When people think about seasonal weather events, they typically think of events such as hurricanes or wildfires. However, there are other seasonal weather events that have a great affect on the climate of the Americas. El Niño and La Niña are two weather patterns that have a great affect one the climate of the Americas.
El Niño and La Niña are part of what is known as the El Niño-Southern Oscillation Cycle, or the ENSO cycle. The ENSO cycle refers to changes in the temperature of the ocean and atmosphere in the Pacific Ocean, specifically between the International Dateline and 120 degrees West. La Niña is the term used for the cooling of water and El Niño refers to the warming of water. Episodes of El Niño and La Niña typically occur every 2-7 years, and on average last 9-12 months, but they can last longer. El Niño usually occurs more often than La Niña.
El Niño typically leads to warmer than average temperatures across western and central America and less precipitation in the Ohio Valley and the Pacific Northwest. The Northeast will experience slightly warmer temperatures, and the southern United States will have a cooler than normal winter. The southern US will also have more precipitation this winter, providing some relief to drought-stricken California, although not enough to end the drought.
This year El Niño is supposed to be especially strong, and in some locations people are already feeling the impact. The impact of El Niño is widefelt across the global. Lack of rain in Vietnam has farmers worried about having enough water to irrigate their crops, while Sumatra, Borneo, and New Guinea are struggling to put out wildfires due to the lack of precipitation. To make matters even worse, smoke from the wildfires has caused air quality in Singapore to decrease. The increased rainfall could are harm Florida’s orange crop, which is already suffering from a citrus-greening disease (the disease grow stronger in wet environments). The warming waters will cold-water species of fish to swim northward or deeper into the ocean to escape the warmer water. As the fish move away, bird populations must migrate as well in order to remain fed. Another effect of El Niño is there will be less severe storms in both the Atlantic and Pacific Oceans. While this is in many ways a good thing, unfortunately many inland tropical areas require the precipitation provided by El Niño. Nevertheless, El Niño is sure to have an impact on the weather this year.