Navigation Links
New research lowers past estimates of sea-level rise
Date:3/16/2012

The seas are creeping higher as the planet warms. But how high could they go?

Projections for the year 2100 range from inches to several feet, or even more.

The sub-tropical islands of Bermuda and the Bahamas are two seemingly unlikely places scientists have gone looking for answers.

The cliffs and ancient reefs on Bermuda and the Bahamas have lured fossil-hunters for decades. The land on the Bahamas, for example, has a foundation of fossil coral; the stone is derived from the disintegration of age-old coral reefs and seashells.

These areas are now attracting scientists investigating global sea level rise.

By pinpointing where the shorelines stood on cliffs and coral reefs in the Bahamas and Bermuda during an extremely warm period 400,000 years ago, researchers hope to narrow the range of global sea-level projections for the future.

After correcting for what they say was sinking of these islands at that time, scientists estimate that the seas rose 20 feet to 43 feet higher than today--up to a third less than previous estimates, though still a drastic change.

The study infers that the Greenland and West Antarctica ice sheets collapsed during the ancient warm period, but that ice loss from the vast East Antarctic Ice Sheet was negligible.

The results are reported in this week's issue of the journal Nature.

"Our research provides a simple explanation for high beach deposits [such as fossils in the Bahamas]," said the paper's lead author Maureen Raymo, a scientist at Columbia University's Lamont-Doherty Earth Observatory.

Average global sea-level rose eight inches since the 1880s, and is currently rising an inch per decade, driven by thermal expansion of seawater and melting of glaciers and ice sheets, including the still mostly intact ice in Greenland and West Antarctica.

In its most recent report, the Intergovernmental Panel on Climate Change estimated that the seas could rise up to two feet by 2100.

That number could go higher depending on the amount of ice melt and the quantity of greenhouse gas emissions.

The United Nations estimates a five feet sea-level rise would be enough to swamp 17 million people in low-lying Bangladesh alone.

The new study factors in the loading and unloading of ice from North America during the ice ages preceding the long-ago sea-level rise.

As the ice sheets grew, their weight pushed down the land beneath them while causing land at the edges--Bermuda and the Bahamas--to bulge upward, says Raymo.

When the ice pulled back, the continent rebounded, and the islands sank.

"We're re-thinking many of our estimates of past sea-level rise now that we're more aware of the effects of unloading of ice," said Bil Haq, program director in the National Science Foundation's (NSF) Division of Ocean Sciences, which funded the research. "We now have a meaningful way of calculating the rebound.

"This study is a good example of collaboration between paleoceanography and geophysics to resolve an important issue: the question of future sea-level rise."

Today, both Greenland and West Antarctica are losing mass in a warming world, but signals from East Antarctica are less clear.

Raymo said the research helps show that "catastrophic collapse" of the East Antarctic ice is probably not a threat today.

"However, we do need to worry about Greenland and West Antarctica."


'/>"/>

Contact: Cheryl Dybas
cdybas@nsf.gov
703-292-7734
National Science Foundation
Source:Eurekalert  

Related biology news :

1. Researchers print live cells with a standard inkjet printer
2. Researchers uncover molecular pathway through which common yeast becomes fungal pathogen
3. Exposure to antibiotics linked to severity of allergic asthma: UBC research
4. MIT research: The power of being heard
5. Ottawa researchers to lead world-first clinical trial of stem cell therapy for septic shock
6. UNH researchers find African farmers need better climate change data to improve farming practices
7. UNH research adds to mounting evidence against popular pavement sealcoat
8. Breakthroughs in Chikungunya research from A*STAR spell new hope for better treatment and protection
9. Researchers attempt to solve problems of antibiotic resistance and bee deaths in one
10. Scripps Research discoveries lead to newly approved drug for infant respiratory distress syndrome
11. A project to research biological and chemical aspects of microalgae to fuel approach
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
New research lowers past estimates of sea-level rise
(Date:3/6/2017)... , March 6, 2017 Mintigo ... technology, today announced Predictive Sales Coach TM , ... actionable sales intelligence into Salesforce. This unique AI ... their sales organizations with deep knowledge of their ... for intelligent engagement. Predictive Sales Coach extends Mintigo,s ...
(Date:3/2/2017)... , March 2, 2017 Australian stem cell ... (ASX: CYP), has signed an agreement with the Monash ... Monash Biomedicine Discovery Institute and Department of Pharmacology at ... a further preclinical study to support the use of ... asthma.  Asthma is a chronic, long ...
(Date:2/28/2017)... Spanien, 27. Februar 2017  EyeLock LLC, ein marktführendes ... seine erstklassige biometrische Lösung zur Iris-Erkennung auf ... X16 LTE auf dem Mobile World Congress ... Qualcomm-Stand in Halle 3, Stand 3E10, vorstellen. ... Sicherheitsplattform Qualcomm Haven™ – eine Kombination aus ...
Breaking Biology News(10 mins):
(Date:3/24/2017)... Biotech Ltd. ("Sinovac" or the "Company") (NASDAQ: SVA), a leading provider ... that its board of directors has amended its shareholder rights plan. The ... 2017 to March 27, 2018. The amendment was not in response to ... ... Ltd. is a China -based biopharmaceutical company that ...
(Date:3/24/2017)... 24, 2017 Agenus Inc. (NASDAQ: AGEN), an ... and cancer vaccines, today announced participation at the following ... William Blair and Maidstone Life Sciences conference "Cancer Immunotherapy ... New York, NY . Agenus will ... at 9:40 am: Robert B. Stein , M.D., ...
(Date:3/23/2017)... 2017 Research and Markets has announced ... report to their offering. ... The Global Market for Bioproducts Should ... at a CAGR of 8.9%, This research ... into seven major product segments: bio-derived chemicals, biofuels, pharmaceuticals (biodrugs ...
(Date:3/23/2017)... March 23, 2017  GlobeImmune, Inc. today announced it ... sale of 12,835,490 shares of its common stock to ... companies. In connection with the sale of its common stock, ... and issue to GlobeImmune 200,000 shares, an estimated $2.0 ... "We are pleased to enter into this strategic ...
Breaking Biology Technology: