The Marine Environment: Activity #1 - Setting The Scene
Glacier Bay contains a highly complex oceanographic system within a relatively small area. This in large part explains the unusual variety of marine life that is found here. The ocean's invasion as the glaciers retreated created a complex array of underwater environments, each hosting distinct but overlapping biological communities.
1. The Complex Oceanography of Glacier Bay
2. Influences on the Oceanography of Glacier Bay
Explain to students that each of the four topics is defined by the terms listed under them. For example, under Physical, you would list information about an ocean's tides, currents, salinity, temperature, light, precipitation, etc.
Ask students to find statements that describe the Physical, Chemical, Geological or Biological influences on Glacier Bay's ocean environment. As they make suggestions, write these under each category.
3. Interactions in the Ocean
Ask them to briefly discuss interactions they found as they read the Student Resource: The Ocean - Glacier Bay National Park and Preserve. For example, because Glacier Bay has a large sill at its entrance, (Geological) water entering the bay from the deep, cold and salty ocean is well mixed with water returning to the ocean from the upper bay (Physical).
Working in groups, have them complete the Student Worksheet: Interactions in the Ocean. They can use the Student Resource: The Ocean - Glacier Bay National Park and Preserve and any of the Internet Resources needed to report as many interactions as possible. They will need to read one or both of the following Internet Resources in order to find an interaction between the Biological parameter and the Physical parameter.
4. Glacier Bay - The Amazing Biodiversity Machine
Divide students into groups; give them time to examine the Rube Goldberg machines at the Internet site. Groups are expected to build or design a non-linear machine in which they illustrate the oceanographic interactions they found in Glacier Bay.
GLBA: Nature and Science, Oceans
Glacier Bay National Park and Preserve: Intertidal and Subtidal zones
USGS Marine Habitat
Fjord Processes and Oceanographic Dynamics
Did You Know?
One year of compacted snowflakes creates “firn,” a stage between snow and glacial ice. It takes years of refreezing and recrystallization to result in dense glacial ice.