Has global warming stopped?

'The global temperature of 2007 is statistically the same as 2006 and every year since"

'The fact is that the global temperature of 2007 is statistically the same as 2006 and every year since 2001'. Plus read Mark Lynas's response

Global warming stopped? Surely not. What heresy is this? Haven’t we been told that the science of global warming is settled beyond doubt and that all that’s left to the so-called sceptics is the odd errant glacier that refuses to melt?

Aren’t we told that if we don’t act now rising temperatures will render most of the surface of the Earth uninhabitable within our lifetimes? But as we digest these apocalyptic comments, read the recent IPCC’s Synthesis report that says climate change could become irreversible. Witness the drama at Bali as news emerges that something is not quite right in the global warming camp.

With only few days remaining in 2007, the indications are the global temperature for this year is the same as that for 2006 – there has been no warming over the 12 months.

But is this just a blip in the ever upward trend you may ask? No.

The fact is that the global temperature of 2007 is statistically the same as 2006 as well as every year since 2001. Global warming has, temporarily or permanently, ceased. Temperatures across the world are not increasing as they should according to the fundamental theory behind global warming – the greenhouse effect. Something else is happening and it is vital that we find out what or else we may spend hundreds of billions of pounds needlessly.

In principle the greenhouse effect is simple. Gases like carbon dioxide present in the atmosphere absorb outgoing infrared radiation from the earth’s surface causing some heat to be retained.

Consequently an increase in the atmospheric concentration of greenhouse gases from human activities such as burning fossil fuels leads to an enhanced greenhouse effect. Thus the world warms, the climate changes and we are in trouble.

The evidence for this hypothesis is the well established physics of the greenhouse effect itself and the correlation of increasing global carbon dioxide concentration with rising global temperature. Carbon dioxide is clearly increasing in the Earth’s atmosphere. It’s a straight line upward. It is currently about 390 parts per million. Pre-industrial levels were about 285 ppm. Since 1960 when accurate annual measurements became more reliable it has increased steadily from about 315 ppm. If the greenhouse effect is working as we think then the Earth’s temperature will rise as the carbon dioxide levels increase.

But here it starts getting messy and, perhaps, a little inconvenient for some. Looking at the global temperatures as used by the US National Oceanic and Atmospheric Administration, the UK’s Met Office and the IPCC (and indeed Al Gore) it’s apparent that there has been a sharp rise since about 1980.

The period 1980-98 was one of rapid warming – a temperature increase of about 0.5 degrees C (CO2 rose from 340ppm to 370ppm). But since then the global temperature has been flat (whilst the CO2 has relentlessly risen from 370ppm to 380ppm). This means that the global temperature today is about 0.3 deg less than it would have been had the rapid increase continued.

For the past decade the world has not warmed. Global warming has stopped. It’s not a viewpoint or a sceptic’s inaccuracy. It’s an observational fact. Clearly the world of the past 30 years is warmer than the previous decades and there is abundant evidence (in the northern hemisphere at least) that the world is responding to those elevated temperatures. But the evidence shows that global warming as such has ceased.

The explanation for the standstill has been attributed to aerosols in the atmosphere produced as a by-product of greenhouse gas emission and volcanic activity. They would have the effect of reflecting some of the incidental sunlight into space thereby reducing the greenhouse effect. Such an explanation was proposed to account for the global cooling observed between 1940 and 1978.

But things cannot be that simple. The fact that the global temperature has remained unchanged for a decade requires that the quantity of reflecting aerosols dumped put in our atmosphere must be increasing year on year at precisely the exact rate needed to offset the accumulating carbon dioxide that wants to drive the temperature higher. This precise balance seems highly unlikely. Other explanations have been proposed such as the ocean cooling effect of the Interdecadal Pacific Oscillation or the Atlantic Multidecadal Oscillation.

But they are also difficult to adjust so that they exactly compensate for the increasing upward temperature drag of rising CO2. So we are led to the conclusion that either the hypothesis of carbon dioxide induced global warming holds but its effects are being modified in what seems to be an improbable though not impossible way, or, and this really is heresy according to some, the working hypothesis does not stand the test of data.

