Sea Level Rise in New England

Last week, I wrote a post discussing climate change and rising sea level, which focuses on the global scale. Back in April, Climatide published a post that discusses four reasons for sea level rise in New England. The author, Heather Goldstone, lists these four phenomena as influences on New England's "above average" sea level rise:

• Rising Ocean Temperatures
• Melting Ice
• Changing Circulation
• Shifting Land

Visit the Climatide article for more!

The Conveyor Belt

In honor of Discovery Channel's Shark Week, the CRE Blog is featuring ocean-related content  this week.

This image, from NASA, shows temperature values in the Gulf Stream.

The Gulf Stream is a warm ocean current that influences the climate on both sides of the Atlantic Ocean. By transporting warm water from Florida, up the United States' eastern seaboard, and across the Atlantic to Europe, this current creates warmer climates than otherwise would be possible from Bermuda to Northern Europe. Click here for maps of current sea surface temperatures in the Gulf Stream.

The Great Ocean Conveyor Belt

The Gulf Stream is one part a Global Conveyor Belt, known as Thermohaline Circulation, in the oceans that moves warm and cold water throughout the Earth's oceans. It is driven by density. Cold, dense water in the polar regions sinks, flows toward the equator, and rises back toward the surface. Warm water originating in the equatorial regions, on the other hand, is less dense and flows across the surface of the oceans toward the polar regions. These currents have a vital impact on the entire global climate. Click the animation above to see it in action!

The Rising Sea

In honor of Discovery Channel's Shark Week, the CRE Blog is featuring ocean-related content  this week.

Loss of land-based ice, like on Antarctica, is one of the driving factors behind sea level rise

Climate is the driver of sea level change. The Earth has alternated between Glacial and Interglacial Periods for millions of years. During a Glacial Period, or Ice Age, much of the water on Earth is trapped in ice sheets and, consequently, sea level drops. Interglacial Periods, on the other hand, are times of warmer temperatures which cause ice sheets to melt. When the ice becomes liquid water, it eventually finds its way to the oceans and raises the sea level. In addition, because the oceans are warmer during interglacial periods, the water expands (known as thermal expansion), which also adds to the sea level rising.

This animation from NOAA shows evidence of loss of ice in the North Pole.

Sea level has steadily risen 1-2.5 millimeters a year since 1900, and it is expected to continue to rise throughout the 21st century. Although there is no perfect model to absolutely predict the future, it is possible to investigate "What If?"

Models based on elevation data can predict what areas could be vulnerable due to rising sea levels.

The Department of Geosciences Environmental Studies Laboratory at the University of Arizona has a web tool that does just that. They have developed a Geographic Information System (GIS) that uses Digital Elevation Models (DEM) to show what areas are potentially vulnerable to sea level change. This web visualization, developed with ESRI's ArcViewer for Flex, allows users to set the amount of sea level rise in one meter increments with a range from no change to six meters.