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Chile's Most Prominent Hazards

Chile is highly susceptible to many natural hazards, but the two biggest threats are earthquakes and extreme weather, specifically drought. Why they happen & why I'd address them as a priority Earthquakes ThinkHazard says Chile's earthquake hazard is classified as high, meaning there is more than a 20% chance of a potentially-damaging earthquake taking place in the country in the next 50 years. The potential for hazard is particularly high due to its 3,000 km long subduction zone along the coast and because of the relatively high subduction velocity (6-7 cm per year) of the Nazca plate upon which it sits on. To sum it up:1/4 of all global seismic energy released in the past century occurred there . Chile has had 13 major earthquakes in the last 30 years, and boasts the largest earthquake ever recorded (a M 9.5 in Santiago, 1960 - fyi), AND many of these quakes trigger either landslides, tsunamis, and/or volcanic activity. That being said, I think earthquakes would b...

Chile's Coastal Hazards

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Tsunamis The risk of Chilean coasts being affected by tsunamis is classified as high, according to ThinkHazard. The website says this means that Chile has a 20% chance of a potentially-damaging tsunami occuring in the next 50 years. An example of a tsunami that wreaked havoc over Chile is the earthquake and tsunami Maule. Maule On February 27th, 2010 a huge earthquake occurred off the coast of Maule in central Chile, just 70 miles from Chile's second largest city, Concepcion. A post about this earthquake/tsunami on the SMS Tsunami Warning website states, "It occurred on the subduction zone plate boundary at the Peru - Chile Trench where the oceanic Nazca Plate subducts beneath the continental South American Plate", resulting in a quake of 8.8 magnitude.  The map here signifies the epicenter of the quake as the red dot with the star, while the yellow dots represent areas that felt aftershocks of the quake until March 25th, 2010 (holy cow). The post also...

Extreme Weather

This week I will be focusing on Extreme Heat! Extreme heat is classified as a hazard of "medium" danger in Chile, according to ThinkHazard. The website includes, "there is more than a 25% chance that at least one period of prolonged exposure to extreme heat, resulting in heat stress, will occur in the next five years". Much of the extreme heat hazard is caused by the increase of global temperatures due to global warming and the country's placement on the equator, however according to the most recent assessment report from the Intergovernmental Panel on Climate Change in 2013, northern Chile's "temperature increase in the next fifty years will be slightly higher than the worldwide average". Example Just a couple years ago in 2016, a heat wave in Chile's capital of Santiago broke the record heat set 100 years prior. For the last century, the record had been 98.96 degrees Fahrenheit (set back in 1915), and had been broken by a 99 degree Fahr...

Mass Wasting in Chile

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Hazards Chile's middle and southern regions are areas of high susceptibility to mass wasting, while the northern regions are classified with low to very low susceptibility, as you can see on this map from ThinkHazard. The reason for the concentration of landslide hazards in the central and southern regions is explained by Sergio Sepulveda, a student at the University of Chile. Sepulveda says, "In Chile, debris flows are usually triggered by heavy rainfall, although the amounts of precipitation required to initiate the flows are very variable according to the climatic regime".  Northern areas of Chile are classified as having an extremely dry climate (< 2 in of rain/yr), as it boasts the driest desert in the world, the Atacama. The central regions of Chile are classified as having a Mediterranean-like climate (12-40 in/yr), and the southern regions rainy-temperate (40-80 in/yr, sometimes reaching up to 157 inches in the southern coastal islands). Of course, ...

Volcanic Activity in Chile

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Turns out Chile has a ton of volcanoes.  In fact, there's about 2,000 of them dotted around the Andes, but the majority of them are dormant or extinct. Chile has the second largest volcano chain in the world, after Indonesia. According to an article on ChileCulture.org, "About 500 volcanoes are potentially active, 36 are currently active and 44 have erupted at least once since 1820". In addition, there have been 15 eruptions in the last 20 years. Other interesting facts The last eruption in Chile was of Calbuco Volcano in Puerto Varas on April 22, 2015 Here's a time lapse video ;-) ~ video ~ According to the Global Volcanism Program, the Chaiten volcano in the southern region of Chile erupted in 2009 - its most recent eruption prior to it was around the year 7420 BC +/- 72 years (what the heck?!) Most of the large volcanoes are stratovolcanoes There's also plenty of geysers, hot springs, and fumaroles  How Chile Warns its People I actually w...

Seismicity in Chile

Because Chile is so prone to seismic activity, their earthquake preparedness and preventative measures are some of the best in the world. Warning Systems Following the 8.8 earthquake of 2010 that claimed the lives of more than 500 people, Chile "implemented a new system that alerted residents by telephone, computers and television in real time". The system, compromised of a network of digital broadband seismic and ground motion stations, Global Navigation Satellite System (GNSS) stations, and GPS stations, allows Chile to capture accurate information for damage assessment and warnings. Chile has also recently experimented with a newer system the rest of the world may soon adopt, called G-FAST. The Seismological Society of America describes G-FAST as using "ground motion data measured by GNSS to estimate the magnitude and epicenter for large earthquakes". The implementation of this system could allow even more time for earthquake warning and evacuation in the fu...

Chile's Plate Boundaries

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Chile is located essentially at the convergence of the South American, Nazca, and Antarctic plates. The South American and Nazca plates converge at about 88 mm per year (one of the fastest rates in the world) making Chile an area highly vulnerable to earthquakes, tsunamis, volcanism, and landslides. Chile's earthquakes in particular tend to be very powerful, so powerful in fact that it boasts the location of the largest earthquake of the last 200 years - the 9.5 earthquake of 1960. The strength of these humongous earthquakes often causes large earthquakes and tsunamis to occur elsewhere. For example, the 1960 earthquake caused a tsunami that caused loss of life not only in Chile, but Japan, Hawaii, and the Philippines as well. Chile has encountered 13 major earthquakes in the last 30 years. Citations: Image “The Chilean Earthquake: The Plate Tectonics.”  Physics Today , American Institute of Physics, 1 Mar. 2010, physicstoday.scitation.org/do/10.1063/PT.5.024122/full/. ...