I started watching a National Geographic programme on TV about how the climate had changed over the past centuries. I have always had great respect for National Geographic because its material has always been well researched and presented.

The programme showed how the sea level rose dramatically 125,000 years ago. Geological records showed underwater corals that were frozen in time in rock formations that are now some metres above sea level. Professional geologists explained how science was able to show all this to be true. Up to this point, the programme was good.

Then, suddenly, the programme switched to projecting sea level rise into the future. They came up with a figure of a 1-m sea level rise in the next 100 years. This figure is hundreds of percentage points higher than even the highest serious projection. National Geographic then made a serious error when it said that this sea level rise could occur if the polar ice caps melted. Note the plural. The North Polar ice cap is entirely floating, so, even if it all melted, it would not add to sea level rise at all. When floating ice melts, it does not change the water level. Put a block of ice in a glass of water and watch it.

National Geographic should not have made such an elementary mistake. It went on to imply that we could have a 1-m sea level rise taking place in the next century. National Geographic completely overlooked the first half of the programme, which accurately explained how the sea level rise of 125,000 years ago had taken place over thousands of years and had been shown to be the result a change in the orbit of the earth from nearly circular to more elliptical because of the gravitational influence of the other planets of the solar system interacting with that of the sun. Then the programme showed scary images of walls of water about 5 m high racing down the streets of New York City in seconds. How on earth did National Geographic’s claim of the 1-m rise over a century suddenly turn into 5 m in five seconds? No explanation was given as to where this wall of water came from.

So, a programme that started with well-researched science and was presented by credible scientists suddenly degenerated when National Geographic looked into the future. How sad. My faith in National Geographic took a major knock.

These types of ‘looks into the future’ assume no change in the technology that mankind uses.

In 1910, the Union of South Africa was formed – four years before the outbreak of the First World War. At that time, there were no army tanks, jets or helicopters; the transistor was still way in the future; antibiotics were unknown . . . I could go on. Imagine if, in 1910, people had sat down and wondered how to feed thousands of army horses in 2011 that were destined to pull even larger wooden wagons into battlefield conflicts. Imagine designing the horse and wagon combination to be better protected against the expected onslaught of mounted lancers with new technology lances. Imagine some young officer hesitantly saying that, perhaps, the future soldiers in 2011 would not use lances – they might use some rapid-fire-gun-like thing that could be called a machine gun. He would never have had the insight to propose that, actually, they could use laser-guided smart bombs or ultrahigh-velocity projectiles launched from big machines called tanks, and that these tanks would be supported by flying machines called helicopters, using heat-seeking missiles. He would have been laughed out of the room. It was only a few years before 1910, in 1898, when Winston Churchill, as a young soldier, took part in the last mounted cavalry attack.

In 1910, it was not possible for people to even remotely project their minds to 2011. So, why on earth should we in 2011 be able to accurately project our minds to the year 2111? The technology that people will have adopted by 2111 will be so radically different to anything that we can imagine that it is really silly to try to debate details about it.

There is no credible scientific proposal that comes anywhere near the projection for a 1-m sea level rise. Even the notorious Intergovernmental Panel on Climate Change (IPCC) has reduced its projections to about 15 cm. Over the last few years, the IPCC has always been wrong and has constantly reduced its dramatic projections of doom, so it is probably still wrong now.