Coastal Hazards
GEOL 103 Laboratory Overview
Learning Goals
In this module, you will:
- identify causes for ocean circulation and explain the influence of ocean currents on weather & climate
- learn and identify how and why coasts change
- evaluate types of hazards that occur along shorelines
Tropical Cyclones
Introduction
Tropical cyclones are one of the most destructive phenomena that impact millions of people around the world. They are fueled by the warm tropical waters in the world's oceans, pack enormous energy and when they make landfall, they deliver that energy onto land and all structures in the forms of deadly storm surge, torrential rain, and terrifying winds. As the world's population increases and the climate system warms, the intensity and frequency of these coastal storms are also increasing. Below is a brief introduction to hurricanes by National Geographic.
Hurricanes 101 | National Geographic
Hurricanes in the news
Below are some examples of recent hurricanes, with a focus on the southeastern coasts of the US.
Hurricane Hugo
Hurricane Hugo is one of the strongest hurricanes to make direct landfall along coastal South Carolina. The landfall occurred directly northeast of Charleston near Sullivan's Island as a Category 4 hurricane. Because of the proximity of the hurricane to Charleston, this area saw severe damage to property and loss of life. SC DNR created a Story Map to commemorate the 30th anniversary. See full Story Map at https://arcg.is/0nSCLW .
2017 Hurricane Season
2017 was one of the strongest Atlantic hurricane seasons on the record. Six of the ten hurricanes that made landfall in 2017 were major hurricanes (Category 3 or higher), causing more than 3300 deaths and $300 billion in damages. Houston region and Puerto Rico were particularly hard hit - Puerto Rico is yet to fully recover from this disaster.
Hurricane tracks of the major hurricanes (Category 3+) that developed in the Atlantic in 2017. Click on the map and explore the tracks.
2020 Hurricane Season
For the fifth year in a row, the 2020 hurricane season had above-average hurricane activity. In 2020, the season was so strong that the National Weather Service ran out of 26 assigned hurricane names for significant storms. The 2020 Atlantic hurricane season smashed records with an unprecedented 30 named storms. The National Weather Service noted that every mile of the U.S. Atlantic coast was under a tropical watch or warning in 2020. NOAA reported the most billion-dollar disasters in the U.S. in a single year in the 40 years of record-keeping, with significant contributions from the five storms that made landfall in the U.S. The NASA animation shows the named storms and their tracks. Also, note the colors of the oceans that indicate warm waters that provide fuel for these storms.
Primer on Coriolis Effect and Hurricanes
A short video about the Coriolis Effect that impacts atmospheric currents on Earth.
ABC News video on how hurricanes form.
Global Circulation Patterns by UK Met Office
Part I: Differential heating
Part II: The "Three Cells"
Part III: The Coriolis Effect and Winds
Hurricanes and Oceans
Below is a map of all the recent hurricane tracks within the Indian, Pacific, and Atlantic basins. Zoom into the map to identify the hurricanes (or cyclones or typhoons as they are called in other parts of the world.)
Hurricanes in the World (up-to-date for this year).
The map below highlights the areas of the oceans where sea surface temperatures (SST) vary depending on the latitude. Hot colors (reds) indicate higher temperatures while cold colors (blues) indicate lower temperatures. Note the directions of various currents that develop in various parts of the ocean basins. North-South trending currents tend to move cold and warm waters from the polar regions to the equator, while the East-West trending currents typically do not exchange heat. However, the thermocline (sloping boundary of warm surface waters and colder deeper waters) along the equatorial Pacific Ocean can influence the climate system regionally.
Ocean Currents and Sea Surface Temperatures
Coastal Erosion
Erosion caused by waves along our coastlines has a major impact on our economies. The normal erosion on the beaches caused by wave action is exacerbated by coastal development, rising sea levels as well as increased frequency and intensity of coastal storms. Watch this quick video that summarizes some of the processes and how we have come to adapt.
How Coastal Erosion Works