(34.0K)
Take a virtual field trip with Google Earth! Google Earth is a free, online application that uses satellite imagery to allow the user to zoom across the globe in a realistic, virtual environment. Downloading Google Earth is free at http://www.earth.google.com. An overview manual is available by clicking here... Google Earth Overview (342.0K)
To continue: - Make sure you have the Google Earth software installed and running. - Copy the following latitude and longitude and paste into the "Fly to" field under the Search tab. - Hit "Enter" for Google Earth to take you to the specified coordinates, then come back here and read the following overview.
Latitude/Longitude: 42.8827, -79.2472
When the fourth (and current) Welland Canal was constructed in 1932, it gave ocean-going cargo ships access to the upper Great Lakes and made cities, such as Detroit, Chicago, and even remote Duluth, Minnesota, sea ports. Today, more than 40 million metric tons of cargo pass every year through the 42 km (27 mi) canal, rising 99.5 m (326.5 ft) in a series of eight locks between Lake Ontario and Lake Erie. This has been an economic boon to inland cities, but also has been an ecological disaster. Ships dump ballast water collected in foreign ports as they take on cargo. In doing so, they have introduced dozens of alien, invasive species into North American inland waterways with devastating ecological consequences. Among the most notorious invasives are sea lampreys, zebra mussels, round gobies, spiny water fleas, and alewives. The most recent invader is a viral hemorrhagic fever specific to fish. This virus—which is something like an Ebola for fish—attacks the endothelial lining of blood vessels and causes massive hemorrhaging and sudden death. It is spreading rapidly throughout the Great Lakes, and we don't yet know how great the damage to fish populations will be.
Textbook Resources
Chapter Activities
Teacher
Student
Please read our Terms of Use and Privacy Notice before you explore our Web site. To report a technical problem with this Web site, please contact the Web Producer.