Title: Using Satellite Imagery to Detect and Monitor Red Tide

Author: Eeva Hedefine

Discipline: Life Science

Introduction

Every year algae blooms occur along the coast of Maine and other coastlines of the United States and the world. Red tide can be harmful to marine life, as well as dangerous to humans ingesting shellfish infected with red tide. Satellite imagery has been effectively used to provide early detection of new blooms and subsequent monitoring of those blooms. This has served to limit the exposure and danger to humans.

This activity involves accessing web sites illustrating and discussing satellite imagery of red tide blooms. The images include true color images as well as those depicting concentration levels of chlorophyll and fluorescence. Links to other web sites with further information are provided, allowing students to carry out more in depth research if desired, as well as providing background information on this subject for teachers.

Associated Maine Learning Results

Required Equipment

• Computer (One for each student is preferable.)
• Internet access

Procedure

Have students go to the initial web page: Using Satellite Imagery to Detect and Monitor Red Tide at http://www.spatial.maine.edu/~ehedefin/RedTide.htm. Students can read the introductory material on karenia brevis, one type of phytoplankton responsible for red tide, and the material relating to the Texas Gulf Coast image. They can then examine the satellite image to locate the red tide blooms. After giving the students a few minutes to read the text and view the image, ask them to point out the red tide blooms.

Students can then continue on by viewing the links to the SeaWIFS sensor, one of the sensors used to capture data of red tide blooms, and the current location of the satellite carrying the sensor. The last link takes students to an article “Red Tide near Florida,” which discusses how areas exhibiting high concentration levels of both chlorophyll and fluorescence are indicative of red tide blooms. As the students examine the images, the teacher can discuss how/why chlorophyll and fluorescence are used to identify blooms, from the information provided in the article. Ask the students to interpret the images, identifying the areas relating to red tide blooms. Ask the students if the areas of high chlorophyll concentration in one image correspond to high fluorescence in the other image. Point out to the students that many different types of technology are used to capture different kinds of data. When combined this data allows for more definitive analysis and greater opportunity for reaching either a solution to a problem or providing an improved means of dealing with it.

Expected Results

Students will learn how to interpret satellite imagery to locate red tide blooms in areas corresponding to high levels of fluorescence and chlorophyll. They will be helped to understand why early detection and monitoring of red tide blooms are important to humans. Additionally, students will see how satellite technology is advancing the field of marine biology and providing safeguards for human life. Demo: This can be really messy, therefore, I use it as a demonstration rather than an activity. But it could just as well be an activity for students.

Troubleshooting

The only foreseeable problems that may be encountered are if a particular web site is currently down or the links provided are no longer accessible. In that case, searching for the new site location, such as a search on the article title “Red Tide near Florida,” may provide the new link.

Resources