Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Snapshot of past climate reveals no ice in Antarctica millions of years ago

29.07.2008
A snapshot of New Zealand’s climate 40 million years ago reveals a greenhouse Earth, with warmer seas and little or no ice in Antarctica, according to research published this week in the journal Geology.

The study suggests that Antarctica at that time was yet to develop extensive ice sheets. Back then, New Zealand was about 1100 km further south, at the same latitude as the southern tip of South America – so was closer to Antarctica – but the researchers found that the water temperature was 23-25°C at the sea surface and 11-13°C at the bottom.

“This is too warm to be the Antarctic water we know today,” said Dr Catherine (Cat) Burgess from Cardiff University and lead-author of the paper. “And the seawater chemistry shows there was little or no ice on the planet.”

These new insights come from the chemical analysis of exceptionally well preserved fossils of marine micro-organisms called foraminifers, discovered in marine rocks from New Zealand. The researchers tested the calcium carbonate shells from these fossils, which were found in 40 million-year-old sediments on a cliff face at Hampden Beach, South Island.

“Because the fossils are so well preserved, they provide more accurate temperature records.” added Dr Burgess. “Our findings demonstrate that the water temperature these creatures lived in was much warmer than previous records have shown.”

“Although we did not measure carbon dioxide, several studies suggest that greenhouse gases forty million years ago were similar to those levels that are forecast for the end of this century and beyond.

Our work provides another piece of evidence that, in a time period with relatively high carbon dioxide levels, temperatures were higher and ice sheets were much smaller and likely to have been completely absent.”

The rock sequence from the cliff face covers a time span of 70,000 years and shows cyclical temperature variations with a period of about 18,000 years. The temperature oscillation is likely to be related to the Earth’s orbital patterns.

The research was funded by the Natural Environment Research Council, the Netherlands Organisation for Scientific Research (NOW) and GNS Science, New Zealand.

Issued jointly by the Natural Environment Research Council and Cardiff University.

Marion O'Sullivan | alfa
Further information:
http://www.nerc.ac.uk

More articles from Earth Sciences:

nachricht Rare Earth Elements in Norwegian Fjords?
06.08.2020 | Jacobs University Bremen gGmbH

nachricht Rock debris protects glaciers from climate change more than previously known
05.08.2020 | Northumbria University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: ScanCut project completed: laser cutting enables more intricate plug connector designs

Scientists at the Fraunhofer Institute for Laser Technology ILT have come up with a striking new addition to contact stamping technologies in the ERDF research project ScanCut. In collaboration with industry partners from North Rhine-Westphalia, the Aachen-based team of researchers developed a hybrid manufacturing process for the laser cutting of thin-walled metal strips. This new process makes it possible to fabricate even the tiniest details of contact parts in an eco-friendly, high-precision and efficient manner.

Plug connectors are tiny and, at first glance, unremarkable – yet modern vehicles would be unable to function without them. Several thousand plug connectors...

Im Focus: New Strategy Against Osteoporosis

An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.

Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...

Im Focus: AI & single-cell genomics

New software predicts cell fate

Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...

Im Focus: TU Graz Researchers synthesize nanoparticles tailored for special applications

“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.

Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...

Im Focus: Tailored light inspired by nature

An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“Conference on Laser Polishing – LaP 2020”: The final touches for surfaces

23.07.2020 | Event News

Conference radar for cybersecurity

21.07.2020 | Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

 
Latest News

Rare Earth Elements in Norwegian Fjords?

06.08.2020 | Earth Sciences

Anode material for safe batteries with a long cycle life

06.08.2020 | Power and Electrical Engineering

Turning carbon dioxide into liquid fuel

06.08.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>