the eastern Pacific, which requires a flow of seawater to make up for the lack of water. This results in upwelling, where cold deep ocean water rises to make up for the lowered eastern Pacific sea level. This results in cooler year-round water temperatures off the coast of Peru in the eastern Pacific. In addition, the southeast trade winds reach the western Pacific and rise upward from there. The rising air forms low pressure in the area and creates clouds. This causes clouds to form and rain in places like the Philippines, northeastern Australia, and Indonesia, where the updraft occurs.
El Niño occurs when the southeast trade winds weaken. When the Southeast Trade Winds weaken, the South Equatorial Current, which is generated by the Southeast Trade Winds, also weakens. This prevents the water in the eastern Pacific from moving westward as much, and sea levels in the eastern Pacific don’t drop enough. When sea levels in the eastern Pacific are not low enough, the flow of cold deep ocean water from below is weakened, and upwelling is also weakened. In this case, the temperature of the water off the coast of Peru rises because there is not enough cold water available. Warmer waters reduce the amount of dissolved oxygen and nutrient salts, which harms fish stocks. This phenomenon has serious implications not only in Peru, but globally. In addition to the Peruvian coast, the western Pacific is also affected. Due to the weakening of the southeast trade winds, the southeast trade winds don’t reach the western Pacific enough and rise. This creates an updraft, which shifts the location of clouds and rainfall further east than usual. This causes extreme droughts in the western Pacific, including northeastern Australia, where the updraft normally develops, but not during El Niño events. Other extreme weather events are known to occur during El Niño events, such as flooding in Central and South America and southern Mexico, and high temperatures in Alaska and western Canada.
La Niña is the opposite of El Niño and occurs when the southeast trade winds are stronger than normal. When the Southeast Trade Winds intensify, the South Equatorial Current becomes stronger. This results in a greater volume of seawater being transported from the eastern Pacific to the western Pacific, and sea levels in the eastern Pacific are lower than usual. In this case, upwelling intensifies to make up for the deficit. As a result, the water temperature off the coast of Peru in the eastern Pacific Ocean is cooler due to the cold water brought up by the upwelling. During La Niña events, stronger southeast trade winds create stronger upwelling in the western Pacific. This contributes to flooding in the Philippines and Indonesia, which are located in the western Pacific. Droughts in South America and severe cold in North America are also known to be caused by La Niña.
The effects of El Niño and La Niña are not just limited to climate change. They have far-reaching effects on economies, agriculture, fisheries, and ecosystems around the world. For example, extreme droughts caused by El Niño can significantly reduce crop yields, leading to higher food prices. This can lead to severe food crises, especially in developing countries. It can also affect marine ecosystems, leading to reduced fish catches, which can have an economic impact on communities that rely on fishing. Similarly, La Niña can cause extreme weather events in certain regions, leading to natural disasters such as floods and droughts, which can have serious ripple effects on the economy and society of the region.
In conclusion, El Niño and La Niña are not just weather events, but major climate patterns with global impacts. Understanding and preparing for them is becoming increasingly important in the era of climate change. It is up to all of us to continue researching and observing these events to better predict them and prepare accordingly. Without a better understanding and response to these phenomena, we are bound to experience not only natural disasters but also social and economic disruptions. Therefore, there is an urgent need for systematic research and policy development on climate change, including El Niño and La Niña.
