I first took part in a protest when I was 16, in 1944. Food was rationed in the UK, but children were given personal points that were saved towards a bar of chocolate once a month. At my school, some of us started collecting our chocolate bars so they could be taken by relief workers and given to German children who were, at that time, literally starving.

Living through the war gave me a sense of the change people were willing to accept when they felt they were working towards a common good. Within a period of months, people had to learn to deal with rationing of food and clothes, and there was suddenly no petrol for private vehicles. Hitchhiking became respectable – my parents, who had owned a car before the war, were happy to thumb a lift. That’s the degree of urgency we need to see now in response to the climate crisis.

In the 70s, I became a member of the Conservation Society, an early British environmental organisation. My wife, Monica, and I fostered a dozen children over the years and adopted six of them. I now have 31 grandchildren, 11 great-grandchildren and three great-great-grandchildren, which helps focus my mind on the future. After retiring from my job as a university lecturer in the 90s, I spent time in the Middle East in refugee camps and villages, where the consequences of a well running dry can be devastating, so I know what’s coming.

Like most people, I became aware of Extinction Rebellion after seeing news reports about their activities. I learned last year that my local XR group in Hastings was going to be staging a series of die-ins across the town, went along and was made very welcome. The event involved a group of us lying down in various public locations, sometimes arranged in a circle holding hands. The young people involved seemed impressed that I was taking part at 91, though there were other pensioners there, and wheelchair users, too.

On marches, I carry a fisherman’s stool in a pack on my back, so I always have something to sit on; I have arthritis and don’t find it easy to stand for long. I’m never without a flask, either. If you’re drinking tea, it’s unlikely anyone is going to think you’re about to start a riot. It’s a technique I learned in Hebron, where I spent time acting as a human rights observer after Monica died in 1999. It’s a real trouble spot, but I got into the habit of buying an ice-cream whenever I was about to approach a checkpoint while escorting children to school – it demonstrated I wasn’t a threat.

I’ve been arrested more times than I can remember over the years. Three years ago, I was charged with aggravated trespass after superglueing myself to another arms trade protester outside the Atomic Weapons Establishment at Burghfield. The most recent arrests occurred during XR events. I was blocking lorries with other older protesters near the docks in Dover; the intention was to draw attention to the danger of extreme food shortages. A couple of weeks later, during the fortnight of direct action in London last year, I was arrested outside the Cabinet Office in Whitehall for refusing to move when asked by police. People online called me a hero afterwards, but that’s just silly. I’m living alone, I’ve got a pension; if you think of the youngsters who’ve got a job to lose, who have a mortgage or rent to pay, along with all the anxieties associated with being arrested in your 20s, that’s a very different order of magnitude.

Experience: I’ve written a letter to my local paper every day for 40 years Read more

I have family members all over the country and some of them take part in XR marches and protests, too. None of them has any great concern about my activities, despite my age. After all, I’ve worked in places where the police and armed forces can be quite trigger-happy. I’ve been told I’m the oldest XR protester; there are so many of us across the country now that I don’t know if there’s any proof of that, though I certainly seem to be the oldest member who’s been taken into custody.

I think Extinction Rebellion have taken a really hopeful step; it’s inspiring to see a movement so driven by young people. It’s important my generation are involved, too – many older people are feeling compelled to protest for the first time and youngsters need to see that happening. After all, our generation is the one that created this crisis. We have a particular responsibility.

• As told to Chris Broughton

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