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Climate Change is Here. What Does that Mean for Our Ocean?

U.S. government reports address ocean climate change

Screenshot 2018-11-30 11.23.12
© XL Catlin Seaview Survey

There have been a lot of headlines this week about the 4th National Climate Assessment (NCA 4) report and the Trump Administration’s attempts to bury the report by releasing it the day after Thanksgiving. What hasn’t received as much attention is the significant things this report has to say about the ocean: Most importantly, that ocean climate change is here and promises to grow. While communities are already coping with these changes on the fly, longer-term preparation is key to offset even greater harm in the future.

I’m a climate scientist, and I was a review editor on the NCA 4 report and helped author sections of the other report on the carbon cycle (the 2nd State of the Carbon Cycle Report, or SOCCR-2). I can assure you that these conclusions weren’t developed hastily or carelessly. Over two years, more than 300 authors helped write NCA 4, and more than 200 authors worked on SOCCR-2. Then, the reports were reviewed and reviewed again by the public, federal agencies and other science experts for accuracy and clarity.

Here’s what all ocean supporters should know about what the reports tell us:

  • Ocean ecosystems are being disrupted now by rising temperatures. This is causing loss of important habitats and changing food webs and species distributions. This disruption is going to increase as warming, acidification, and oxygen loss continue. Some examples mentioned in the report include coral reefs systems in Florida, Hawai’i, Puerto Rico, US Virgin Islands, and US Affiliated Pacific Islands, and Arctic ocean sea ice–affiliated changes near Alaska.
  • Marine fisheries and fishing communities face high risk from climate-driven changes in the distribution, timing and productivity of fishery-related species. This will make fisheries harvests less secure and complicate management of fisheries and protected species. Examples discussed in the report include Gulf of Maine cod, Atlantic croaker and Bering Sea Pollock.
  • Marine ecosystems and coastal communities face risk from extreme events associated with high water temperatures, low dissolved oxygen levels, ocean and coastal acidification, coastal flooding and extreme weather events. These extreme events are projected to become more common and severe as these conditions intensify and intersect. In particular, the 2012 North Atlantic heat wave and the 2014-2016 North Pacific heat waves provide examples of this.
  • Coastal oceans and communities are already at risk from rising sea levels. Global average sea level has risen by about 7-8 inches since 1900, with almost half this rise occurring since 1993 as oceans have warmed and land-based ice has melted. Repeated tidal flooding, coupled with sea level rise and heavy precipitation events, threaten America’s trillion-dollar coastal property market and public infrastructure. Superstorm Sandy and the 2017 hurricane season are prime examples of this.
  • Coastal flooding is unevenly distributed across the country, with the Northeast and the western Gulf of Mexico positioned to experience greater sea level rise first accompanied by more frequent and intense flooding. Should sea level rise be on the worse end of projections, most of the U.S. coastline faces strong sea level rise and flooding. Regional differences in sea level rise are caused by ocean circulation, sinking land, precipitation and polar ice melt. Norfolk, Virginia, home of Naval Station Norfolk, is the world’s largest naval station and is already dealing with regular coastal flooding.
  • The impacts of climate change along our coasts are worsening social inequality. Questions of whether to rebuild or relocate and how to pay for adaptation and mitigation to climate change will challenge communities and open new legal and policy questions to answer. Examples of this can be found from every U.S. coastline, where large-scale responses to storms and other extreme events are now needed every year.
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Extreme events in U.S. waters since 2012. The colored areas show the regions impacted by each event, which began with heat waves and led to other extreme events like toxic algae blooms and coral bleaching. © 4th National Climate Assessment, Chapter 9)

It’s clear that ocean climate change is here, and promises to get worse if we don’t act now. It’s natural to wonder where to begin—after all, there’s no time to lose and there are a lot of complexities to address.  Thankfully, we have seen recent efforts to better address climate change. For example, the bipartisan Energy Innovation and Carbon Dividend Act was introduced just this week by Representatives Francis Rooney (R-Fla.), Brian Fitzpatrick (R-Pa.), Ted Deutch (D-Fla.), John Delaney (D-Md.) and Charlie Crist (D-Fla.). This bill would put a price on climate change-causing carbon pollution, thereby reducing the incentive to burn fossil fuels, and refund the money that is earned to American taxpayers. Innovative ideas like this one are out there and they’re increasingly supported by both Republicans and Democrats, meaning that they could potentially pass into law and set us on the path to avoiding the worst of the impacts predicted in the NCA. We at Ocean Conservancy are so glad to see bipartisan innovation like this, and we are working to support more thoughtful proposals to find solutions for climate change and its impacts on the ocean.

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