For decades those of us who walk in Wytham Woods north of Oxford have seen the tags and ribbons, grids and nets, the paraphernalia of the University’s scientific field research dotted around this area of ancient woodland.

But if you have been there in the past year you may have noticed there is rather more than the normal number of tags tied on trees, mesh nets suspended on sticks gathering leaves, even the occasional mammal trap, the humane kind, in some obscure spot. Plus rather more than the normal number of field researchers.

In spring 2008, an international collaboration got under way in the woods — between the HSBC bank and the Oxford-based environmental charity Earthwatch — that is researching the impacts of climate change on managed forest ecosystems.

Five ‘climate centres’ have been set up around the world — in Europe, Brazil, India, China and North America — as the forest component of a five-year-long HSBC Climate Partnership.

Wytham Woods is the European centre. It welcomes ten teams per year of volunteers, made up of HSBC staff from all levels, in Wytham’s case from Europe and the Middle East, who spend two weeks helping scientists gather data and learning about forest ecology hands-on and through lectures. They then act as ‘climate champions’ in their workplaces, enlightening colleagues and community.

At Wytham, three local research partners work with Earthwatch and HSBC: the Centre for Ecology and Hydrology (CEH), the Wildlife Conservation Research Unit (WildCRU) and the Environmental Change Institute (ECI).

I caught up with the latest team, the third this year, to find out what they were doing.

The plan was that I go along and join in. We were to tag and measure and weigh and collect — generally to size up trees or monitor small mammals and insects to see how they respond to changes in weather patterns — all in a day’s work for these climate champions.

The aim is to work out the carbon flow within and out of this temperate woodland. Wytham is fairly typical of a managed north European forest. Dr Dan Bebber, head of climate change research at Earthwatch, said: “The results can help determine how forests can be better managed in an uncertain future.”

I chose a day when the heavens opened; the team had been soaked to the skin the day before and the skies threatened the same that day with the added bonus of hail. So I joined them instead at the John Krebs Centre, the University research centre on the edge of the woods, where they were busy sorting leaves.

Now that does not sound very exciting. But the nine volunteers were just as enthusiastic. After all, they said, it is all part of the scientific process. The leaves, collected in leaf traps last autumn, had been bagged and were waiting for a rainy day. Now they were sorted into type and by plot, to be fully dried and weighed, said ECI forest ecologist Terhi Riutta who was leading the forestry part of the research.

Half the dry weight is carbon, as a rule of thumb, she said. By this means they work out how much carbon returns to the atmosphere when the leaves fall and decompose.

Patterns can be seen over time. For example, if oak trees start losing their leaves earlier in the season it means they have less time to take carbon dioxide from the atmosphere for photosynthesis. Other methods include taking soil samples (to gauge carbon dioxide production through decomposition), and measuring tree diameters, allowing scientists to calculate the carbon stock in the forest.

Mohanned Rahman, of Kennington, was on the team. Other team members came singly or in pairs from Jersey, Leicester, London, Northern Ireland, Armenia and Malta. Mohanned, a financial analyst who commutes daily to HSBC’s head office in Canary Wharf, was sitting with Shane Premchand from Leicester at one of the tables strewn with leaves and seeds, sorting oak from ash, field maple, hazel, hawthorn, blackthorn . . . They were enjoying every moment: the work, the learning, the camaraderie, even getting soaked said Shane.

I asked them how they became climate champions.

“I felt I was now in a position to make real changes in my business area when I got back, to make recommendations on projects,” Mohanned said. “Science has attracted me since I was young. I use a lot of my commuting time to read about science — and I’ll do this more than ever now.

“I got an email from a climate champion from last year who was giving a presentation. Of the ten there I was the one who put his hand up. This was my opportunity!

“The deadline was only a week away, and I had to get the application in — it asks a lot —– and I had to spend lots of evenings working completing projects before I came. But it’s worth it.” For Shane it was the bank’s initiative towards the environment that attracted him to the company in the first place. He said he “jumped at the opportunity” when he heard of the climate champions scheme.

The team’s only disappointment was the small mammal trapping the week before. They had gone out early mornings and evenings setting traps and checking them, 450 traps in all, but caught three wood mice only. They were weighed and released.

This low number was very unusual. Terhi said: “The winter was harsh, but it is too early to tell if it indicates anything.”

So were they now experts on trees? “Probably best not to use that word yet,” said Mohanned, “but I was a complete novice this morning. And I’m going to be looking at trees and everything around me completely differently from now on.”

Shane added: “It’s been eye-opening. We know a lot more than we ever did before. I’m looking forward to sharing it.”

And that is key. These enthusiasts will go away and put into practice action plans: plans that make the link between what they have learnt at Wytham and doing something entirely new within their workplaces to help the environment.

This can be as simple as encouraging others to switch off computers and printers, print on draft to save resources, or re-use or not use plastic cups from the drinks machine, or as complex as redesigning a mortgage system within HSBC, which one London climate champion did last year.

There was no shortage of ideas. Among other ideas, Mohanned says he is thinking of holding regular ‘melting pot’ discussions on the environment, and Shane is considering taking colleagues into his local woodlands to share what he has learnt at Wytham.