Loved ones said their final farewells to an “extraordinarily intelligent” psychotherapist who dedicated the last decades of his life to alerting others to climate change.

Hundreds gathered in Highgate Village on Friday to celebrate the life of lecturer and climate activist John Mead, who died last month aged 89.

His widow, Catherine Budgett-Meakin, led moving tributes to the “uncompromising” and “thoughtful” man during an eco-friendly funeral service held at St Michael’s Church in South Grove, where the couple married nearly 36 years ago.

His passion for, what he termed, “climate catastrophe” was unrelenting, and dominated the latter half of his life.

Mr Mead’s dedication to the cause was clear on Friday, as his body was brought into the church in an environmentally-friendly wicker casket.

The order of service, printed on 100 per cent recycled paper, featured a photograph of Mr Mead and Ms Budgett-Meakin on their last holiday by aeroplane in 1996 before they gave up all air travel.

In her tribute, Ms Budgett-Meakin, president of the Highgate Literary and Scientific Institution, said: “He was uncompromising, relentless and direct, and I know that he sometimes made people feel uncomfortable.

“One friend, here today, said in his letter to me that John had some of the qualities of an Old Testament prophet.”

She later added: “To misquote a famous woman: there were three in our marriage: John, me and climate change.

“I suspect that there are many people who were influenced by his passion and his single-minded commitment to such an overwhelmingly important issue.

“I’d like to think that is, at least, part of his legacy.”

Mr Mead was born in Blackheath in 1925, but considered west Sussex home after his father moved the family out of London to southern England when he was a child.

He left school at 18 to join the Royal Engineers in 1943, a time he considered to be a “highlight” of his early life.

He was posted to India after studying engineering at Manchester University.

On returning to Britain, he decided against becoming an engineer and returned to university at Oxford to read PPE.

A chance conversation with the Bishop of Durham prompted Mr Mead to go into psychoanalysis, a moment he later said “transformed my life”.

He returned to London, where he took up jobs at the National Coal Board and then as head of the education department at the National Association for Mental Health, which is now the charity Mind.

He then moved into lecturing, and taught liberal studies at Willesden College and then social psychology at South Bank polytechnic.

Following retirement in 1986, he went into private practice as a psychotherapist.

At a house party hosted by mutual friends in 1978, he met Ms Budgett-Meakin. Within the year they were married.

The couple settled in Balham, where they lived for 28 years before moving to Bisham Gardens in Highgate in 2007.

Ms Budgett-Meakin remembered: “He was an extraordinarily intelligent, thoughtful and sensitive man: wise, erudite and witty and a man of great integrity.”