Wednesday August 31, 2022
PhysOrg —
Biological oceanographer Hugh Ducklow studies the marine food web, and how it interacts with the physical properties of the oceans. Much of his work is through the U.S. Long Term Ecological Research Program (LTER), in which researchers have for decades investigated trends across 28 land and marine regions in the United States, along with a few sites elsewhere. In addition to the open ocean, studies encompass deserts, coasts, rivers, forests and grasslands. From 2012 to 2018, while based at Columbia University’s Lamont-Doherty Earth Observatory, Ducklow led the Palmer Station LTER site, the base for yearly cruises through 800 kilometers of icy waters off the Antarctic Peninsula.
To mark the 40th anniversary of the LTER program, researchers just published a series of articles on how climate change is affecting their sites. Ducklow led the section on open-ocean environments, which in addition to Antarctica spans waters off Alaska, California and the U.S. Northeast. We spoke with him about the work, his and colleagues’ observations, and prospects for the future.
Why should we care about what climate change does to the oceans?
Besides the fact that seafood constitutes the major protein source for about 3 billion people, the ocean soaks up a major amount of excess heat and human-generated carbon dioxide. Around 90 percent of all the excess heat produced by the greenhouse effect since the Industrial Revolution is in the ocean. The global ocean has also taken up about one quarter to one third of our carbon dioxide emissions. Both these processes keep air temperatures cooler than they would be otherwise. But they both come with costs. The ocean is warming as a result of added heat. The human-caused warming signal is even detectable in the deep Southern Ocean. Enhanced carbon dioxide uptake is causing ocean acidification. The ecological consequences of warming and acidification are just beginning to be understood, and the future capacity to continue to store heat and CO2 is not certain.