You may have read or heard from social or mainstream print or electronic media that another El Niño is underway. El Niño has a significant impact on weather, insects, and human lives. Let’s first know what it is. El Niño is the warming of the ocean surface water in the central and eastern equatorial Pacific Ocean. It happens irregularly, usually between two years and a decade, and persists between two and nine months. There is no similarity between the two El Niños, which means the effects of this year’s El Niño are different from those of its predecessors.
El Niño year means get ready to embrace extreme weather. It generally triggers severe droughts in Australia, Indonesia, South Asia, and Southern Africa. The effects of El Niño in parts of the Americas and East Africa are heavy rains, floods, and warmer winters. Apart from causing extreme weather events, an El Niño year is characterized by pest infestations. This article will cover El Niño in detail, and its specific impact on pests population.
How El Niño Changes Global Weather
El Niño has a varied impact on global weather. Significant impacts of this climatic phenomenon are changes in rainfall patterns, higher temperatures in some regions, flooding in certain areas, and drought in others.
Changes in rainfall patterns are a hallmark of the El Niño period. When warm water develops along the equator in the eastern Pacific, it warms the atmosphere. A hot atmosphere forms moisture-rich air from the ocean, which rises and develops into rainstorms. These rainstorms result in as much as 12 millimeters more rainfall in the eastern Pacific, which extends into northwestern South America (Ecuador and Peru). Atmospheric disruption affects rainfall worldwide.
An El Niño year results in higher temperatures in some regions. When tropical trade winds become weaker, which is common during an El Niño period, massive pools of unusually warm water spread eastward across the Pacific. This alters the global weather, and some regions experience extreme heat when warm water releases heat into the atmosphere.
Severe flooding in certain areas during an El Niño period also results from unusally warn oceran surface in the central and eastern Pacific. A warm ocean surface disrupts the global atmospheric circulation, affecting where clouds form, where rain falls, and how the jet stream moves across different continents. Severe flooding occurs in areas where hot, moist air pushes upward, causing heavy rainfall and storms.
El Niño’s perhaps most devastating impact is drought in certain areas because it directly affects food security. Areas such as Southern Africa, the Sahel, Indonesia, South Asia, Australia, North-Eastern Brazil, Colombia, and Central America often face strong drought conditions that threaten the food security of millions of people. Again, the underlying reason for the drought is the unusual warming in the central and eastern Pacific Ocean. A warm ocean surface disrupts the global atmospheric circulation, displacing rain and bringing weather patterns such as monsoons away from these places, causing severe drought there.
Why Does El Niño Influence Pest Populations?
In addition to changing weather patterns, El Niño influences pest populations in agriculture, forestry, and public health. A warmer temperature, increased rainfall, and drought—all three conditions are responsible for increasing pest activity during an El Niño year.
Pest populations increase exponentially in the warmer temperatures of El Niño years. Warmer temperatures accelerate pest development and metabolism. As insects grow faster, it takes less time for them to grow, mate, and reproduce. The exponential growth of pest populations results from the shortening of their life cycles.
Increased rainfall in an El Niño period creates ideal breeding conditions for pests. Heavy rainfall creates pools of stagnant water, which is the best place for mosquitoes to breed and thrive. Flooding may force rodents to seek refuge inside homes, where they could be carriers of diseases. Since flies feed on garbage, their population will increase if trash and filth are not cleared after a storm. Other invaders such as centipedes, millipedes, earwigs, and roly-polies may swarm home with the rise of flood water.
Some pests are also influenced by droughts in an El Niño period. This period is often associated with harsh conditions, like a severe water crisis with elevated temperatures, which is favorable for those pests. Although stressful conditions are favorable for some pests, plants grown in such conditions tend to be smaller, less flavorful, and of low quality.
Which Pests Become More Active During El Niño?
Worldwide pest infestations are common during El Niño periods. Pests that become more active during this period are Mosquitoes, Rodents, Cockroaches, Termites, Flies, and other household pests.
Mosquitoes
Pooled, stagnant rainwater and heat create the ideal breeding conditions for mosquitoes in an El Niño period. Their population explodes, which increases the risk of mosquito-borne diseases such as dengue fever and malaria.
Rodents
Droughts, followed by heavy rainfall, produce dense, healthy vegetation in ample amounts, which is a stable food source for rats and mice. For food and shelter, rodents seek out homes and warehouses, where an endless food supply helps them proliferate exponentially.
Ants
Ants’ natural habitat dries due to the extreme heat of El Niño, forcing them to seek water and shelter inside homes.
Sucking and Agricultural pests
Insects such as aphids, whiteflies, thrips, and mites see a boom in population as warmer temperatures shorten their reproductive life cycles. In addition, heat-stressed crops become more prone to infestations.
Termites
Dry weather causes bushfires, destroying termites’ natural habitat, forcing them to seek refuge inside human-made infrastructure.
Can Climate Change Make Pest Outbreaks Worse?
A pest outbreak will become significantly worse due to the combined effects of El Niño and climate change. Global temperatures are steadily warming due to human-induced climate change. When it pairs up with El Niño-initiated warming, more disruptions in weather patterns in the form of excessive heat, rain, and droughts will occur. All of these uncontrolled natural events are catalysts for a pest outbreak.
El Niño is a centuries-old weather phenomenon causing extreme heat, heavy rain, and prolonged drought in several places in Asia, Africa, Australia, and the Americas. A major impact of El Niño is an outbreak of pest populations. This occurs due to the combined effect of human-induced climate change and naturally occurring El Niño conditions, such as extreme heat, rainfall, and droughts. While people have little control over weather-related disruptions such as excessive rain, extreme heat. and prolonged drought, reducing pest problems, is very much the opposite. Eliminating breeding sites, keeping home pest-proof, and maintaining clean Indoor, and outdoor spaces are human responsibilities.
