Climate research

A world of pollen and numbers

John Birks turned 70 in January. In March colleagues from Bergen and abroad honoured him with an anniversary seminar "At the Frontiers of Paleoecology".

John og Hilary Birks in their garden in Bergen in 2002.
John og Hilary Birks in their garden in Bergen in 2002.

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Has the climate always been the same in the past? How have plants and trees behaved and tolerated different types of climate in the past? These are some of the questions professor emeritus John Birks is working on currently. When talking to Birks some months before his 70th birthday, the high-productive professor in quantitative paleoecology announced a slight re-arrangement of his working days after becoming professor emeritus:

“I guess I will slow down a bit. Hilary became emerita earlier this year. We will no longer teach, but we hope to continue our scientific work. I have a large international network, and get involved in many statistical analyses in scientific publications. But I know that I have to start saying no to some projects now”.


At the frontiers of palaeoecology

In March, participants for his anniversary seminar came from Norway, Sweden, Finland, UK, Australia, Netherlands, Czech Republic, Germany, and Switzerland. Many of the lecturers have contributed papers to a special issue of The Holocene (January 2015) entitled ‘At the frontiers of palaeoecology: A special issue to honour H. John B. Birks’ edited by Rick Battarbee, Anne Bjune, and Kathy Willis.

"I am greatly honoured by the large number of former students and reseach colleagues who are coming to the seminar, several of whom are world leaders in their particular branches of palaeoecology, quantitative palaeoecology, pollen analysis and vegetation history, or applied statistics. I am delighted that several modern ecologists with whom I have worked on various modern ecological questions are also coming as I have always tried to combine palaeecology with modern ecology in my research activities" John Birks says. 


Together with his wife Hilary Birks, he is among the veterans at the Bjerknes Centre for Climate Research. The Birks family came to Bergen in the mid 1980s, and the two professors at UiB are leaders within paleoecology.


A pioneer of numerical methods

After finishing their PhD’s in Cambridge in the late 60’s, John and Hilary Birks went to Minnesota, USA.

“When Hilary and I were both post docs in the USA in 1970, we decided to do something else that year having worked on pollen analyses for our PhDs. She went into seeds and fruit, and I studied numerical methods. We have more or less worked in these fields since our time in Minnesota“, John Birks says.

John Birks is a professor in quantitative paleoecology, were data from fossils are used to reconstruct quantitatively the ecosystems of the past. He is among the first in the world to use numerical methods in pollen analysis.

For those not familiar to quantitative paleoecology, how do you do a numerical pollen analysis?

“We have large datasets of pollen counts, and we try to put the handling and analysis of these data on a repeatable basis using numerical techniques. There is a need for quantification in this. As an example, we are using pollen from sediment cores from lakes to tell us something about ecosystems in the past. A climate researcher today does not want to know whether it has been colder or warmer in the past, but by how many degrees was it warmer or colder.”


Investigating future no analogue climatatic situations

In a current project, Birks and his colleagues are investigating plant tolerances under different types of climate in the past. Has the climate in all its components always been the same, is one question they are asking.

“We are working on climate simulations, together with a climate modeller, Paul Valdes, at the University of Bristol. We have climate simulations dating back 12,000 years with very many climate variables. Have, for instance, the combinations of temperature and precipitation always been the same? Ecosystems are not static; they vary both geographically and in time. We are trying to figure out how ecosystems have varied in the past and how they may change under no analogue climatic situations in the future” John Birks says.

The interview is partly based on an interview for the 2° magazine, autumn 2014.