1 00:00:02,040 --> 00:00:07,680 Speaker 1: Welcome to brain Stuff from How Stuff Works. Hey, brain Stuff, 2 00:00:07,680 --> 00:00:11,320 Speaker 1: it's Christian Sager here. When hurricane season arrives each year 3 00:00:11,440 --> 00:00:15,960 Speaker 1: on June one, phrases such as storm surge, wind speed, 4 00:00:16,040 --> 00:00:19,560 Speaker 1: and eyewall suddenly become part of the summer lexicon in 5 00:00:19,560 --> 00:00:23,319 Speaker 1: the United States. But probably the most important words to 6 00:00:23,480 --> 00:00:27,040 Speaker 1: know about a hurricane are those that describe its power, 7 00:00:27,400 --> 00:00:30,360 Speaker 1: and those include whether it's a category one or a 8 00:00:30,400 --> 00:00:34,520 Speaker 1: category five. The variance between the strengths of these two 9 00:00:34,600 --> 00:00:38,440 Speaker 1: storms could mean the difference between life and death. Now, 10 00:00:38,479 --> 00:00:42,960 Speaker 1: meteorologists rank hurricanes from one to five based on the 11 00:00:43,040 --> 00:00:47,000 Speaker 1: Saffer Simpson scale. The scale is a yardstick that takes 12 00:00:47,000 --> 00:00:51,239 Speaker 1: into account a hurricane's wind speed, storm surge, and air pressure, 13 00:00:51,640 --> 00:00:54,440 Speaker 1: and the scale begins with a category one, the least 14 00:00:54,520 --> 00:00:57,600 Speaker 1: powerful and dangerous hurricane, and then it moves towards its 15 00:00:57,640 --> 00:01:02,440 Speaker 1: climax at Category five, the most catastrophic. As the storm 16 00:01:02,520 --> 00:01:07,080 Speaker 1: pushes across the ocean, it gathers speed and strength. Low 17 00:01:07,200 --> 00:01:10,720 Speaker 1: air pressure forces ocean water into a huge mound near 18 00:01:10,880 --> 00:01:14,800 Speaker 1: the eye, which could create a devastating storm surge. When 19 00:01:14,800 --> 00:01:17,760 Speaker 1: the wall of water reaches land. The more heat and 20 00:01:17,880 --> 00:01:22,640 Speaker 1: moisture hurricane consumes, the more powerful the storm becomes. That's 21 00:01:22,720 --> 00:01:26,160 Speaker 1: where the Saffer Simpson scale comes in. The scale was 22 00:01:26,200 --> 00:01:29,840 Speaker 1: created when Robert H. Simpson was director of the National 23 00:01:29,920 --> 00:01:34,320 Speaker 1: Hurricane Center in nineteen sixty nine, during the time Hurricane 24 00:01:34,400 --> 00:01:38,280 Speaker 1: Camille blew through the Caribbean and into the warm waters 25 00:01:38,319 --> 00:01:41,760 Speaker 1: of the Gulf of Mexico. Its winds were clocked at 26 00:01:41,760 --> 00:01:45,120 Speaker 1: a hundred and ninety miles per hour or three hundred 27 00:01:45,120 --> 00:01:49,560 Speaker 1: and six kilometers per hour as it struck Mississippi, and 28 00:01:49,600 --> 00:01:53,200 Speaker 1: the official death poll from wind storm surge in rain 29 00:01:53,400 --> 00:01:57,640 Speaker 1: was two hundred and fifty six people. In nineteen seventy one, 30 00:01:57,680 --> 00:02:01,520 Speaker 1: Herbert S. Saffer was working as an engineer in Florida 31 00:02:01,840 --> 00:02:05,120 Speaker 1: preparing a report for the United Nations on building codes 32 00:02:05,480 --> 00:02:09,640 Speaker 1: that could withstand the onslaught of high speed winds. He 33 00:02:09,840 --> 00:02:12,960 Speaker 1: eventually came up with a table that outlined the damage 34 00:02:13,000 --> 00:02:16,960 Speaker 1: to buildings wind can cause at various speeds. He worked 35 00:02:17,000 --> 00:02:20,440 Speaker 1: up five categories of hurricanes based on damage each one 36 00:02:20,480 --> 00:02:25,919 Speaker 1: could cause. In nineteen seventy two, Simpson took Saffers numbers 37 00:02:25,960 --> 00:02:31,240 Speaker 1: and correlated them with storm surge estimates and barometric pressure. 38 00:02:31,560 --> 00:02:35,679 Speaker 1: The result was the Saffer Simpson Scale by nineteen seventy five, 39 00:02:35,760 --> 00:02:40,160 Speaker 1: the Saffer Simpson scale was in widespread use local, state, 40 00:02:40,240 --> 00:02:43,359 Speaker 1: and federal officials, not to mention, the public at large 41 00:02:43,760 --> 00:02:47,200 Speaker 1: now had an easy to read and understand chart that 42 00:02:47,320 --> 00:02:51,840 Speaker 1: outlined a hurricanes impact. While the Saffer Simpson scale is 43 00:02:51,880 --> 00:02:55,240 Speaker 1: a good measuring tool, it doesn't really tell the full 44 00:02:55,320 --> 00:02:59,320 Speaker 1: story of a hurricanes impact. Hurricanes pack a lot of 45 00:02:59,400 --> 00:03:03,200 Speaker 1: connectic and energy, and as a byproduct, a hurricane's power 46 00:03:03,639 --> 00:03:08,480 Speaker 1: increases exponentially from one category to the next as wind 47 00:03:08,600 --> 00:03:13,320 Speaker 1: speed increases. A Category five hurricane, for example, is five 48 00:03:13,560 --> 00:03:17,520 Speaker 1: hundred times more powerful than a Category one. How does 49 00:03:17,560 --> 00:03:20,760 Speaker 1: this relate to property damage Compared to a Category one? 50 00:03:21,040 --> 00:03:25,160 Speaker 1: A Category to hurricane can generate seven times the amount 51 00:03:25,240 --> 00:03:29,080 Speaker 1: of damage, while a Category five storm can generate a 52 00:03:29,200 --> 00:03:34,720 Speaker 1: hundred and forty four times the amount of destruction. Today's 53 00:03:34,760 --> 00:03:39,520 Speaker 1: episode was written by John Paritano and produced by Dylan Fagan. 54 00:03:39,880 --> 00:03:43,200 Speaker 1: For more on this and other topics, please visit us 55 00:03:43,240 --> 00:03:51,880 Speaker 1: at how stuff works dot com. Today's episode was written 56 00:03:51,880 --> 00:03:55,440 Speaker 1: by Jescelyn Shields, produced by Dylan Fagan, and For more 57 00:03:55,520 --> 00:03:58,400 Speaker 1: on this and other topics, please visit us at how 58 00:03:58,440 --> 00:04:10,200 Speaker 1: stuff works dot com.