Date:

Ancient oak trees to shed light on the climate of the past 4500 years

Researchers will soon be able to reconstruct the climate of north-west Europe including the UK over the last 4500 years, and to date wooden buildings and objects more accurately, by analysing the chemistry of ancient oak trees, through a new Swansea-led project just selected for €3 million in European funding.

Analysis of tree rings – known as dendrochronology – is an established scientific technique for understanding the past. Tree rings can be examined in living or dead trees, or in objects made of wood, from the beams of a house to the planks of a ship.

The width of the rings indicates how much the trees grew in a particular year, which not only tells us about the climate of the past, but also allows us to date wooden structures and objects from antiquity with extraordinary precision.

However, this approach does not always work well in regions such as the UK and north-western Europe where the climate is mild and rarely limits tree growth. This makes dating challenging and reduces the confidence with which we can use tree-ring width measurements to study the climate of the past.

- Advertisement -

This is where the new project, which is called QUERCUS (Latin for “oak”), will make a difference.

The QUERCUS team will be examining ancient, historic and living oak samples covering the last 4500 years. Oak trees are especially useful as they are widespread across the study region, live a long time and their remains are frequently found in the archaeological record.

The key innovation is that the team will be analysing the chemistry of the wood rather than just the width of the rings. They will be examining the stable (non-radioactive) isotopes of the fundamental elements: carbon, oxygen and hydrogen.

The carbon isotopes in trees indicate changes in carbon assimilation for a given year, which in the UK relates to the amount of summer sunshine. The oxygen and hydrogen isotopes record information on the water used by the tree which indicates the amount of summer rainfall and changes in large-scale atmospheric circulation.

This evidence from the wood’s chemical signature will enable researchers to date the past and to reconstruct summer climate through time.

Crucially, unlike ring width, these isotope signals are just as reliable in trees from areas where growth is not strongly limited by climate. The project will also apply these methods to address long-standing archaeological questions of climate and chronology worldwide.

The team, led by Professor Neil Loader of Swansea’s Department of Geography, includes scientists from the University of Oxford’s School of Archaeology. They will work in close partnership with an interdisciplinary team of experts including representatives of Indigenous groups from across Europe, Aotearoa/New Zealand and the USA.

Professor Neil Loader of Swansea University, who leads the QUERCUS project, said:

“Stable isotopes in tree rings carry strong climate signals and can be used to reconstruct the climate of the past, even when the trees were not growing under environmental stress.

Using this new technique, the QUERCUS project will develop the first annually-resolved tree-ring isotopic chronologies for the UK and north-western Europe, extending back 4,500 years to the Bronze Age.

Our aim is to better understand the climate of the past, and for this we need an improved chronology of when things happened. Our ability to date wooden artefacts and timbers from antiquity will be enhanced significantly through this project. Together we hope that these advances will transform our knowledge of past climate and the dating of wooden artefacts and structures.”

The funding for the QUERCUS project has been approved by the European Research Council (ERC). Set up by the EU, the ERC funds top researchers of any nationality.

SWANSEA UNIVERSITY

- Advertisement -
Mark Milligan
Mark Milligan
Mark Milligan is multi-award-winning journalist and the Managing Editor at HeritageDaily. His background is in archaeology and computer science, having written over 7,500 articles across several online publications. Mark is a member of the Association of British Science Writers (ABSW), the World Federation of Science Journalists, and in 2023 was the recipient of the British Citizen Award for Education, the BCA Medal of Honour, and the UK Prime Minister's Points of Light Award.

Mobile Application

spot_img

Related Articles

Study uses satellite imagery to identify over 1,000 Andean hillforts

A new study, published in the journal Antiquity, uses satellite imagery to survey hillforts known as pukaras in the Andean highlands.

Roman defensive spikes unveiled at the Leibniz Centre for Archaeology

In 2023, archaeologists from Goethe-Universität Frankfurt am Main uncovered a series of wooden defensive spikes during excavations of a 1st century AD Roman fort in Bad Ems, western Germany.

Obsidian blade linked to Coronado’s expedition to find the fabled city of gold

Archaeologists suggest that a flaked-stone obsidian blade could be linked to the expedition led by Francisco Vasquez de Coronado to search for the fabled city of gold.

Clay seal stamp from First Temple period found in Jerusalem

Archaeologists have discovered a clay seal stamp from the First Temple period during excavations in the Western Wall Plaza, Jerusalem.

Offering of human sacrifices found at Pozo de Ibarra

Archaeologists from the National Institute of Anthropology and History (INAH) have uncovered an offering of human sacrifices at the Mexican town of Pozo de Ibarra.

Excavation uncovers preserved wooden cellar from Roman period

Archaeologists from the Frankfurt Archaeological Museum have uncovered a well-preserved wooden celler in Frankfurt, Germany.

Preserved temples from the Badami Chalukya era found in India

Archaeologists from the Public Research Institute of History, Archaeology, and Heritage (PRIHAH) have announced the discovery of two temples dating from the Badami Chalukya era.

Excavation of medieval shipbuilders reveals a Roman head of Mercury

Excavations of a medieval shipbuilders has led to the discovery of a Roman settlement and a Roman head of Mercury.