Biological Oceanography and the Global Carbon Cycle

 

This is a 6-hour enrichment course designed for high school students at the Illinois Math and Science Academy.  It is designed to teach creative thinking and analysis of scientific data while introducing students to the ecology of the open-ocean, the biological carbon pump, and the ways in which climate change may shift the ocean's ability to absorb carbon dioxide.  The course is split into three separate lectures, each of which is followed by a 45-minute group project in which students work in small groups to analyze one of six data sets derived from oceanographic research in diverse locations, including the California Current, the Western Antarctic Peninsula, and the center of the Pacific Ocean.  At the end of each session, the groups re-combine for brief (~5 minute) presentations to their colleagues showing their results.  The course was originally designed to work best with 9-12 students, but can easily be modified to work with different group sizes.  Students will need to have a computer with Microsoft Excel installed.  If you have any questions about the course, are interested in partnering with me, or would like copies of any of the course material, feel free to contact me at: mstukel@fsu.edu

 

Overview of topic material: Algae in the surface ocean are responsible for 50% of global photosynthesis, but because they have short life spans most of the carbon dioxide that they consume will be released back into the surface ocean where it can re-enter the atmosphere.  Long-term carbon dioxide sequestration requires transport of sinking carbon into the deep ocean through the biological carbon pump.  The biological carbon pump transports as much carbon into the deep ocean as human’s are producing every year by burning fossil fuels.  During this session we will learn about the diverse and fascinating organisms that drive this natural feedback on the global carbon cycle.

 

 

Lecture 1: Introduction to the open-ocean

 

This lecture introduces students to the pelagic ocean (the open-ocean far from the land or the seafloor).  The pelagic realm is the largest environment on our planet, yet because it is so different from life on land, it is almost like a foreign planet to most students.  We will cover some of the main reasons that pelagic ecology differs from terrestrial ecology including: ocean currents, the lack of nutrients in most surface ocean waters, the three-dimensional structure of the ocean, the opacity of the ocean, and ocean stratification.  This lecture will also introduce algae and other plankton and discuss why incredibly small-size is an important adaptation of these organisms, as well as the consequence of this small size for pelagic food webs.  Finally, we will introduce the marine carbon cycle.

 

Data sets for analysis:

 Hawaii Ocean Time-series (HOT) Primary Productivity Data

 California Cooperative Oceanic Fisheries Investigations (CalCOFI) Primary Productivity Data

 Palmer Long-Term Ecological Research Program (LTER) Primary Productivity Data

 

 

Lecture 2: The biological carbon pump and the global carbon cycle

 

This lecture focuses on the biological carbon pump (BCP).  The BCP is a diverse suite of processes that transport organic carbon from the surface ocean in to the ocean's interior leading to net carbon dioxide storage in the deep ocean.  We will cover the multiple different pathways of the BCP including sinking particles, active transport by vertically-migrating organisms, and physical transport of organic matter to depth.  The BCP is intimately related to the activities of small animals and microbes in the ocean, who both produce and consume sinking particles.  This lecture will also briefly introduce the marine nitrogen cycle and explore how it intersects with the BCP.

 

Data sets for analysis:

 Hawaii Ocean Time-series (HOT) Particle Flux Data

 Sinking Particle Data from Regions Around the World Ocean

 Palmer Long-Term Ecological Research Program (LTER) Offshore Particle Flux Data

 

 

Lecture 3: Plankton Ecology

 

This lecture focuses on the the diverse organisms that drive open-ocean food webs.  It presents these organisms in an ecological context with a focus on four different groups: phytoplankton (algae) are the primary producers of the open-ocean; protistan zooplankton are the dominant grazers in most of the pelagic realm; metazoan zooplankton (microscopic animals like krill) play many important roles in export and are crucial links to fish and other higher organisms; and heterotrophic bacteria are the dominant recyclers of the ocean.  This lecture introduces many important and unique taxa, such as appendicularians - an organism that lives inside a mucous bubble through which it strains its food.  It also discusses the ecological relationships between taxa and the ways that presence or absence of some of these groups can alter the ocean's ability to absorb and store carbon dioxide.  At the end of this lecture, students break into groups and have a free-form discussion about how climate change might alter marine food webs and carbon sequestration.