Sea Level Rise
Why is Global Mean Sea Level Rising?
Sea level rise is primarily caused by two factors related to global warming: the added water from melting land ice and the expansion of sea water as it warms (NASA). As temperatures rise, land ice - such as glaciers and polar ice sheets - melt and release water into the oceans. Warmer global temperatures also cause the oceans to increase in temperature, which contributes to rising sea levels becuase warmer water expands.
How Fast Will Sea Levels Continue to Rise?
Global mean sea level rise projections vary depending on the type of model used and future scenarios of global temperatures and carbon emissions. The National Oceanic and Atmospheric Science Association (NOAA) projects that sea level will rise between 4-6 feet by the end of the century. More conservative estimates, such as those from the U.S. Army Corps of Engineers (USACE) project a rise in sea level of 1.7-4.8 feet by 2100. The Intergovernmental Panel on Climate Change (IPCC) released in their most recent report that sea levels may rise an average of 2.1 feet by 2100.
Still, the overwhelming majority of climate scientists agree that that global mean sea level is currently rising and will continue to rise. A graph of sea level rise projections from USACE, NOAA and IPCC is shown below:
This projection includes three curves: the IPCC AR5 Median curve as the lowest projection (dashed line), the US Army Corps of Engineers High
curve (solid blue line), and the NOAA High curve (orange line). (Southeast Florida Regional Climate Change Compact 2015)
How Does Sea Level Rise Affect Coastal Communities?
Coastal communities across the U.S are already feeling the effects of rising sea levels, including more frequent flooding, greater storm surges and coastal erosion. Residents of low lying Miami Beach, known as “ground zero” for sea level rise, have become accustomed to sunny-day flooding, in which seawater inundates the streets during high tide even when no rain has fallen. After last fall’s King Tides attracted national media attention for unprecedented sunny day flooding, locals quickly realized that sea level rise has indeed become a reality.
According to Coastal Risk's climate expert, Dr. Leonard Berry, flooding "is not a future problem, it is a current problem." Billions of dollars of coastal assets are at risk from rising sea levels across the United States. Freddie Mac economist discusses rising seas and its potential impact on coastal homeowners below:
Climate Change Explained
What Can You Do?
Governments around the world are already taking action to slow the effects of climate change and become more resilient. At the United Nations COP 21 conference, leaders from over 170 nations gathered to sign the Paris Agreement to reduce greenhouse gas emissions and take steps to adapt to climate change. In the private sector, more companies are committing to sustainability goals and reducing their carbon footprints. Clean and green tech is continually advancing and scientists are working to produce the most accurate and up to date climate research.
At the local level, individuals and communities are mobilizing to prepare for the impacts of climate change - and this is just the beginning. Coastal Risk looks at sea level rise and coastal flooding not as an "imminent doom", but as an opportunity for adaptation. With Coastal Risk's climate vulnerabilty assessments, you too can become better informed on your flood risk and take action to get climate ready and storm safe.
Flood and Hurricane Preparedness
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