Guide of SEA LEVEL RISE

NASA - Scientists Get a Real "Rise" Out of Breakthroughs in How We Understand Changes in Sea Level
For the first time, researchers have the tools and expertise to understand the rate at which sea level is changing and the mechanisms that drive that change.
Beyond merely the sloshing of waves that we all recognize along the beaches of the world, sea level describes a complex array of conditions, from chemistry to temperature to changes in the shape of the basins that hold the world's water.
In this visualization, we look at changes in sea level measured from space using data from the TOPEX/Poseidon and Jason satellites.
Sea levels rise and fall as oceans warm and cool and as ice on land grows and shrinks.
Other factors that contribute to sea level change are the amount of water stored in lakes and reservoirs and the rising and falling of land in coastal regions..
'From the Mississippi Delta to the Maldives Islands off the coast of India to the multitude of other low-lying coastal areas around the world, it’s estimated that over 100 million lives are potentially impacted by a three-foot increase in sea level, ' said Dr.
'This is an ideal time, during the midst of an historic year of both related natural events and research developments tied to this critical global issue, to talk to the public about whether ice in our polar regions is truly melting, whether our oceans are indeed rising faster, and what these changes may mean to us.' .


SEA LEVEL RISE

sea level rise: Information from Answers.com
Changes in sea level since the end of the last glacial episode Sea level rise is an increase in sea level .
Sea level has risen around 130 metres (400 feet) since the peak of the last ice age about 18, 000 years ago.
Most of the rise occurred before 6, 000 years ago.
From 3, 000 years ago to the start of the 19th century sea level was almost constant, rising at 0.1 to 0.2 mm /yr.
Since 1900 the level has risen at 1 to 3 mm/yr;[1] since 1992 satellite altimetry from TOPEX/Poseidon indicates a rate of rise about 3 mm/yr.[2] .
Sea level rise can be a product of global warming through two main processes: expansion of sea water as the oceans warm, and melting of ice over land.
Global warming is predicted to cause significant rises in sea level over the course of the twenty-first century..
Local and eustatic sea level Water cycles between ocean, atmosphere, and glaciers .
Local mean sea level (LMSL) is defined as the height of the sea with respect to a land benchmark, averaged over a period of time (such as a month or a year) long enough that fluctuations caused by waves and tides are smoothed out.
One must adjust perceived changes in LMSL to account for vertical movements of the land, which can be of the same order (mm/yr) as sea level changes.

.

info: SEA LEVEL RISE


Photo by www.hackensackriverkeeper.org

Sea Level May Rise 40 Percent Higher Than Predicted, Study Says
Most sea level models predict changes based on what we know about how ice sheets melt and warmer waters expand.
These models suggest that by 2100 sea level will be between 4 and 35 inches (9 and 88 centimeters) higher than it was in 1990.
So Stefan Rahmstorf, an ocean physicist at Potsdam University in Germany, took a different approach: He used studied actual observations of changes in sea level collected in the 20th century to make predictions for the 21st century.
So he crafted a formula based on a relationship between global temperature and sea level seen during the past hundred years.
'The more the temperature rises, the faster the sea level rises, ' he said.
His results predict that by the end of the century sea level will rise between 20 and 55 inches (50 and 140 centimeters) above 1990 levels.
'We have much larger uncertainty than we previously thought about the sea level, ' Rahmstorf said.

Benefits



SOTC: Global Sea Level
NSIDC's Climatology and Meteorology Glossary: Search and browse terms related to climatology and meteorology in NSIDC's comprehensive cryospheric glossary..
Global sea level is currently rising as a result of ocean thermal expansion and glacier melt, both caused by recent increases in global mean temperature.
If these ice sheets melted entirely, sea level would rise by more than 70 meters..
Image courtesy of the Mark Dyurgerov, Institute of Arctic and Alpine Research, University of Colorado, Boulder..
The network of small glaciers described in Mountain Glaciers has a total area of only 785, 000 square kilometers, making up about four percent of the total land ice area (Dyurgerov 2002 ); however, these lower latitude glaciers may have contributed as much as 40 percent of the total sea level change in the last decade of the 20th century..
Global mass balance data are transformed to sea-level equivalent by multiplying annual average mass balance (approximately -190 millimeters for the period 1961 to 2003) by the surface area of these 'small' glaciers (785, 000 square kilometers).
When dividing this value by the surface area of the oceans (361.6 million square kilometers), the final result is 0.4 millimeters of sea level rise per year.

SEA LEVEL RISE: