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Source: Reuters, April 15, 2008. By Karin Strohecker

World sea levels to rise 1.5m by 2100--scientists

As the climate models start to incorporate dynamic ice characteristics a better picture of the extent of projected sea level rise in the middle term (before 2100) is emerging. This time frame would mean that people born today will potentially live long enough to experience the impacts.

Source: The Guardian (UK) November 12, 2007
Scientists strive for pinpoint warming forecasts
Excerpt below:
"By Alister Doyle, Environment Correspondent
OSLO, Nov 12 (Reuters) - Moving on from the risk of global warming, scientists are now looking for ways to pinpoint the areas set to be affected by climate change, to help countries plan everything from new crops to hydropower dams.

Source: Christian Science Monitor, October 18, 2007. Peter Spotts, staff writer.

Climate models can be more reliable than weather forecasts simply because the long term situation has less uncertainty than the fluctuations of weather patterns. How can you predict global warming if you can't predict rain? explains the increasing certainty that climate scientists expect from their models.
Here is an excerpt:

Teachers: You can download an educational version of one of the climate models that NASA uses and run this in your classroom.
Here is the website at Columbia University: Educational Global Climate Modeling

National Geographic News (December 14, 2006) reports on a new study of potential sea level rise in this century. "[T]he physics of how ice sheets melt and how the oceans will expand in a warmer world is still poorly understood.

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.

Current models don't jibe with actual sea level rise during recent decades, Rahmstorf says. So he crafted a formula based on a relationship between global temperature and sea level seen during the past hundred years.

The model looks at sea level rise from thermal expansion only, noting that ice melt is too difficult to determine:

"In response to greenhouse gas warming, sea level is expected to rise due to the thermal expansion of sea water as the ocean warms. Because the deep ocean will warm much more slowly than the upper ocean, the thermally driven rise in sea level is expected to continue for centuries after atmospheric CO2 stops increasing. To illustrate, Fig. 4 shows the increase of global mean sea level in the GFDL 4xCO2 coupled climate model experiment. Even though CO2 no longer increases after year 140, sea level continues to rise steadily well beyond year 500. The final equilibrium sea level change in the model is 1.9 meters for a CO2 doubling (not shown) which is roughly the level attained in the CO2 quadrupling experiment after 500 years. The equilibrium rise for the quadrupling experiment has not yet been simulated."