Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Texel paleothermometer for climate reconstruction perfected

Spanish researcher Carme Huguet further refined the recently developed TEX 86 paleothermometer during her doctoral research at the Royal Netherlands Institute for Sea Research (NIOZ). The thermometer measures seawater temperature dependent changes in the cell wall composition of archeabacteria.

Real thermometers have been available since the 17th century. For all periods before this, researchers depend on signs from nature. For such determinations, geochemists resort to molecules from microorganisms whose structure is well preserved in seabeds.

The TEX86 index has recently been developed at Royal Netherlands Institute for Sea Research (NIOZ). It is based on temperature-dependent changes in the lipid composition of the cell walls of certain types of archeabacteria. Their cell membranes are composed from special lipids of which the number of carbon rings in the molecule changes with the temperature of the surrounding seawater.

These organisms therefore adjust the degree of fluidity of their membranes to the prevailing conditions. Carme Huguet studied several aspects of this in greater detail and made significant improvements to the determination.

With a new detection method the analytical reproducibility of the TEX86 paleothermometer was brought to ±0.3°°C and the deviation in the results measured was reduced to 5% of the average. The TEX86 values for organic material out of the water column and from the uppermost layer of the floor sediment best match the temperature of the uppermost 100 m of seawater. However, the small cells of Crenarchaeota cannot sink to the floor by themselves; they are far too light for that.

This is, however, achieved more rapidly if the cells of Crenarchaeota are eaten, for example, by crustaceous zooplankton. Fortunately, the time spent in the gastrointestinal tract of the crustaceans does not harm the molecules. Once they have landed on the sea floor, the preservation of the original fat molecules takes place best in anaerobic sediments.

In modern, anaerobic sediments from a side branch of the Oslo fjord, the measured TEX86 values accurately reflected the average spring-autumn air temperature in Oslo. Temperature estimations of the transition from the last ice age to the present interglacial period were made using two cores drilled from the Arabian Sea. The TEX86 temperatures were compared with values from a British index; the Uk37. The index differences can be explained by differences in the growing season of the archeabacteria and algae that the Uk37 index is dependent on. The upwelling dynamic of the seawater in the Arabian Sea also exerts an influence. This dynamic is strongly dependent on the monsoon season in this area.

Carme Huguet's research makes it clear that climate reconstructions should always be based on comparisons of several types of parallel measurements to prevent unexpected scientific blunders. Determining the surface seawater temperatures in oceans and coastal waters is essential for the reconstruction of historic climate changes and changes in ocean currents. This information is, in turn, vital for perfecting current climate models.

This research was funded by NWO.

Sonja Knols | alfa
Further information:

More articles from Earth Sciences:

nachricht Receding glaciers in Bolivia leave communities at risk
20.10.2016 | European Geosciences Union

nachricht UM researchers study vast carbon residue of ocean life
19.10.2016 | University of Miami Rosenstiel School of Marine & Atmospheric Science

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>