What is El Niño, and why does it happen?
El Niño refers to the fluctuations in temperature between the ocean and atmosphere in the east-central Equatorial Pacific, resulting in a series of climate anomalies every few years. It is the warm part of the whole ENSO (El Niño-Southern Oscillation) cycle, with La Niña as its cold counterpart. The video above explains the process.
Why should you care about El Niño?
El Niño is part of the global climate system, thus influences not only regional, but also worldwide climate and weather. Due to the climate anomalies that come with its arrival, there are higher chances of extreme climate and weather occurrences, including floods, droughts, forest fires, and landslides during an El Niño season. There are also global environment and economics repercussions, alongside effects upon the marine biology of the Pacific Ocean, during El Niño.
What are the climate anomalies related to El Niño?
The major anomaly connected to El Niño is the higher than normal ocean surface water temperature around equatorial Pacific Ocean. This warmer water disrupts the normal pattern of tropical precipitation and atmospheric circulation. On average, El Niño lasts between 7 to 9 months (called an El Niño Condition); if and when El Niño extends it presence longer, it is called an El Niño “episode”.
Weather during an El Niño is characterized by an increase in the frequency of precipitation across the east-central and eastern Pacific Ocean during winter, sometimes resulting in major flooding. Conversely, in the west-central Pacific Rim, the summer season can be abnormally drier and hotter, bringing along severe drought. This most recent El Niño has resulted in the worst drought in recent two years in Brazil, while the 2015 India heat wave has killed thousands of people because of abnormally hot and dry temperatures without relief.
What are other impacts related to El Niño?
Climate anomalies and temperature fluctuation can greatly affect agriculture, with food shortages and famines a strong possibility because of extreme drought conditions in the western tropical Pacific area. An upcoming consequence of this year’s El Niño will be higher food prices across the world.
Another interesting economic effect of El Niño is the lower price of gas during the winter. In the East Coast of the United States, gas is primarily a heating fuel. However, El Niño brings warm air from the Pacific Ocean, which brings with it a warmer winter season, therefore reducing the demand, increasing availability of heating gas, and keeping prices low.
El Niño can also affect marine species, mainly in Pacific Ocean, due to the sea water temperature change. For example, we’re seeing the appearance of venomous sea snakes washing upon Southern California shores, a species normally found in tropical parts of the Pacific and Indian Oceans. The warmer oceanic temperatures are also believed to be associated with the increasing risk of certain disease such as malaria and cholera.
Graphic: Jan Null/Golden Gate Weather Services
A brief history of El Niño
The chart above shows the Oceanic Nino Index (ONI) since 1950; the ONI displays deviations of the sea surface temperature from the average. The further the graph point is charted from the 0 axis, the worse the El Niño was. The previous worst El Niño on record happened in 1997-1998, resulting in more than 20,000 fatalities attributed to El Niño, and at an economic loss of $340,000,000. Violent weather, disastrous floods in southern America, severe drought in Central America, and four sequential hurricanes hitting Mexico made the 1997-1998 El Niño particularly damaging.
Graphic: National Oceanic and Atmospheric Administration(NOAA)
El Niño in 2016?
Even though El Niños vary in duration and intensity, the meteorological phenomena exhibits some standard patterns that help scientists make educated predictions. Meteorologists predict we are going to have a strong El Niño for 2016, and possibly one even worse than the previously noted 1997-1998 season using prediction models comparing this year with that historic El Niño.
2015 has been the hottest year on record. Alhough El Niño is not the solel reason for global warming, the previous two hottest years on record – 2010 and 2005 – both featured El Niños. On the other hand, the west tropical Pacific region is gaining more moisture than usual this winter and spring. Yet, California’s predicted precipitation peak has yet to occur, meaning Angelenos should expect more wet weather to arrive in the coming weeks and months.
Can El Niño save the severe drought in California?
The increasing precipitation is going bring some relief to drought-dried land for sure, but it is not likely to end the drought. El Niño might bring Southern California more rainfall, but most of our state’s water supply system and reservoirs are located in the north, requiring not only rain, but a stable and sizable snow pack. However, there is now much talk about improving infrastructure to capture as much rainfall as possible for improved water resource management, so there might be a positive outcome in the longterm related to El Niño’s appearance in the wake of an epic drought.
For some tips about how to collect rain water, please take a look at our previous post, 4 Ways to Collect and Store Rain.
Some misconception about El Niño.
- El Niño causes global warming: It might contribute partially to higher global temperatures, but not entirely.
- El Niño is directly responsible for extreme weather events.
- El Niño will only increase the potential and frequency of weather events.
- El Niño will bring disastrous floods in California: With the increased frequency of rainfall, it is possible we will see floods in California, but not absolutely fatal ones. According to state records, some of the most devastating floods in California history happened outside of El Niño years.
- El Niño is only a climate concern: El Niño effects are beyond the climate. The weather abnormalities associated with El Niño can impact the global economy, may increase fetal disease, or even result in species extinction due to the long last extreme climate.
Are there any benefits related to El Niño?
- El Niño reduces the frequency of Atlantic hurricanes.
- Winter is warmer in certain regions, and therefore less energy is needed for heating.
- There is more rainfall for the southwest region of the United States.
- Ski resorts on the West Coast are opening sooner than usual.
- There might be chance to swim or kayak on the street.
How can we prepare for El Niño?
First, be calm. El Niño is not going to bring the end of the world. Check out this website put together by the City of Los Angeles informing citizens how to prepare for El Niño. The most important resource on the site as far as I am concerned is to sign up for update alerts for floods, mud slides, or other emergency conditions. It might be also advisable to insure personal properties and vehicles ahead of possible damage related to El Niño.
Overall, we need to be aware of the strong presence of the coming El Niño, paying attention to scientific predictions, and help each as a community to overcome any problems that El Niño brings with it.