Every Monday (well, most of them) we feature a favourite Alex cartoon selected by our readers.

This week’s cartoon, from July 1989, was nominated by reader Sean Brennan, who says he has the original framed in his downstairs loo (he doesn’t specify what material his loo seat is made from).

The Nineties was a funny decade (in both senses). If someone showed you a photo of a street scene in Britain from the 1940s, 1950s, 1960s, 1970s or 1980s and asked you to identify the decade, you’d almost certainly be able to do so: from the clothing, the hairstyles, the types of car, the shop fronts etc. The 1990s was the first decade that didn’t really seem to have its own look (we don’t think we could tell the difference between a street scene from the 1990s and the 2000s or the 2010s). Or maybe we’re just showing our age and the late 80s was the last time we gave any active thought to things like hairstyles or wardrobes.

The Nineties was also an odd decade in that people seemed to have decided what it was going to be like in advance. It was christened the “Nice Nineties” almost before it had started. Perhaps this was the reflection of a collective societal embarrassment about the materialistic excesses of the Eighties, or just an expectation of how human values tend to seesaw from one extreme to another.

The new environmental awareness that the Nineties were promised to provide gave us a welcome source of fresh material for Alex. We had become a bit jaded by writing jokes about Yuppies. Now suddenly we were able to make Penny into an eco-warrior, who hosted meetings of her local environmental group round at Alex’s house, and to reinvent Clive as a “new man” who did group therapy sessions with a bunch of meterosexuals with beards.

We had Alex refer to the ecological concerns of the time as a “fad” on a couple of occasions and it probably was. Though the above strip is nominally about global warming, these were the days before Al Gore’s “An Inconvenient Truth" and people weren’t really aware of the seriousness of climate change. There was a naïveté and feeling of optimism in the air, which led, later in the decade, to Britpop and New Labour. The Cold War and the threat of nuclear annihilation was over (or so it seemed at the time) and people felt they could relax and start worrying about some different danger to the planet. Today both options for global destruction are back on the agenda.

This joke is probably a little facile and the wordplay is not the cleverest we ever devised (normally we’d think up a proper pun or two that linked the concepts), but it amused us to have Alex appearing to express concerns about the environment when he was really being typically snobbish and selfish and just wanting somewhere cosy to sit and read the Sunday papers. And bottoms are reliably funny things to have as the, ahem, butt of a joke.

Charles must have been drawing to a tight deadline that day because there’s not much in the way of background in the cartoon. We were usually up against it back then, trying to think up and draw out the next day’s cartoon before the newspaper’s print deadline at about 8pm. But working under pressure can often produce the best results. John Lennon wrote the seminal Beatles song “A Hard Day’s Night“ the night before the recording session for their new (and then untitled) LP. He was probably also motivated by that other crucial factor in creativity - competitiveness - wanting to beat Paul McCartney to writing the title track for the album.

If you’ve got any suggestions for a favourite cartoon for future inclusion please email us. And do tell us if there’s a particular reason why it appealed to you.