Scaffold Writing Worksheet: Earth Science – Unit 7: Meteorology Unit and/or Grade 8 Science

Billion Dollar Betsy Betsy was the first Atlantic tropical cyclone to cause at least a billion dollars in damages. Hurricane Betsy, which is reported as one of the deadliest and costliest storms in United States history, began as a tropical disturbance in late August of 1965. And within a few days it had intensified into a hurricane, 200 miles north-northeast of San Juan, Puerto Rico. Over the next couple of days, the hurricane looped 440 kilometers (275 miles) north of Puerto Rico weakening to a tropical storm. Turning west, on September 1, the storm regained hurricane status and drifted 560 kilometers (350 miles) east of Daytona Beach, Florida. At this point, the hurricane appeared to be heading toward the Carolinas. However, on September 4 it made a second loop and shifted southwest toward Florida. The hurricane passed over the Bahamas and stalled over Nassau. On September 7, Betsy moved toward extreme southern Florida and on September 8, the hurricane made its first landfall in Key Largo, Florida as a Category 3 hurricane.

What type of damage do hurricanes produce? ______

What was the path of Hurricane Betsy (up to Sept. 8)? ______

It is not unusual for the wind speeds to change in a hurricane as they move. Sometimes they even drop below 74 mph so as now to be classified as a tropical storm (above 39 mph but below 74 mph). In order for a hurricane to develop they require energy. They obtain this energy from the heat energy at the ocean (sea) surface. Therefore, hurricanes arise from the warm waters (80 degree or warmer) of the tropical oceans in the summer and early fall. The ocean waters must be warm enough at the surface to put enough heat and moisture into the overlying atmosphere to provide the energy for the hurricane. As winds blow across the warm ocean surface water evaporates into water vapor that rises and cools and condenses to form clouds. As the warm air and moisture rise, they create a low pressure on the water surface, which is immediately replaced by cooler air. This process continues producing thunderstorms and rain. In addition, winds that move in a circular manner due to the Earth’s rotation (Coriolis Effect) cause the entire weather system to spiral around a central point (eye). As the system moves over warmer waters, the clouds expand even more and the winds begin to speed up. The eye is surrounded by a towering vertical movement of thunderstorms called the eye wall. The eye is the calm center of the hurricane while the eye wall has extremely violent 74+ mph spiraling winds.

What is the difference between a tropical storm and a hurricane? ______

Why do hurricanes weaken when they travel over land? ______

Describe (in more detail) how a hurricane is produced: ______As the storm moved out of Florida and into the Gulf of Mexico, it shifted once again—this time to the north-northwest- and re-intensified into a Category 4 storm with winds up to 250 km/h (155 mph). On the evening of September 9, the hurricane made its second landfall as a Category 3 hurricane at Grand Isle, Louisiana, just west of the mouth of the Mississippi River. Winds gusted above 160 km/h (100mph) across much of southeast Louisiana, with hurricane-force winds recorded as far inland as Lafayette, LA (~270 kilometers [170 miles] away), and points north. The storm continued through central Louisiana, essentially traveling upriver and causing the Mississippi River at New Orleans to rise by 3 m (10 feet). The river crested in Baton Rouge at 4.6 meters (15.5 feet). By 10 September, the system was over Arkansas with diminishing winds. Shortly after, the system headed toward the Ohio Valley as a tropical storm.

Flooding caused by Hurricane Betsy was widespread across the Gulf coast, with storm surge noted as far east as Mobile, Alabama. Grand Isle, Louisiana saw a 4.8 meter (15.7 foot) surge wash over its northern coast - practically all buildings in Grand Isle were either severely damaged or destroyed. Due to the surge, hundreds of ships, tugs, and barges were sunk or driven aground from New Orleans to Baton Rouge. Eleven shipwrecks blocked 30 miles of the Mississippi River. One barge, which contained enough chlorine to kill tens of thousands of people if released, sank in 18.3 meters (60 feet) of water near the University of Louisiana campus. After weeks of government efforts, the barge was safely located and refloated without incident.

What would have happened if Hurricane Betsy made its landfall as a Category 4 hurricane and not a Category 3 hurricane at Grand Isle, Louisiana? ______

What is storm surge? ______

Why is storm surge dangerous? ______The hurricane brought a 3 meter (10 foot) storm surge to New Orleans, producing the city’s worst flooding in decades. The surge was driven into Lake Pontchartrain, just north of New Orleans, and the Mississippi River Gulf Outlet (MRGO), a deep-water shipping channel to the east and south. Levees for the MRGO and on both sides of the Industrial Canal failed, causing dramatic flooding very similar to that which occurred during Hurricane Katrina in 2005. Also similar to Katrina, this flooding overloaded the city’s pumping system, which failed when 90% of the city’s electric power was knocked out. Typical Levee Describe a levee and its function: ______

Why did the levees fail in New Orleans? ______In all, 164,000 New Orleans homes were flooded after the second landfall. Residents fled to their rooftops to escape the rising waters. After an unprecedented relief effort, it was ten days or more before the water level in New Orleans receded and residents could return to their homes. It took even longer to restore flooded houses to a livable condition. Seventy-six total deaths were a direct result of Hurricane Betsy. A total of $1.42 billion ($9.8 billion 2010 USD) in damages were estimated, with most of those damages occurring in Louisiana.

