Morgan Larson and Livia Koehler 2017 Hurricane Season Morgan Larson and Livia Koehler

What is a Hurricane? A tropical cyclone with winds greater than 74 mph and that circulates counterclockwise about their centers in Northern hemisphere (clockwise in Southern hemisphere) Hurricane Irma

Conditions for Development & Stages Tropical Depression (winds < 39 mph) Tropical Storm (winds between 39-73 mph) Hurricane (winds > 74 mph) Development conditions Forms in warm ocean waters with temperatures over 80 degrees fahrenheit The water must be deep (200 feet or more) Located at least a few degrees north or south of the equator Can never cross the equator (no rotating air forces) Develops from pre-existing disturbances Tracking hurricanes using aerosols Tropical Storm= When storm is named Hurricane Harvey

Saffir-Simpson Hurricane Wind Scale Category 1 Winds: 74-95 mph Surge: 4-5 ft Damage: minimal Home damage: some Power outages: days Category 2 Winds: 96-110 mph Surge: 6-8 ft Damage: moderate Home damage: major Power outages: weeks Category 3 Winds: 111-129 mph Surge: 9-12 ft Damage: extensive Home damage: major Power outages: weeks Category 4 Winds: 130-156 mph Surge: 13-18 ft Damage: extreme Home damage: severe Power outages: months Category 5 Winds: 157 mph+ Surge: 19ft+ Damage: catastrophic Home damage: destroyed https://youtu.be/W3ghU4e2OKY

Major Hurricanes 2017 Harvey (August 17- September 1) Category 4 Winds reached 130 mph Hit Texas, Louisiana $90-160 billion in damages Record for most rainfall in US- 51.88 inches of rain over four days Irma (August 30- September 13) Category 5 Winds reached 185 mph- 37 hours Hit Florida, Georgia, South Carolina, and Caribbean islands $50-100 billion in damages Maria (September 16-30) Category 5 Winds reached 175 mph Hit Puerto Rico and Caribbean Islands $90-95 billion in damages Jose (September 5-22) Category 4 Winds reached 155 mph Hit Caribbean islands $2.84 billion in damages 17 storms, 10 hurricanes and 6 major hurricanes Lack of an El Nino system, wind, and unusually warm Atlantic temperatures

How Hurricanes Cause Damage High winds Saffir-Simpson Hurricane Wind Scale Storm surge Water rises above normal tide Extreme rainfall Flash flooding causes 59% of deaths Location Gulf and Caribbean Optimal locations for larger hurricanes Time of year June 1- November 30 Most dangerous: mid- October due to low wind Preparedness Evacuation Prevent property damage Climate Change

Hurricane Safety Hurricane warning During Storm Sustained winds of at least 73 mph are expected within 36 hours Hurricane watch Possibility of experiencing hurricane conditions within 48 hours If winds are not to reach hurricane status, tropical storm warnings/watches are issued instead Basic Preparedness Tips Know evacuation routes/have a plan Install permanent storm shutters or board windows with ⅝ inch plywood Trim trees surrounding home Fully fuel vehicles Stock up on supplies- water, first aid kit, flashlights, radios, etc. During Storm Stay indoors, away from windows Close interior doors Keep curtains and blinds closed Take refuge in small interior room, closet, or hallway on the lowest level Lie on floor under table/sturdy object Move to higher grounds Avoid contact with floodwater Leave mobile homes and reside in shelter

Climate Change Affecting Hurricanes? Weather disturbances Higher than average ocean temperatures Lack of wind shear Very humid air- hold moisture, so less rain falls during normal storms No El Nino/ El Nina Melting Antarctic ice caps by 1.6 meters per year Cause storms to be more intense and frequent 17 of 20 most destructive hurricanes (in US) have occured since 2000- worsening impact Harvey Caused greater rainfall Greater air temperatures allowed air to hold more moisture Rising sea levels made flooding more likely Stalled the hurricane, which caused more damage to Houston Irma Rising sea levels made flooding chances greater Average Florida temperature was 4/10th of a degree above normal Slows weather patterns- stalling

Economic & Societal Damages Harvey Forced 25% of oil and gas production to shut down, affecting 5% of nationwide output Affected 13 million people 88 people died Affected employment 203,000 homes damaged As people were recovering from Harvey, Irma began its destructive path 6.5 million Floridians were evacuated 102 people died Threatened Florida’s produce crops- No. 2 produce grower Could have done more damage- Floridians built better infrastructural buildings to better withstand the forces of a hurricane Maria 70,000 people evacuated in Puerto Rico 64 people died- official count; supposedly higher by 1,000- due to certain causes of death and miscommunication Flash-flooding causes 59% of deaths Record for having two Category 4+ hurricanes in the same year affect US

2017 Hurricane Season Overview 17 named storms 5th most active season (tied with 1936) since records began in 1851 All ten of the season's hurricanes occurred in a row Tied for greatest number of consecutive hurricanes ever observed in the Atlantic basin since records began in 1851 Costliest season on record, with a total of at least $283 billion in damages About $100 billion higher than the total of the previous record holder (2005 season) Historic hurricane season is June 1st- November 30th 2017 Season: April 19th (Tropical Storm Arlene) - November 9th (Tropical Storm Rina) 2017 Hurricane Season Overview June 1st- November 30th= Hurricane Season because these dates historically describe the period of year when most tropical cyclones form in the Atlantic basin Hurricane Maria

References https://www.nytimes.com/2017/09/08/climate/how-hurricane-irma-became-so-huge-and-destructive.html http://www.enchantedlearning.com/subjects/weather/hurricane/anatomy.shtml https://weather.com/en-CA/canada/news/news/2017-11-11-moments-hurricane-season-atlantic-irma-maria-harvey https://en.wikipedia.org/wiki/2017_Atlantic_hurricane_season https://www.tropicalweather.net/where-do-hurricanes-occur.html https://www.cnn.com/2013/05/30/us/hurricane-season-fast-facts/index.html https://www.cnn.com/2017/10/10/weather/hurricane-nate-maria-irma-harvey-impact-look-back-trnd/iindex.html https://www.almanac.com/content/how-survive-hurricane https://www.thebalance.com/hurricane-harvey-facts-damage-costs-4150087 https://www.thebalance.com/hurricane-irma-facts-timeline-damage-costs-4150395 https://www.thebalance.com/hurricane-damage-economic-costs-4150369 https://www.cnn.com/specials/hurricane-irma browardcollegeblog.com/hurricane-safety-tips-2/ abcnews.go.com/US/hurricane-harvey-projected-2nd-costliest-storm-us-history/story?id=49565583