Regarding weather phenomena is concerned, we are more or less familiar with the concept of The child. We regularly hear news about how the recent weather has influenced. Nevertheless, The girl it may be less familiar to us, despite being closely related to it.
In fact, they are both the extremes, hot and cold, of something known as El Niño-Southern Oscillation (ENSO). However, now it is the name of La Niña that resonates in the headlines, for how it could influence the season of hurricanes from the Atlantic. A season that, in fact, is at a fever pitch, with the destructive scourge exerted by the Hurricane Ida over New Orleans.
But what exactly are the tantrums of these kids?
El Niño, La Niña and ocean temperatures
ENSO is defined as the climatic pattern that is formed with the oscillations of certain meteorological parameters in the equatorial Pacific.
Right at the extremes of these oscillations are El Niño and La Niña. That is, the first refers to the warm phase and, depending on they count from the National Office for Oceanic and Atmospheric Administration (NOAA) of the United States, corresponds to a heating annual sea surface temperatures along the west coast of tropical South America. As for La Niña, it is the cold phase. In fact, it originally referred to an annual cooling of ocean waters off the west coast of Peru and Ecuador.
It is important to note that these fluctuations are something normal, that it has nothing to do with the climate change. Yes that global warming is expected to influence it, and it is already beginning to be seen, but it is not entirely clear how this relationship will evolve. The consequences could be more drastic, but the existing models do not agree.
How does it affect the weather?
Leaving aside the influence of climate change and global warming, El Niño and La Niña, at different levels, influence the development of droughts, floods and hurricanes among other phenomena. Therefore, it is important to predict when these fluctuations will occur, as they help meteorologists to anticipate what could happen.
Both are the result of the interaction between the temperatures of the ocean surface and those of the atmosphere over the Pacific. This generates a kind of domino effect, in which some pieces fall on others, giving rise to very varied effects. To begin with, variations in ocean surface temperature affect the patterns of tropical rain and the atmospheric winds that are generated over the ocean. These, in turn, affect both temperatures and ocean currents. All this happens over the Pacific Ocean; but, in reality, it has been seen that it can affect weather patterns around the world.
In any case, it is important to emphasize that the meteorological phenomena that derive from El Niño and La Niña are not actually their unique consequences. We cannot say that a place suffers a drought or a hurricane due to La Niña, but rather that La Niña has affected, for example, the position of the air currents and the high and low pressure areas, resulting in those effects.
What can happen after Hurricane Ida
Both El Niño and La Niña are related to a multitude of Meteorological phenomena. For example, recently a team of scientists from the Columbia university Has published A study in which La Niña is related to the development of intense mega droughts in the last decade in the area of California and central Chile.
But, without a doubt, one of the most worrying effects is the one they have on hurricanes. To understand how this effect occurs, it is important to know what the shear. This is known as the difference between the speed or direction of the wind at two points on the Earth’s atmosphere. For a hurricane to occur, the winds must be very uniform, with little difference in speed at different heights, so the vertical shear must be low. And this is something that is highly influenced by El Niño and La Niña, as the shear rises and falls at different points. For example, it appears that El Niño contributes to more hurricanes in the eastern Pacific and fewer hurricanes in the Atlantic. Instead, La Niña encourages fewer hurricanes to form in the eastern Pacific and more hurricanes in the Atlantic.
Currently, the hurricane season in the Atlantic it is being especially powerful. So all eyes are on the possible staging of La Niña, which could reduce shear, postponing the end of this devastating stage until well into fall.
As explained recently in CNN Phil Klotzbach, a researcher at the Department of Atmospheric Sciences at the University of Colorado, a situation similar to that of 2020 could arise. Then, in the month of August it was predicted with a 60% probability that La Niña could erupt early in the fall, lengthening hurricane season. Only a month later, he appeared to accept the worst forecasts. This year, again, the United States Climate Prediction Center made a 60% prediction in the middle of the month. August is saying goodbye with the excessive rage of the Hurricane Ida and, if everything remains the same, there would still be a lot of damage to regret. That is why it is so important to know El Niño and La Niña. Because both, each in their own way, can turn the weather upside down in less than a rooster crows.