Hurricane Betsy was the first hurricane to accrue damages over $1 billion, and was thus nicknamed “Billion Dollar Betsy.” Due to the tremendous amount of damage caused, “Betsy” it was retired from the hurricane list and replaced with the name “Blanche”. The U.S. Army Corps of Engineers' Hurricane Protection Program came into existence as a result of Hurricane Betsy. The Corps built new levees for New Orleans that were designed specifically to resist a fast- moving Category 3 hurricane like Betsy. The resulting levee improvements failed when Hurricane Katrina, a large, slow- moving, intense hurricane made landfall near New Orleans on August 29, 2005.

Why do you think the new levees built by the U.S. Army Corps of Engineers failed when Hurricane Katrina hit New Orleans in 2005? ______

Diagram 3: HURRICANE BETSY OVER THE ATLANTIC OCEAN AT NOON SEVERAL DAYS IN 1965 Directions: Using Diagram 3 complete questions A, B, and C.

A. State two actions that the United States Weather Bureau most likely advised coastal residents to take to prepare for Hurricane Betsy. 1. 2.

B. In which compass direction did Hurricane Betsy move between September 1 and September 4?

C. Determine the latitude and longitude position of the center of Hurricane Betsy at noon for the dates indicated below in the table. DATE (noon) ° N ° W Aug 29 Aug 30 Aug 31 Sept 1 Sept 2 Sept 3 Sept 4 Sept 5

Diagram 4: A Hurricane in the Gulf of Mexico: Distance per Day Directions: Using Diagram 4 determine how far did the hurricane move each day from September 13th to September 20th? You will need a metric ruler to measure the distance between the given dates. And then must use the scale to estimate the actual distance in kilometers (km).

Date Range Distance in mm Approximate Distance (km) on map Using Scale (kilometers) Sept 13-14 Sept 14-15 Sept 15-16 Sept 16-17 Sept 17-18 Sept 18-19 Sept 19-20 Total Distance

Forecasting Hurricanes Even with sophisticated technologies, hurricanes remain difficult to predict. Our understanding of why hurricanes can suddenly intensify is still not completely understood by scientists. The forecasting of hurricanes consists of two components: (1) tracking – where the hurricane is going and its (2) intensity – how strong it is at a given time. Currently, hurricane forecasts are issued to 5 days and very shortly will be up to a week. Our tracking forecasts have greatly improved due to the increased number of satellites with more sophisticated weather-monitoring devices. In addition, computer systems and models to forecast hurricane direction have also improved exponentially. While we also have many more aircraft available to measure wind speed near the storm.

Predicting the path a hurricane will take is extremely challenging. However, forecasters continue to improve and now the average error at five days out is 250 miles (400 km). Typically, forecasters determine a storm’s path by integrating satellite, aircraft, and ground-based weather data supercomputer hurricane models. Using all the data, a 3-D model is created to visual the storm. Then forecasters also run simple statistical models based on the tracks of previous hurricanes and plot them together on a map. However, the job is far from complete as an experienced hurricane forecaster has to interpret the models and then produce the “most likely forecast” for the actual storm. The hurricane forecasts are then updated every 6-12 hrs. In 2002, the National Hurricane Center (NHC) introduced the “track cones” which represent the hurricane’s most likely path and also shows the range of possible routes the storm could take with the path down the center of the cone being the most likely path the storm will take.

Interestingly, one of the more serious challenges related to hurricane forecasting is not giving people a definite answer - “communicating uncertainty” – will the hurricane hit (or negatively affect) a specific area or not? Many people unfortunately believe it couldn’t happen to them and they will be fine. Therefore, in order to maintain their safety, people need to clearly understand what the hurricane alert is telling them to do – ultimately, do they need to begin preparing for an evacuation or not? Regardless of what the forecasters predict, people need to be prepared in advance, have plans for themselves, families, and pets, and take responsibility for their own safety.

Based on your knowledge of hurricanes and their devastating effects, explain why and how you should begin to prepare for a hurricane if an initial tracking cone is showing your area as being in the most likely path of a hurricane. Support your position with evidence from the worksheet, your textbook, and the hurricane handouts provided by your teacher. *** ANNOTATION REMINDER *** Task: As you read the reading passages below (indented) in this worksheet use the following Annotation Marks: ? = Question or something confusing ! = Important content/Evidence < >= Unknown Vocabulary ∞ = Connection #= Quantitative Data

Answer all the scaffolded questions as you read! This will help you take valuable notes that you will eventually use to write an argument that introducing a species back to an ecosystem it once inhabited is a good or bad decision.