Why are the Americas under the threat of natural disasters?
How are hurricanes, earthquakes, wildfires, and tsunamis related?
As devastating as Hurricane Harvey was for Texas, as bad as Hurricane Irma has gotten, these two hurricanes are not the only threats the Americas are currently facing. The earthquake in Mexico, the wildfires in most of the U.S’s west coast, the tsunami threat in 8 Latin American countries, and Hurricanes Katia and José, fast approaching Mexican land, are the natural disasters the continent currently faces. But why are they all happening now? Is this normal?
As reported in my latest piece on Hurricane Irma, scientists have reason to believe that although the storm itself was not caused by global warming, there is a high chance that its intensity was worsened by the effects of climate change due to greenhouse gases. However, this is not the only explanation scientists have explored with regards to all the natural disasters the continent faces.
One of the major factors that affect the intensity of hurricanes and their frequency, as well as the causes of tsunamis and wildfires, is atmospheric temperature and atmospheric conditions in general. While global warming does affect atmospheric conditions, it is not the only aspect that causes alterations. For instance, as chief of Meteorology at NBC Miami John Morales has explained, this year we do not have El Niño, which tends to augment cyclones in the Pacific but reduce them in the Atlantic. This may be one of the reasons why hurricanes José and Katia have formed at the same time as Irma, unrelated to, or at least not directly caused by, global warming.
Tectonic plate movements may also cause the water of the ocean to warm up, which is a key factor in the strength of hurricanes and tropical storms. The warmer the water, the stronger the storm, because warmer water means higher humidity. Humidity is what “nourishes” a hurricane, as meteorologist Morales also explained. Global warming also causes ocean water to warm up because it absorbs most of the heat caused by the greenhouse effect, so it is also a cause of stronger and more frequent hurricanes and storms.
The devastating earthquake in Mexico, with 35 casualties reported so far, was caused by tectonic plate movement. One of the consequences of the earthquake was the tsunami warning issued for eight Latin American countries: Guatemala, El Salvador, Costa Rica, Honduras, Panamá, Ecuador and Mexico. The countries were warned by the Pacific Tsunami Warning Center to expect massive and dangerous ocean waves. According to the educational website Windows to the Universe, tectonic plates move because the core of the Earth is malleable, at extremely high temperatures. If the core shifts, the movement travels all the way to the surface, and that is how earthquakes happen. The seismic waves caused by this movement also cause tsunamis. Hence, the tsunami warning in Latin America is directly related to the earthquake in Mexico, but these events are not necessarily caused by global warming. Professor Bill McGuire of the University College of London has published a book and has studied the link between earthquakes and global warming, concluding that these phenomena might be correlated. The science behind the theory is quite complex, but basically McGuire has found that man-made climate change has caused ice sheets that remained on the planet from the Ice Age to melt. As a consequence, tectonic plates move.
The other disaster that is threatening the continent are the wildfires. California is regularly a victim of wildfires, but usually these stay in Southern California. This year, as shown in the live map of the government of California’s fire website, the fires have spread all over the U.S’s west coast, going as far north as Oregon and as far South as the border with Mexico. As reported by journals like National Geographic, most wildfires are caused by people who light campfires and not putting them out properly, or don’t dispose of flammable waste properly. But why are this year’s fires worse? Are people getting more careless? Is global warming also causing fires to light up more easily? Statistics show that the amount of fires has been rising for years: it is not a recent issue. “The effects of global warming on temperature, precipitation levels, and soil moisture are turning many of our forests IGNORE INTO kindling during wildfire season”, according to the Union of Concerned Scientists.
The data shows that the common denominator in all, or at least most, of these natural disasters is global warming. In some the influence is more obvious than in others. However, what we do know is scientists have shown that climate change affects the environment and our planet in ways that we have not faced or even imagined yet.
Latin American Post | Laura Rocha Rueda