It was a pity that the delegates at Bali didn’t discuss this or that the recent IPCC Synthesis report did not look in more detail at this recent warming standstill. Had it not occurred, or if the flatlining of temperature had occurred just five years earlier we would have no talk of global warming and perhaps, as happened in the 1970’s, we would fear a new Ice Age! Scientists and politicians talk of future projected temperature increases. But if the world has stopped warming what use these projections then?

Some media commentators say that the science of global warming is now beyond doubt and those who advocate alternative approaches or indeed modifications to the carbon dioxide greenhouse warming effect had lost the scientific argument. Not so.

Certainly the working hypothesis of CO2 induced global warming is a good one that stands on good physical principles but let us not pretend our understanding extends too far or that the working hypothesis is a sufficient explanation for what is going on.

I have heard it said, by scientists, journalists and politicians, that the time for argument is over and that further scientific debate only causes delay in action. But the wish to know exactly what is going on is independent of politics and scientists must never bend their desire for knowledge to any political cause, however noble.

The science is fascinating, the ramifications profound, but we are fools if we think we have a sufficient understanding of such a complicated system as the Earth’s atmosphere’s interaction with sunlight to decide. We know far less than many think we do or would like you to think we do. We must explain why global warming has stopped.

David Whitehosue was BBC Science Correspondent 1988–1998, Science Editor BBC News Online 1998–2006 and the 2004 European Internet Journalist of the Year. He has a doctorate in astrophysics and is the author of The Sun: A Biography (John Wiley, 2005).] His website is www.davidwhitehouse.com

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Puffins in peril

Britain’s best-loved seabird is vulnerable to global extinction.

The boatmen helped us scramble ashore and soon there were 50 people wandering on an uninhab­ited slab of sea-battered dolerite called Staple Island. It is one of the National Trust-owned Farne Islands in Northumberland and among England’s most spectacular wildlife locations. There are 100,000 pairs of breeding seabirds here and they were everywhere: at our feet, overhead, across every rock face. The stench of guano was overwhelming.

While the birds seemed to be boundless, the human beings converged on the grassy knoll where the local star attraction resides. It’s the creature that adorns the boat company’s publicity and is emblazoned on the National Trust’s website for the island, the bird that possesses what the poet Norman MacCaig called the “mad, clever clown’s beak”: the pint-sized, parrot-faced puffin.

The British love for this creature is so intense that it is, in essence, the robin redbreast of the sea. Nearly all of its breeding colonies around our coast are tourist attractions. Just across the water, along the shore from Staple Island, is the town of Amble, which holds an annual festival devoted to the puffin. From Lundy in Devon and Skomer in Pembrokeshire to the Isle of May off the Fife coast, or Fair Isle in the Shetlands, trips to puffin colonies are frequent, sometimes daily, events.

“Every tourist shop on these islands sells puffin merchandise – knitwear patterns, tumblers, carvings, coasters, cuddly toys, clothes and, of course, puffin hats,” Helen Moncrieff, the area manager in Shetland for the Royal Society for the Protection of Birds (RSPB), told me.

While the love affair is unquestionable, what seems in doubt is our ability to help the bird now that it is in trouble. Fair Isle once supported a puffin colony of 20,000 birds. In less than three decades, that number has halved. Similar declines have been reported at Britain’s most important puffin site on St Kilda, Scotland, where millions are said to have bred. Now there are fewer than 130,000 pairs, half the total recorded as recently as the 1970s.

The national picture is alarming but the news from elsewhere is even worse. Continental Europe holds more than 90 per cent – five million pairs – of the global total of Atlantic puffins but they are shared primarily between three countries: Denmark (the Faroe Islands), Iceland and Norway. Across this subarctic region, losses have been estimated at 33 per cent since 1979, when monitoring began. But the most striking figure comes from a colony on Røst, Norway, where there has been a fall over this period from nearly 1.5 million pairs to 285,000.

The Westman Islands off the south coast of Iceland hold a substantial proportion of the country’s puffins. Since 2005, breeding success there has been almost nil, and a similar failure has recurred on the Faroe Islands for more than a decade. In both places, where hunting puffins was once a staple of cultural life, catchers today have initiated a self-imposed moratorium.

