HOME >> BIOLOGY >> NEWS
Tropical glaciers formed while earth was giant snowball

Boston, Mass. Glacial deposits that formed on tropical land areas during snowball Earth episodes around 600 million years ago, lead to questions about how the glaciers that left the deposits were created. Now, Penn State geoscientists believe that these glaciers could only have formed after the Earth's oceans were entirely covered by thick sea ice.

"There is strong geologic evidence of tropical glaciation at sea level during those times," Dr. David Pollard, research associate, Penn State College of Earth and Mineral Sciences' Environmental Institute, told attendees at the spring meeting of the American Geophysical Union today (May 29) in Boston. "We wanted to determine how low-level tropical glaciers could have formed."

Ice can accumulate in the tropics only if temperatures are below freezing or around freezing with large amounts of snowfall. Tropical glaciers exist today only on high mountain peaks such as the Andes and Mt. Kilimanjaro, and do not reach anywhere near sea level. Pollard and James K. Kasting, professor of geosciences, first looked at the possibility that tropical ice sheets formed before the oceans completely froze into a snowball Earth, when equatorial oceans were still ice-free and could supply enough moisture for substantial snowfall.

During the lead-up to a snowball Earth episode, the Earth gradually cools because the amount of carbon dioxide in the Earth's atmosphere decreases. Relatively fast weathering of silicate rocks on large tropical landmasses causes this decrease that locks up carbon. As the earth cools, the oceans begin freezing. The high reflectivity of the snow and ice that covers the northern and southern oceans, reflects, rather than absorbs, the sun's heat and further cools the planet. This cooling takes place slowly until the oceans are frozen to about 30 degrees latitude, or from the North Pole down to New Orleans, La. and from the South Pole up to the tip of South Africa.

"This is the
'"/>

Contact: A'ndrea Elyse Messer
aem1@psu.edu
814-865-9481
Penn State
31-May-2001


Page: 1 2 3

Related biology news :

1. Tropical legume could be alternative hay/forage crop for Texas
2. Tropical deforestation and global warming
3. Arthropods of Tropical Forests
4. Tropical Science for the 21st Century
5. A Magic Web: The Tropical Forest of Barro Colorado
6. Ira Rubinoff honored by the Association for Tropical Biology
7. Tropical forests under surveillance
8. Tropical scientists find fewer species than expected
9. Sessions on bioterrorism featured at Tropical Medicine Meeting
10. Chemistry in the Amazon: Tropical birds, Amazonian tribespeople derive medicinal benefits from insects, plants
11. Tropical tree distribution could have implications for forest management, conservation

Post Your Comments:
*Name:
*Comment:
*Email:
TAG: Tropical glaciers formed while earth was giant snowball

(Date:12/17/2014)... 16, 2014 Valencell, a leader in performance ... technology to industry leaders such as Intel, Jabra, Atlas, ... biometric wearable products. These products will be showcased at ... Las Vegas . "Our partners ... and robust – with the clinical data to back ...
(Date:12/17/2014)... 2014  Automation is fundamentally transforming the travel ... at international borders. Over the past decade, ePassports, ... veteran travelers to self process through border control ... at an increasing number of airports, seaports, and ... According to Maxine Most , Principal at ...
(Date:12/11/2014)... Dec. 09, 2014 Research and Markets ... ( http://www.researchandmarkets.com/research/twhjll/biometrics_market ) has announced the ... APAC Region 2015-2019"  report to their offering. ... market is advances in technology. With continuous advances ... solutions to the latest standard that meets the ...
Breaking Biology News(10 mins):Valencell PerformTek Biometrics Power the Most Accurate Wearables at CES 2015 2Automated Border Control (ABC) Transforms the Global Travel Experience With More Than 2500 ABC eGates and APC Kiosks Deployed In Airports, Seaports, and Land Borders Worldwide 2Biometrics Market in the APAC Region 2015-2019: Key Vendors are 3M Cogent, NEC, Safran and Suprema 2
(Date:12/17/2014)... (PRWEB) December 17, 2014 Gene ... that it has entered into a technology access ... (ADM) to apply DNA2.0’s proprietary protein engineering technology, ... process. , “We are extremely excited that the ... platform. This proprietary bioengineering technology has now ...
(Date:12/17/2014)... SOUTH SAN FRANCISCO, Calif. , Dec. 17, ... positive results of a Phase 2 study evaluating ... for the treatment of patients with severe, chronic ... the current standard of care, including topical steroids ... endpoint was percent change in Visual Analog Scale ...
(Date:12/15/2014)...  GlassesOff Inc. (OTCBB: GLSO) announced today the appointment ... director of the Company,s Board of Directors. ... its CEO until its acquisition by Stanley Black ... Recognized as the inventor of the first Wi-Fi-based Active ... -based RFID solutions focused on improving operational efficiency, safety ...
(Date:12/13/2014)... (PRWEB) December 12, 2014 Clarassance, a ... announced its new name: Therabron Therapeutics , Inc. ... and bronchioles (a type of structure in the lungs ... company’s mission to develop novel protein therapeutics for the ... directors decided to change the name to mark the ...
Breaking Biology Technology:ADM and DNA2.0 Enter Into Protein Engineering Technology Access and Service Agreement 2Velocity Pharmaceutical Development, LLC and Tigercat Pharma, Inc. Announce Phase 2 Results for VPD-737 in Patients With Chronic Pruritus 2Velocity Pharmaceutical Development, LLC and Tigercat Pharma, Inc. Announce Phase 2 Results for VPD-737 in Patients With Chronic Pruritus 3Velocity Pharmaceutical Development, LLC and Tigercat Pharma, Inc. Announce Phase 2 Results for VPD-737 in Patients With Chronic Pruritus 4AeroScout Founder Joins GlassesOff's Board of Directors 2AeroScout Founder Joins GlassesOff's Board of Directors 3Maryland-based Biotech Company's Path Forward in Treating Respiratory Diseases Sparks Name Change 2
Cached News: