Oh Buoy, What’s Happening with Sea-Level Rise?

When it comes to climate change, the science is in and the debate is over.

Natal - Brazil / Photo: Canindé Soares

But sometimes when you’re studying the science behind climate change, it’s easy to lose track of the story. Climate change isn’t just a hockey stick graph. It isn’t just global temperature projections or satellite records. Climate change is a story about humans, and it’s a daily reality felt by many.

    The headlines have been all about sea-level rise lately. For #ScienceSunday, let's set sail and look at the facts! pic.twitter.com/rg0xt1Ucux
    — Climate Reality (@ClimateReality) February 28, 2016

Every week, Climate Reality hosts a series on Twitter called #ScienceSunday, where we make the latest climate science simple, one tweet at a time. Recently, we broke down two new studies on sea-level rise – and what they mean for people – with help from our friends at Climate Central. If you missed it because you were taking it easy like Sunday morning, here’s a recap of what happened.
Today, sea levels are rising faster than at any time in the last 2,800 years.


    #ScienceSunday: Today, sea levels are rising faster than at any time in the last 2,800 years https://t.co/8Q6eDd6SoC pic.twitter.com/4m92CBlvwn
    — Climate Reality (@ClimateReality) February 28, 2016

One of the authors of the new study cited in this graphic, Professor Stefan Rahmstorf, said accelerated sea-level rise “was to be expected, since global warming inevitably leads to rising seas.” Here’s a quick break down of what he means:

Carbon pollution from fossil fuel burning and industry is at an all-time high, and both atmospheric carbon dioxide levels and global temperatures have increased dramatically since the Industrial Revolution. Carbon pollution traps more and more heat in our atmosphere, and these warmer temperatures cause glaciers to melt and sea water to expand – leading to sea-level rise.

Sea levels are rising faster than at any time in almost 3,000 years – and the reason why is clear: human-caused climate change.
Sea-level rise is accelerating and worsening coastal flooding worldwide.

    #ScienceSunday: Sea-level rise is accelerating and worsening coastal flooding worldwide https://t.co/8Q6eDd6SoC pic.twitter.com/CLLfc84IzT
    — Climate Reality (@ClimateReality) February 28, 2016

Sea-level rise is happening at a shocking rate. According to NASA’s latest measurements, it’s rising by 3.41 mm per year globally. So there’s a little more water, what’s the big deal? Well, we’re already starting to see dangerous effects like major spikes in coastal flooding worldwide, and researchers have attributed more and more of this flooding to climate change.
There are human fingerprints on thousands of US coastal floods, according to these studies.

    #ScienceSunday: There are human fingerprints on thousands of US coastal floods. New study: https://t.co/Ahi6KBQJdS pic.twitter.com/F0hyU72uSM
    — Climate Reality (@ClimateReality) February 28, 2016

While a huge range of causes can contribute to sea-level rise, these researchers have found that human-caused climate change often tipped the balance in US coastal flooding events. For example, in Wilmington, North Carolina they estimate that there have been 795 days of coastal flooding since 1950 and an incredible 613 have been categorized as human-caused. That means over 75 percent of coastal flood days would not have happened without climate change, according to this study.
When we act on climate, we protect our cities from sea-level rise.

    #ScienceSunday: When we #ActOnClimate, we protect our cities from sea-level rise https://t.co/0UYn5J3eVz pic.twitter.com/GlPDAhNTLQ
    — Climate Reality (@ClimateReality) February 28, 2016

The United Nations Environmental Programme estimates that half of the world’s population lives within 60 kilometers (about 37 miles) of a coast – and three-quarters of all major cities are on a shoreline. If we continue to burn dirty fossil fuels at ever higher rates (“business as usual”), the world’s average temperature is expected to be 2 – 7°C higher than pre-industrial levels. As we mentioned earlier, higher temperatures mean higher sea levels creeping up on great cities from Boston to Bombay.

We took a huge step in the right direction to help mitigate rising sea levels last December. At the UN’s COP 21 climate conference in Paris, representatives from 195 countries across every corner of the world reached a landmark global agreement to reduce greenhouse gas emissions and keep global warming under 2°C.

Read in full here.