El Niño and La Niña events are a natural part of the global climate system. They occur when the Pacific Ocean and the atmosphere above it change from their neutral (‘normal’) state for several seasons. El Niño events are associated with a warming of the central and eastern tropical Pacific, while La Niña events are the reverse, with a sustained cooling of these same areas. These changes in the Pacific Ocean and its overlying atmosphere occur in a cycle known as the El Niño–Southern Oscillation (ENSO).
El Niño is the “unusual warming in the Central and Eastern Equatorial Pacific.” Occurring in the Pacific basin every 2 to 9 years, it usually starts between December to February. When the temperature reaches 0.5˚C or higher for at least “5 consecutive overlapping 3-month seasons,” that is when El Niño is known to take place.
El Niño is a naturally occurring event, and there is nothing that can be done to stop its effects on the weather or on people around the world. However, because it can typically be noticed by meteorologists, people in the countries affected by it can take measures in order to curb some of the impact. Whether it be preparing for floods or droughts, people in the countries affected by El Niño must take the steps necessary to protect themselves. This can include stocking up on water in the case of a drought, or making sure their homes are able to handle flood waters. Because of the effect on many important crops in these countries, some steps for preparation might also include stocking up on these crops in preparation for the droughts or for damage caused by the flooding. It also affects the economic of a country, price of heating, foods, Political and social unrest, crash of fisheries, famine, plagues (hanta virus),,insect population explosion leading to disease and plagues, crops failure, etc.
In the Philippines, several factors determine when El Niño arrives. This includes the delayed start of the rainy season, early termination of the rainy season, and weak monsoon and tropical cyclone activity such as fewer tropical cyclones entering the Philippine Area of Responsibility (PAR). El Niño is that it severely affects the agricultural sector and both water, food, and power supply in the country. It can bring massive drought to the country which is why early warning is always reported to help concerned sectors to prepare about this event. Other effects of this event are reduced rainfall, stronger typhoons, and high risk of forest and grass fires.
On the other hand, La Niña is in the contrary. According to NASA, it is the “build up of cool waters in the equatorial Eastern Pacific.” Its effects are opposite to El Niño. Frequently, La Niña follows after El Niño. La Niña is a strengthening of the normal trade winds that typically occurs after El Niño. Basically, the normal, non-El Niño wind cycle is reinforced, pushing the warmest waters in the equatorial pacific further west than normal, and increasing the pulling up of cold water to the surface in the east. La Niña has an effect on global weather, as well, and this effect is typically the opposite of El Niño, causing droughts in the eastern equatorial Pacific and floods in the western equatorial pacific.
La Niña usually brings heavy rains that trigger floods and landslides, but it can also bring in benefits to the country such as the possibility to grow crops in mountainous areas and those areas that are unreachable by irrigation. These disastrous events of floods and landslides are brought by above normal rainfall, strong monsoon activity, and formation of more tropical cyclones.
Commonwealth of Australia 2017, Bureau of Meteorology
Rinkesh (2009) Conserve Energy Future
National Oceanic and Atmospheric Administration
Photo 1 by Vic Alhambra of Philippine Star, Photo 2 by Nonie Reyes of World Bank.
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