Hurricanes
by Olivia Reed and Jacqueline Palmer
1. Have You every Wondered How Hurricanes Form?
2. In 2005, a record of 15 hurricanes formed. Six of those hurricanes directly hit the U.S.: Cindy, Dennis, Katrina, Ophelia, Rita, Wilma. Three of those hurricanes reached the status of a category 5 hurricane: Katrina, Rita and Wilma. All of the hurricanes that hit the U.S. caused $143,589,000,000 worth of damage, but the most damage came from hurricane Katrina.
3. Hurricanes form around the spring and fall seasons. They form along the equator. More specifically, they form and travel to the Eastern Pacific, Western Pacific, Southern Pacific, Northwestern Atlantic, and Indian Ocean.
4. Hurricanes can only form under the right conditions. Hurricanes form when there are winds blowing in the same direction over warm water that is at least 150 feet deep and 82 degrees Fahrenheit. Warm, humid air above the ocean's surface rises. This leaves less air near the surface, creating a low pressure area below. Warm air from the surrounding areas pushes into the low pressure area. That new air becomes moist and rises, too. As the new air continues to rise, surrounding air swirls in to take its place. Eventually, the warm and moist air will turn into clouds. This system of clouds will spin and grow more and more, fed by evaporating water from the ocean's surface. You can see this in the picture above.
5. There are 5 catigories that a hurricane can fall under. Hurricanes are measured based on their wind speed. Below is the Saffir-Simpson scale for categorizing hurricanes.
Category 1: Winds 119-153 km/hr
Category 2: Winds 154-177 km/hr
Category 3: Winds 178-208 km/hr
Category 4: Winds 209-251 km/hr
Category 5: Winds more than 252 km/hr
6. So, what is the purpose of this activity?
The purpose of this activity is to examine authentic sea surface temperature data to explore how hurricanes extract heat energy from the ocean surface.
Partner 1 (Olivia)
1. Is there evidence of a change in sea surface temperature (SST) in the data maps?
Yes, on the daily surface temperature graph it showed that the temperature dropped from 29.5 to 25.8 degrees celsius from the 24th to the 25th of September. Also there were shifts In temperature with the thermal graphs because it went from orange to greenish yellow as the hurricane moved inland.
2. Describe the change between the hurricane passage and the effect on SST?
It is very subtle but you can see that the SST is getting less orange and more green and yellow. That means that as the hurricane moves inland, the colder the SST gets. The line graph shows that the temperature dropped from 29.5 to 25.8 degrees celsius from the 24th to the 25th of September which means the SST dropped in temperature. After the hurricane passes which was around the 28th, the temperature began to rise again and then it spiked up again on the 30th.
Partner 2 (Jacqueline)
1. Explain the effect on the temperature in your line plot after the hurricane passed. The effect of the hurricane passing over longitude 90W (-90) and latitude 27N was that the temperature dropped drastically. It went from 29.5°C on September 17 to about 25.3°C on September 25. The days the hurricane went through the Gulf of Mexico from September 18 to September 24, 2005.
Question 1 (Olivia)
What conclusions can you make about how hurricanes extract heat energy from the ocean?
Energy can never be destroyed, it just changes form. We see this when a hurricane extracts heat energy from the ocean and transfer it into the atmosphere. The sun warms the ocean by giving off energy. The warm moist air from the ocean is what fuels a hurricane. As the hurricane grows, it uses up that energy therefore making the SST drop in temperature.
Question 2 (Jacqueline)
What other effects on SST may be occurring?
Some factors that affect the SST of an ocean other than hurricanes include the sun, the seasons, and clouds. The sun heats the water, so a direct hit from sunlight will warm the water. If clouds block the sunlight, the water won't receive direct sunlight, and therefore won't be as warm. Similarly, the seasons affect how warm the water is because the seasons are when the earth is tilted towards or away from the sun.
Bibliography
Dunbar, Brian. "What Are Hurricanes?" NASA. NASA. Web. 13 Jan. 2016. <http://www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-are-hurricanes-58.html>.
"When and Where Do Hurricanes Occur?" AccuWeather. AccuWeather. Web. 13 Jan. 2016. <http://www.accuweather.com/en/weather-blogs/hurricanefacts/when-and-where-do-hurricanes-o/31028>.
"2005's Record-Breaking Hurricane Season: By the Numbers." The Weather Channel. Weather.com. Web. 13 Jan. 2016. <http://www.weather.com/storms/hurricane/news/2005-hurricane-season-by-the-numbers>.