Investigating the Effect of Warmer Temperatures on Hurricanes
Skills and concepts that students must have mastered
Atmospheric structure; pressure, winds and Coriolis effect; moisture and latent heat; conditions necessary for the development of a hurricane.
How the activity is situated in the course
Content/concepts goals for this activity
With the completion of this activity students will:
- gain a better understanding of the relationship ocean temperature-hurricane intensity;
- understand why the data available so far do not allow to reach definitive conclusions about what we should expect for the future;
- evaluate other effects of global warming on hurricane damage.
Higher order thinking skills goals for this activity
Other skills goals for this activity
Description of the activity/assignment
Step 1 - Students will download from the web data for a recent hurricane that moved across the Gulf of Mexico (e.g. Katrina) and create a Sea Surface Height (SSH) map of the Gulf at that time using the Colorado Center for Astrodynamics Research. (Note: all links are provided in the "Other Materials" section below). They will plot the positions of the hurricane on the map and add wind speed and atmospheric pressure. They will then analyze the data and discuss the relationship between hurricane intensity and surface temperatures (in the Gulf of Mexico SSH is a good proxy for temperatures).
Step 2 – Formulate a hypothesis on how the global warming of the last century may have affected hurricane intensity.
Step 3 – Test the hypothesis.
- Download from the web and plot on an XY graph data on SST, hurricane intensities and frequency changes in the tropical Atlantic between 1950 and today; identify and discuss similarities and differences. Is there any evidence of a common trend?
- Download from the web and plot on an XY graph the number of landfalls before and after 1950, compare the data to SSTs and discuss if and how this information support previous conclusions.
- Extend the SST and frequency curves back to the 1800s, verify if the pattern(s) previously identified persist (s). Search the web to learn how data were collected before the 1960s, and discuss the reliability of historical data vs. instrumental data.
Step 4 – Consideration of indirect effects of global warming on hurricane damage – the case of higher sea level. Using Google Earth students will analyze how the combination of increased sea level due to a warmer climate and hurricane-induced storm surges will increase the risk of extensive flooding along coastal regions.
Determining whether students have met the goals
Participation in online discussions
Final lab report.