Public Release: 

Jaap Sinninghe Damsté awarded the Vernadsky Medal for innovative use of biomarkers

European Science Foundation

In April 2007, the Dutch scientist Jaap Sinninghe Damsté was presented with the prestigious Vernadsky Medal at the European Geosciences Union (EGU) General Assembly. Sinninghe Damsté, from the Royal Netherlands Institute for Sea Research NIOZ, was awarded this medal for his cutting edge work in the field of biogeochemistry.

"It's an honour to win this prize because it is recognition of my science and that it has a certain impact," said Sinninghe Damsté.

Using biomarkers to predict climate change

Sinninghe Damsté received the Vernadsky Medal for his innovative use of biomarkers. Biomarkers are organic compounds found in sediments. With these it is possible to trace back life to its origin. These biomarkers are a kind of organic fossil and unlike normal fossils which only show higher organisms, like dinosaurs, these organic fossils show chemical remains of microbial life like algae, bacteria and archaea. "This really opens new perspectives on all kinds of things. The nice thing about these molecules is that they don't only give the information that a certain organism was present but also about past climatic conditions," said Sinninghe Damsté.

Many of the biomarker compounds come from the membranes of organisms. Because these organisms adjust their membrane compounds according to certain external conditions, it is possible to track a preserved signal in the sediment and learn about the evolution of the organism and even the surrounding environment. The data can then be used to track climate variation going back to at least 100 Million years, a time with much higher CO2 levels. This information could then be used as a model for what we are facing in the future. Understanding the past can help us understand the future.

"We can now look at how warm it was during for example the Cretaceous period which can give indication for climate modelling," said Sinninghe Damsté.

This means it will be possible to predict the implications of the increasing temperatures on Earth today resulting from increased concentration of CO2 in the atmosphere. However, Sinninghe Damsté emphasises that the model has to be validated using past sediments and it's also important to compare this model to as many other proxies as possible as there is always a lot of uncertainty using only one method. If several methods show the same result then it's possible to be more sure about the results.

Applying his knowledge to EUROCORES

Through Sinninghe Damsté's involvement in several different European Science Foundation (ESF) EUROCORES Programmes, it is clear how very versatile these biomarkers are as they can be applied to a whole range of scientific projects.

"Being involved with EUROCORES has been a nice opportunity for my research. Usually the EC programmes only cover limited areas and the programmes have to be more applied. The ESF programmes on the other hand have fundamental science themes. And it's nice to work with different European partners which enlarges your network, it's very good to have these contacts," said Sinninghe Damsté.

For example, through the ESF EuroCLIMATE project CHALLACEA, a group of scientists from across Europe are studying a lake on the hills of Mount Kilimanjaro in tropical Africa. The lake contains sediments which have recorded the transition from the last glaciation (25,000 years ago) until present day. "We are looking at biomarkers in the sediment to find out the climate change during this time period," said Sinninghe Damsté.

The group is also studying the present day lake to understand the whole system in order be able to interpret the record of the lake sediments with more confidence. "We got involved in the project because we developed a so called 'paleothermometer' (a way to track temperature changes) based on archaeolipids. These are biomarkers from very small microorganisms living in the ocean. 3-4 years ago we found they are also present in lakes and we are interested to see if our methods also apply in lake Challa," explained Sinninghe Damsté.

During the 1 ½ year running of the CHALLACEA project, the team has unexpectedly found that they can record the rainfall over time independently from the environmental temperature change using these proxies. During periods of lots of rain, the soil erodes and enters the lake. By looking at soil organic matter entering the lake using a specific compound derived from soil thriving bacteria the team could then compare the specific compound from the soil bacteria present in the lake sediments at different times to calculate how much rain fell at that time. "This seems to be working pretty well and it's really quite interesting to see that at 14,000 years ago there was an increase in rainfall. In the younger Dryas period, conditions returned to mimicking the last glacial and then around 10,000 years ago it became very wet. It was only around 8,000 years ago the rainfall declined and the environment settled into what it's like in the present day," explained Sinninghe Damsté. He also emphasised that these findings still need to be confirmed by other records.

"I like to solve a puzzle and geological records are a kind of puzzle. For example in a core from the Mediterranean seabed you'll see lots of light coloured sediments, then you see a distinct black layer containing lots of organic matter and it's interesting to find out why this black layer was formed. My research is mainly curiosity driven but for example for oil exploration it is also important to know why these organic-rich layers formed because they form the basis for our present-day society as they are the precursor of petroleum," finished Sinninghe Damsté. It is clear that Sinninghe Damste's biomarkers have a range of applications and that there is still a lot more to come from his research. Through cross-discipline collaboration of for example the EURCORORES Programmes EuroCLIMATE, EUROMARGINS and EuroDIVERSITY, Sinninghe Damsté hopes to carry on demonstrating the usefulness of these compounds.

###

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.