What I've learned after 40 years as the Observer's science editor

The Guardian

13-04-2025

Earlier this year I received an email from a reader asking background questions about an article I had written more than four decades ago. Given the time gap, my recollection was hazy. To be honest, it was almost non-existent. So I was intrigued – and then astonished when I read the feature.
I had written about the British glaciologist John Mercer, author of a 1978 Nature paper in which he warned that continuing increases in fossil fuel consumption would cause amounts of atmospheric carbon dioxide to soar. Global temperatures could rise by 2C by the mid-21st century, causing major ice loss at the poles and threatening a 5-metre rise in sea levels, he warned.
Today temperatures are 1.5C warmer than they were in ­preindustrial times and sea ­levels are rising at an accelerating rate. And, as Mercer also predicted, global warming is having its greatest impact at the poles. Ice is disappearing, threatening to inundate Earth's populated coastal zones with meltwater and compromising the planet's ability to reflect solar radiation back into space. Further temperature rises are likely to ensue.
Mercer was not the first scientist to warn that our world faced a greenhouse future, but his paper, with its highly specific forecasts, was my earliest exposure to a detailed examination of the concept. In the late 70s, most climatic fears were focused in the media on the arrival of a new ice age. Mercer – then based at the Institute of Polar Studies at Ohio State University – predicted the opposite. Ours would be a hot and humid future, he insisted. That grim forecast has since been echoed by swelling numbers of scientists who have added their own, increasingly urgent warnings about the ­dangers posed by our changing climate. I have been at pains to record these in the Observer – often to orchestrated choruses of hostile responses from climate-change deniers – and to make it clear that our addiction to fossil fuels is going to have dangerous consequences for our planet.
It remains the most striking ­scientific story that I have covered as the paper's science editor over the past 42 years, although I should also give credit to the multitude of other remarkable developments that have occurred in that period and which have been subjects of my reporting. These include our growing mastery of DNA science, the creation of mobile phones and computers, our improving ability to tackle the scourge of cancer, and the discovery that Homo sapiens have an African origin. I have listed highlights below this piece, and each demonstrates how dedicated researchers have transformed our understanding of our universe and our place in it since the 1980s.
Their impacts nevertheless look insignificant compared to the one that will occur if our interference with our planet's climate ­continues at its present rate. This is, quite ­simply, the greatest scientific experiment ever undertaken by humans. Our continually rising emissions of greenhouse gases are altering Earth – with our own species destined to be the prime test subject.
Melting ice caps, flooding coastal plains, droughts, severe storms and heatwaves threaten to displace ­hundreds of millions of people from their homelands as large chunks of our planet become ­uninhabitable. 'In such a future, we will bring about nothing less than the collapse of the living world – the very thing that our civilisation relies upon,' states Sir David Attenborough in A Life on our Planet.
Our scientific creativity and ingenuity could surely help us face down the coming devastation, it might be expected. We certainly have the intellectual capacity to halt the changes that lie ahead. Sadly, my experiences as science editor suggest otherwise – for just as I have watched breathtaking advances in science unfold, I have witnessed large parts of society turn their heads and deliberately reject the truths that have been presented to them. The rise of unreason has been the unwelcome partner to our growing scientific sophistication.
My first serious encounter with anti-science denial came with the arrival of Aids in the 80s. Scientists traced the cause: a virus now known as HIV which, they pointed out, is sexually transmitted. This point was disputed by many individuals who claimed it was caused by 'flawed' lifestyles and denied that Aids was caused by a virus. This was to have a devastating international impact after South Africa's president Thabo Mbeki asked several Aids deniers to join his presidential advisory panel on the disease. Widespread withholding of treatments for Aids ensued in South Africa, where the death toll from the disease reached hundreds of thousands of people.
An even more startling example is provided by Covid. Our understanding of the disease gradually changed after its appearance in late 2019, and advice was altered as scientists learned more about its causes. Washing hands was dropped as a mantra and staying outdoors became acceptable. This uncertainty was fed upon by social media.
