Sea level rise

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Map of the Earth with a six-meter sea level rise represented in red
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Sea level is the most concrete and undeniable consequence of global warming. In the United States significant amounts of residential and commercial property lie in the path of predictable sea level rise, particularly in Boston and south Florida. Estimates of the amount of sea level rise by the turn of the 22nd Century range between 2 and 6 feet. The major cause of uncertainty in future projections is doubt about the amount of water which will result from melting of ice sheets.[1] In other parts of the word there are large densely-populated deltas which will be profoundly affected. Globally, dramatic effects have occurred in Venice and can be expected on the coast of Bangladesh

Introduction

Sea level rise refers to an increase in the volume of water in the world’s oceans, resulting in an increase in global mean sea level. Sea level rise is usually attributed to global climate change by thermal expansion of the water in the oceans and by melting of Ice sheets and glaciers on land. Melting of floating ice shelves or icebergs at sea raises sea levels only slightly.

Sea level rise at specific locations may be more or less than the global average. Local factors might include tectonic effects, subsidence of the land, tides, currents, storms, etc. Sea level rise is expected to continue for centuries. Because of the slow inertia, long response time for parts of the climate system, it has been estimated that we are already committed to a sea-level rise of approximately 2.3 |ft for each degree Celsius of temperature rise within the next 2,000 years.[2] IPCC Summary for Policymakers, AR5, 2014, indicated that the global mean sea level rise will continue during the 21st century, very likely at a faster rate than observed from 1971 to 2010.[3] Projected rates and amounts vary. A January 2017 NOAA report suggests a range of GMSL rise of 0.3 – 2.5 m possible during the 21st century.[4]

Sea level rises can considerably influence human populations in coastal and island regions and natural environments like marine ecosystems.[5]