The ocean naturally absorbs gasses from the atmosphere. When this occurs, the dissolved gasses react with seawater and various compounds in it. Since the ocean is extremely huge, covering about three-quarters of the planet, gasses that dissolve in it from the air usually don't change the seawater in any big way. But since recently there is an extremely and ridiculously excessive level of carbon dioxide in the air, like billions of tons, well, actually, 236 petagrams, or 236 trillion kilograms, or 260,100,000,000 tons added since 1750, it turns out that carbon dioxide gas is changing seawater chemistry. It decreases the pH and makes it more acidic. How will this affect marine life? It is difficult to say, but it is generally accepted right now that it will negatively affect calcifying plankton. This can mean big trouble for anything that relies on plankton for food (i.e., everything in the ocean).
I am now planning an OA experiment that will test if predatory snail populations are affected by seawater pH. Maybe their prey choice depends on seawater pH, which could mean they are differentially structuring prey populations throughout their range as a result of the changing climate. I also want to test if there are site-specific differences in their reactions that could be due to a genetic predisposition.
Here are some pictures from this summer's course! Most of the photos are by one of the students who took the course with me, Jack Koch, who now attends Oregon State University.
|Learning to use pH equipment in the field.|
|Measuring the pH of tidepools at Deadman Cove.|
|A fishing boat off the west side of the island.|
|A sea plane, possibly with Mt. Baker in the background on the left.|
|Islands in the San Juan Archipelago.|
|On San Juan Island.|
|Most of my classmates on a short hike around the labs.|
The following photos are by Alexandra Bausch (but not the anemone photo):
|Kayak trip to see orcas.|
|Jack Koch, the great photographer who took many of the pictures above!|
|A ferry arriving at Friday Harbor.|
|My favorite instrument: the bull kelp horn!|
There are no pictures of the experiment I did with anemones during the course, which is unfortunate but not surprising given that one usually only thinks to take pictures of play and not work. But here is an anemone we did not experiment on!
I just noticed there are a bunch of Nucella canaliculata cuddling up next to the anemone. Cuteness!
1. Howes, E. L., Joos, F., Eakin, M., & Gattuso, J.-P. (2015). The Oceans 2015 Initiative, Part 1, (March).