(So what time is it now? As of December 2011, it’s six minutes to midnight.) In 2007 the clock was updated to include non-nuclear dangers such as biological weapons and climate change. The farthest it has ever been from midnight was in 1991, when the end of the Cold War and the signing of the first Strategic Arms Reduction Treaty prompted the editors to move it from 10 minutes to 17 minutes ’til midnight in a single stroke. and the Soviet Union both tested hydrogen bombs in 1953, the clock was reset from three minutes to just two minutes before midnight, the closest to the zero hour that it has ever been set. Between 19, the minute hand was moved 19 times, closer to midnight when the Bulletin’s board of directors thought the danger of nuclear war was increasing farther from midnight when the danger was receding.ĭetails: When the U.S. How It Works: When the clock was created in June 1947, it was set at seven minutes to midnight. ![]() The clock has appeared on the cover of the Bulletin ever since. DEFCON 1 has never been used.īackground: By the summer of 1947, just two years after the atomic bombing of Hiroshima and Nagasaki, the directors of the University of Chicago’s Bulletin of Atomic Scientists had grown so concerned about the possibility of another nuclear war that they created a symbolic clock face called the “Doomsday Clock” to convey their estimation of how close the world was to “midnight”-nuclear Armageddon-at any point in time. During the 9/11 attacks the alert level never rose above DEFCON 3. That’s the only time since the creation of the system that any part of the military has been placed at DEFCON 2. ![]() Air Force’s Strategic Air Command was ordered to DEFCON 2. (Precise details of how the military increases its readiness when the DEFCON level is raised are kept secret.)ĭetails: Are you old enough to remember the Cuban Missile Crisis in 1962? Throughout much of the Cold War the military was kept at DEFCON 4, but during the Cuban Missile Crisis the alert level was raised to DEFCON 3, and the U.S. As perceived threats increase, the military’s readiness can be raised in stages all the way to DEFCON 1, when war is imminent. How It Works: DEFCON 5 is the lowest level of readiness in peacetime. military operations worldwide a simple measure of the nation’s current state of alert. The system was created in the late 1950s to give all U.S. In 2010 these elements were removed now it’s solely a wind scale.īackground: If you’re a fan of science fiction or war movies, you may already know that DEFCON is short for “Defense Readiness Condition” and is measured on a scale from 1 to 5. Both vary too much according to local factors such as the shape of the coastline and slope of the continental shelf where the hurricane makes landfall. How It Works: Hurricanes are classified into five categories according to wind speed: Category 1 (74–95 mph), Category 2 (96–110 mph), Category 3 (111–130 mph), Category 4 (131–155 mph), and Category 5 (156 mph and greater).ĭetails: The scale has proven ineffective at predicting flooding and the height of storm surges. Simpson and Saffir worked to incorporate potential damage from storm surges and flooding intro hurricane predictions their Saffir-Simpson Hurricane Scale made its debut in 1971. So he contacted Florida engineer Herbert Saffir, who had recently devised a five-category windstorm scale for the United Nations to predict how much damage would be caused to structures hit by winds of various strengths. ![]() Nonetheless, Simpson felt that a more effective way of communicating the size and likely impact of a hurricane was needed. Result: Fewer than 300 people were killed when it hit. New forecasting tools had enabled the Center to predict Camille’s intensity, and Simpson raised such an alarm that more than 81,000 people evacuated the affected areas. That are used to measure the bad things in life.īackground: Robert Simpson was the head of the National Hurricane Center in August 1969 when Hurricane Camille-one of the most powerful hurricanes ever to hit the United States-bore down on the Gulf Coast states. Here’s a look at some famous and not-so-famous indexes A few origin stories for some miserable things we’ve all heard of:
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