Center For Ocean Sciences Education Excellence COSEE Ocean Systems
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Oxygen Minimum Zones
Presented by Dr. Carl Lamborg and Dr. Dan Ohnemus - Thursday, May 7, 2015

In this webinar, the presenters joined forces to tackle an element vital to ocean health and productivity: oxygen. The two-part presentation focused on two types of “Oxygen Minimum Zones”: those that result from natural phytoplankton blooms and those in the nearshore that are tied to human activities. In the latter, pollutants such as mercury can become concentrated, thus it is important to understand how organisms throughout the food web are affected.

This webinar included a case study from Dr. Lamborg’s research in Long Island Sound, as well as data collected by Dr. Ohnemus during a GEOTRACES cruise in the South Pacific Ocean. Learn more about accessing other GEOTRACES data by clicking here.

Webinar Archive

You can watch the archived video of the webinar below. Below the video is the concept map that was presented, so that you can follow along with the video.

Click here (PDF, 64 KB) for a transcript of the Q&A portion of this video.

Concept Maps

This webinar featured a concept map used to frame the presentation. To view the map in full screen, click on the light blue wrench and select Open Full Map Viewer. Click on the concepts to access additional resources embedded in the map. To save this map to your CLIMB account, click the blue wrench in the upper left corner and select Copy Map to My Maps.

What is an Oxygen Minimum Zone and Why Does it Matter?

This two-sided concept map highlights two types of low-oxygen areas. The left side outlines the process that occurs when large phytoplankton blooms leave areas devoid of oxygen in the open ocean, and the right side illustrates the conditions and impacts of a human-induced hypoxic event.


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About the Presenters

Carl Lamborg 

Carl Lamborg is an Assistant Professor in the PBSci-Ocean Sciences Department, Institute of Marine Sciences, University of California, Santa Cruz. He holds a Ph.D. in Oceanography from the University of Connecticut and an M.S. in Environmental Chemistry from the University of Michigan. His specialties include atmospheric and aquatic chemistry, biogeochemistry, and trace element cycling in the environment.

Dan Ohnemus 

Dan Ohnemus is a post-doctoral researcher in the Twining Laboratory, Bigelow Laboratory for Ocean Sciences. He received a Ph.D. in Chemical Oceanography from MIT/Woods Hole Oceanographic Institution and a B.A. in Biology and Chemistry from Williams College. His research interests focus on the interactions between biotic and abiotic marine particles.