How El Niño Marine influences ecosystems
How El Niño Marine influences ecosystems
el Niño is a widespread climate phenomenon that has large and profound effects on marine ecosystems. The changeable change in the climate influences the distribution and life cycle of many Mariner living beings and can sometimes cause major changes in their distribution and chances of survival. This article explains the mode of action by El Niño and how it influences Marine ecosystems.
The meteorology of El Niño
What is El Niño?
El Niño is a climate phenomenon that is characterized by an irregular change in temperature distribution in the Pacific Ocean. Usually warm water is driven from the tropics through the Passat winds west towards Asia, which enables the upward movement of cold, nutrient -rich water into the ocean. This process is referred to as a buoyancy.
During an el-Niño period, however, the Passat winds weaken or even change their direction and lead to the warm water in the ocean back towards America. This process suppresses the upward movement of the cold, nutrient -rich water and leads to a heating of the ocean surface in the eastern parts of the Pacific.
Periodicity of El Niño
Although El Niño is an irregular event, it usually occurs every two to seven years and, depending on the intensity and duration, can last for several months or more.
effects on marine ecosystems
The effects of El Niño on Marine ecosystems are far -reaching and affects all levels of the food network, from the smallest plankton organisms to the largest marine mugs.
Effects on primary production
The upward movement of cold, nutrient -rich water is crucial for primary production in the oceans because it supplies plankton and other microorganisms with the necessary nutrients. Due to the absence of this upward stratification during an EL Niño event, the nutrient supply on the sea surface is reduced, which results in a strong reduction in primary production. This has dramatic effects on the entire food network below this level.
Effects on fish populations
Fish are one of the strongest groups affected by El Niño, especially species that depend on the cold, nutrient -rich waters. The fishing industry often experiences significant losses in EL-Niño years, especially in anchovy and sardine fishing. But other fish species, including many important commercial species, can also be affected.
Effects on marine mammals
Marine mammals, such as sea lions, sea elephants and whales, also suffer greatly from the effects of El Niño. By reducing primary production and fish populations, the food base of these animals is severely restricted. This can lead to reduced reproductive rates, increased mortality and even mass extinction.
long -term effects and climate change
In the past few decades, El Niño has become more intense and more common. Some scientists suspect that this could be a result of global climate change. If this development stops, the effects on marine ecosystems could be even more serious and sustainable.
Changes in species compositions
As a result of El Niño, the species compositions in many sea systems can change significantly. There are reports of invasive species that penetrate new areas during EL Niño events and displace the local species.
shift in the distribution areas
In addition, El Niño can lead to the distribution areas of certain types, especially with regard to the water temperature and the nutrient content. This can have long -term effects on marine ecosystems and the human use of these resources.
el Niño is a powerful and far -reaching force in the global ecological network. While its immediate effects are mostly temporary, its long -term effects could be reinforced by climate change. It is therefore essential to further research the phenomenon and to understand its effects in order to better protect the future health of the oceans and its inhabitants.
sources:
Wang, C., Deser, C., Yu, J. Y., Dinezio, P., & Clement, A. (2017). El Niño and Southern Oscillation (ENSO): A Review. In Coral Reefs of the Eastern Tropical Pacific (pp. 85-106). Springer, Dordrecht.
Barber, R. T., & Chavez, F. P. (1983). Biological Consequences of El Niño. Science, 222 (4629), 1203-1210.
Brander, K. (2010). Impacts of Climate Change on Fisheries. Journal of Marine Systems, 79 (3-4), 389-402.