This week we had an apocalyptic report published by the UN into global warming - and what humans, as a species, must do to avoid the worst consequences of it.

I'm afraid I'm very pessimistic about the future of the planet - or at least the future of humanity and civilisation living on the planet - because I really cannot see enough consensus among the 7.8bn people on the earth to make the changes needed.

Actually Britain is reasonably well placed in that the overwhelming majority of people seem to accept that man-made climate change is happening and that "something should be done" to address this.

There are some sceptics who question the scientific consensus - but they tend to be rather at the fringes of society when faced with regular news reports of floods, droughts, wildfires, and melting icecaps on our news programmes.

What is more of a threat in this country is the growing feeling among an increasing number of politicians that while human-made climate change is a phenomenon that is happening in the world, dealing with it is not as urgent as winning the next general election - and that at heart they're more worried about raising the energy bills of their constituents than the future of the planet.

Despite all the fine words I hear coming out of ministers' mouths at present about the COP26 summit later this year, I get the feeling that many in the cabinet feel that way.

What really makes me feel pessimistic about the future is the fact that this country, and indeed Europe as a whole, is only a comparatively small part of the world as a whole.

I've heard many people say: "Why should we change any more? What about China and India - that's where the problems lie!" I can see the logic behind that.

And I can also understand the irritation felt by the leaders of some countries in the developing world who feel they are being lectured about how they should protect the planet by countries who have built up their wealth over the last 200 years by burning as much coal and oil as they could get their hands on!

There are also difficult issues with no simple answers. There is now a rush to manufacture battery cars as new petrol and diesel vehicles are due to be banned from 2030.

But mining or extracting lithium - a vital component for batteries - is an incredibly energy-sapping process. And then you have to get it from far-flung parts of the world, mainly Australia or South America, before it can be made into batteries.

A very high proportion of the total energy consumption of a vehicle is in its manufacture, not in its actual use on the road - which means the energy cost of scrapping a perfectly useable internal combustion-powered car in favour of a battery-powered car (which has an even higher energy cost in its manufacturing process) is very high indeed.

But that really is a sideshow. What the UN report shows us is that if we are to avoid a disaster becoming a catastrophe we have to take global action. That means President Bolsonaro in Brazil banning logging in the Amazon.

That means China and India putting the brakes on their hopes for economic growth for their people - unless they can only use renewable technology. China is aiming for carbon neutrality by 2060 - but by then it will be far too late to prevent serious damage.

And it means the whole world really has to accept a different mindset where economic growth and increased consumption is not seen as desirable.

Is the world ready for that? I really don't think it is.

We may be shocked at the sight of floods in London, Somerset and the south of France. The wildfires in Greece, Turkey and the west coast of America may look shocking on the news.

And reports of temperatures in the mid-40s celsius in Canada may give us food for thought. But on an individual level is there anything we feel we can do as individuals?

My suspicion is that the developed and developing nations will end up tinkering around the edges while the average global temperature continues to rise over the next few decades - but the current crop of politicians will be able to console themselves that they are doing something small safe in the knowledge that by the time the real catastrophe hits we will no longer be around.