Then came the vaccines, and the internet went into overdrive. Immunisation against Covid was linked to exaggerated numbers of deaths, and the subject was politicised, particularly in the US, where many Trump-supporting Republicans decided to shun the vaccine. The result was a grim distortion of responses to Covid infections in the US, with many fervently Republican counties showing significantly higher death rates compared with strong Democrat counties.
This affront to reason has continued. The US now has an outspoken vaccine sceptic as its health secretary while cases of measles, a disease once vanquished by vaccines, are returning in increasing numbers, along with reports of early deaths, as the influence of anti-vaxxers takes a grip of the country.
In the case of the climate ­crisis, denial has been long-lasting, pernicious and highly inaccurate. Claims that scientists have fiddled with facts have been shown to be unfounded while the warnings of climate experts, from John Mercer onwards, have proven highly accurate. As a result, we now stand at the threshold of a continuing rise in global temperatures – because deniers have been so effective in blocking progress towards the introduction of international agreements for limiting fossil fuel emissions.
Anti-science movements have always been with us, of course – from the rise of the flat Earthers to the early establishment of groups opposed to evolution. However, the present trajectory is now ­becoming extremely ­worrying, with the US providing the most ­worrying examples.
'It is undoubtedly political and connected with the rise of the right in the US,' says Sir Adrian Smith, president of the Royal Society. 'That is partly because Trump and many Republicans have a major down on elite universities in the US, and these are places where big science takes place.
'On the other hand, the recent rise of rightwing parties in European countries has not been mirrored with abuse of science, and so far the worst of this awfulness has not yet hit the UK. It is not something to take for granted over the coming years, however.'
DNA In 1982, when I joined the Observer, research into deoxyribonucleic acid, the material from which our genes are made, was in its infancy. Today we can sequence the entire genomes of individual men and women, revealing treasure troves of biological data that have revolutionised medical practice. Forensic science has also been transformed through the development of DNA fingerprinting while our understanding of our own evolution has been turned on its head by our ability to sequence DNA from tissue scraps left behind by our predecessors. Among the breakthroughs made this way has been the discovery that we once interbred with our extinct evolutionary cousins, the Neanderthals, and that their DNA makes up 1-2% of the genomes of people of European or Asian ancestry.
Gravitational waves were predicted by Albert Einstein, who nevertheless thought they could not be detected on Earth. He argued that these ripples in the space-time continuum – although generated by enormously energetic events – would be dissipated to a tiny fraction of their original magnitude by the time they reached Earth. Nevertheless, in 2015, researchers – in Louisiana and Washington – succeeded in detecting gravitational waves generated by the merger of two black holes by using giant laser interferometers that were capable of measuring wavelengths to an accuracy of a few hundred billion-billionths of a metre. This success has since opened up an entirely new way to study the universe.
The web When I started work as a reporter, we typed our stories on manual typewriters and, when out of the office, phoned in our stories to human copy takers. The creation of mobile phones, the internet and powerful personal computers has since transformed mass communication thanks to developments in a host of techniques including semiconductor nanotechnology, sensors, fiber optics, satellites and atomic clocks. Today, a mobile phone has a processing power and a memory capacity that are millions of times more powerful than the computer that guided the Apollo 11 mission to the moon.
Out of Africa Forty years ago, those who studied human origins were divided into two groups. One side argued that modern humans evolved separately from predecessors found in different areas round the globe. The other group said that Homo sapiens evolved in Africa before spreading out of the continent to take over the planet. The former theory was known as the multiregional hypothesis while the latter was called the Out of Africa theory. Detailed studies of fossils, ancient DNA and stone tools and other artefacts have since resolved the issue, and we now know the latter theory is correct. Essentially we are all Africans under the skin.
The James Webb space telescope Forty years ago, it was expected men and women would soon set up colonies on the moon and Mars. However, human spaceflight has since suffered financial setbacks and dwindling public interest. In contrast, the creation of sophisticated robot probes has transformed the study of the heavens, a trend that culminated in the 2021 launch of the world's most powerful observatory, the James Webb space telescope. It is now revealing the universe in unsurpassed detail with early results showing that the universe was already deep into the process of star formation only a short time after its big bang birth 13.8 billion years ago.