A new United Nations report details the triple-threat that climate change poses to the ocean and its wildlife.
By Karen HyunVice President, Coastal Conservation, September 25, 2019
Common Murre. Photo: Mick Thompson/Eastside Audubon
As the Climate Action Summit continues this week, the UN has released a new report detailing the effects of climate change on the Earth’s best asset: the ocean. The first of its kind, this report from the Intergovernmental Panel on Climate Change illustrates the need to take dramatic action to protect the ocean, as well as the birds, wildlife and people that depend on a healthy ocean.
The ocean is the earth’s best asset. It covers 70 percent of the planet and provides most of the oxygen we breathe. Since the 1970’s, the ocean has absorbed 90 percent of the warming and a third of carbon dioxide from carbon emissions. If the ocean didn’t absorb almost all of the excess carbon dioxide, average global temperatures would be 60°F hotter. Unfortunately, the ocean can only absorb so much.
Climate change brings a triple-threat to the ocean—rising temperatures, sea-level rise, and ocean acidification—all of which negatively affect birds that rely on the ocean like puffins, murres, and terns throughout their lifecycle.
First, the ocean absorbs excess heat and carbon dioxide from the atmosphere, and that increase in temperature can create big changes for fish and other wildlife. Ocean warming causes declines in oxygen and plankton, which are both crucial to seabirds’ main source of food: forage fish like herring and anchovies. As a result, forage fish populations are declining and moving. This requires seabirds, which nest on land, to travel farther and dive deeper to get their food, expending more energy than they can afford to feed themselves and their chicks.
Second, as the ocean warms, sea ice and other frozen areas around the world begin to melt, causing sea levels to rise. Climate scientists predict that by 2100, sea levels will rise 1-8 feet (depending on future emissions scenarios), flooding habitats of both birds and people. This is especially detrimental to many bird species that nest in low-lying areas like beaches and barrier islands, which are at risk of disappearing under rising seas.
Lastly, excess dissolved carbon dioxide in the ocean creates a more acidic underwater environment, known as ocean acidification. This is bad news for the base of the ocean food web, as many of the tiny plants and animals called phytoplankton and zooplankton have shells that can’t form or dissolve in an acidic ocean. When plankton declines, forage fish populations also decline, leaving seabirds left without enough food to ensure chicks grow into adults.
While the forecast is dire, this is a call to action. We’re not too late to take action on climate change and protect the ocean for the seabirds, wildlife, and people who depend on it. Audubon is already working toward climate solutions:
- Reduce greenhouse gas emissions, especially carbon dioxide, which cause climate change. Audubon supports reaching 50 percent renewable-power generation by 2030.
- Enhance the “natural infrastructure” of our coasts, including wetlands, mangroves, seagrass beds, and marshes that store carbon, buffer coastal communities from the wind and waves of increasing storms, and also provide important bird habitat.
- Establish marine protected areas, which provide undisturbed habitats for seabirds, fish, and other marine life to thrive, and in turn benefit coastal communities and economies.
Seabirds need you—act now and urge your legislators to help protect seabirds by making sure there’s enough forage fish in the ocean for them and other marine life.
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