BBC Look North meteorologist Paul Hudson’s analysis of the climate ahead of COP26

Over 30 years ago, Margaret Thatcher gave a speech on a topic few had heard of or really cared about.

It was 1990 and only the second world climate conference was held in Geneva.

The then prime minister compared the threat of global warming to the first Gulf War that was developing soon after Iraq’s invasion of Kuwait.

She said: “The danger of global warming is still invisible, but real enough that we make changes and sacrifices, so that we do not live at the expense of future generations. “

But, to many, it was a concept that seemed odd – especially to the older generation who had lived through the previous decades.

The winter of 1963 had been so harsh that barrels of beer froze in the Tan Hill pub in the Pennines and some communities were virtually isolated, for weeks, by snowdrifts several meters high amid high winds. flooded from Siberia.

Statistically, it remains the coldest winter of the 20th century.

And then there was the winter of discontent under James Callaghan’s government in 1979, which saw widespread strikes and images of the unburied dead and uncleaned garbage piling up.

But it was also another very harsh winter – heavy truck drivers resort to lighting fires under their vehicles to defrost frozen diesel lines.

Yet for Mrs Thatcher, who was nearing the end of her time in Downing Street when she spoke, the science was already clear.

In the three decades that have passed since his speech, and despite the universal acceptance among scientists around the world that global warming is almost entirely man-made, we find ourselves in what is described as “the living room of the last chance”.

Greenhouse gas emissions have skyrocketed in recent decades and global temperatures have accelerated – a warming that has so far been accurately predicted by powerful supercomputers at the UK Met Office and other organizations weather from around the world.

In Glasgow, at the COP26 summit, governments around the world will digest the latest IPCC climate report, sponsored by the UN and written by some of the world’s leading climatologists.

And that makes the reading gloomy.

Yes, progress has been made in trying to reduce greenhouse gas emissions.

In the IPCC report, the central projection of global temperatures by the end of the century is about 2.7 ° C above pre-industrial levels.

Had it not been for the progress made so far in limiting future greenhouse gas emissions, the central projection would have been that global temperatures would be 4.4 ° C higher than before the industrial revolution.

But scientists insist that if we are to escape the worst effects of climate change, we must keep the temperature rise to no more than 1.5 ° C.

Imagine for a moment what our climate would look like if global temperatures continued to accelerate from where they are today.

Already this year we have seen fierce heat waves across the world.

When I started my career at the Met Office, records were normally broken by about a tenth of a degree.

But in Canada and America’s Pacific Northwest, temperature records have been shattered, some by five degrees Celsius.

Here in Yorkshire in 2019, Sheffield recorded its highest temperature on record in February, highest summer temperature on record and wettest autumn on record, resulting in devastating flooding.

In fact, in surveys that began in 1882, the three wettest falls on record have all occurred since 2000.

All this with global temperatures of around 1.15 ° C above pre-industrial levels.

The reality is that the days of tinkering around the edges are long gone.

The IPCC report makes it very clear that the only remaining scenario that would keep global temperatures below the 1.5 ° C threshold would mean a carbon neutral world by 2050.

But that’s not all. In the second half of the century, we would have to go further – a carbon-negative world.

In reality, that would mean removing more carbon from the atmosphere than we inject.

How will this be possible in less than 30 years?

If governments around the world agree with what scientists are saying, then huge structural changes will need to be made to the global economy and the way we all live, if we are to avoid potentially catastrophic changes in our society. weather.