Puffins are long-lived species and a life­span of between 20 and 30 years is not unusual, yet Euan Dunn, principal marine adviser to the RSPB, explains the implications of persistent breeding failure. “Puffins on Shetland or the Westmans may go on attempting to breed for years, even decades, but eventually all those old adult birds will die off and, if they haven’t reproduced, then the numbers will start to plunge.”

BirdLife International, a conservation network that classifies the status of birds worldwide, has reached the same conclusion. It judges that the Atlantic puffin is likely to decline by between 50 and 79 per cent by 2065. The nation’s most beloved seabird has been declared a species that is vulnerable to global extinction.

To unpick the story of puffin losses, marine ecologists have examined the bird’s oceanic ecosystem and looked particularly at changes in the status of a cold-water zooplankton called Calanus finmarchicus. This seemingly insignificant, shrimp-like organism plays a crucial role in North Atlantic biodiversity and has experienced a huge decline as sea temperatures have risen steadily since the 1980s. While the decline of the finmarchicus coincided with swelling numbers of a close relative, this other zooplankton species is less abundant and nutritious.

As the finmarchicus has suffered, so, too, has one of its main predators, the lesser sand eel. And it is this formerly superabundant fish that is the staple food of puffins in many areas of the Atlantic. At the root of the disruption to marine life are the hydra-headed effects of climate change.

Though no one disputes that an important shift is under way in the sea areas of northern Britain and beyond, not everyone agrees that the present puffin situation is a crisis. A leading British expert, Mike Harris, thinks it is premature to designate the bird an endangered species. There are still millions of puffins and, he says, “We need numbers to plummet before we even start to assume that things are terminal.”

Similarly, Bergur Olsen, one of the foremost biologists studying puffins in the Faroe Islands, believes that the talk of extinction is over the top. “The food situation may change and puffins may well adapt to new prey, and then their numbers will stabilise and perhaps increase,” he says.

***

On Staple Island, the extinction designation does appear bizarre. The Farne Island puffin population has increased by 8 per cent since 2008 and there are now 40,000 pairs. This success mirrors a wider stability among puffin colonies of the North and Irish Seas. The distinction in feeding ecology which may explain the birds’ varying fortunes is that, in the southern parts of the range, puffins can prey on sprats when sand eels are scarce. Sprats appear to have suffered none of the disruption that assails the other fish.

But Dunn says it is important to look at the whole picture. “It’s fantastic that puffins are doing well in places like the Farnes, but remember: Britain holds less than 10 per cent of the world total. Also, the declines that have beset puffins in Shetland and St Kilda are even worse for other seabirds.”

The numbers of a silver-winged gull called the kittiwake have fallen by 90 per cent in Shetland and St Kilda since 2000 and by 80 per cent in the Orkneys in just ten years. Shetland’s guillemot numbers have also halved, and the shag, a relative of the cormorant, has experienced falls of over 80 per cent on many islands since the 1970s – 98 per cent, on Foula. Most troubling is the fate of the Arctic skua, which feeds mainly on fish it steals from other seabirds and is reliant on their successes. Its declines are so severe that Dunn fears its eventual loss as a breeding species in Britain.

While there is disagreement about what to call the puffin predicament, there is unanimity on one issue: much of the data that informs the discussion in Britain is out of date. All of these seabirds, which are of global importance, have been monitored decade by decade since the 1970s. Yet the most recent big audit of our cliffs and offshore islands was concluded in 2000. The full census data is now 16 years old. The organisation that underwrites this work is the Joint Nature Conservation Committee; it is sponsored by the Department for Environment, Food and Rural Affairs, which has suffered deep budget cuts since the 2008 financial crisis. There is no certainty that another comprehensive census will be mounted any time soon.

“Much is made on wildlife television of how special these islands are for wildlife and how much we care about it,” Dunn says. “In the case of our seabirds, one of those claims is indisputably true. Britain holds populations of some species that are of worldwide significance. But if we lack even basic information on those birds and how they’re faring, especially at a time when our seas are in such flux, what message does that send about how much this country cares? And how can we ever act effectively?”

The plight of the puffin is shedding light on the fortunes of our marine wildlife generally and the shifting condition of our oceans as a result of rising carbon-dioxide levels. Now, puffin politics is also starting to show
this government’s indifference to nature.

This article first appeared in the 28 July 2016 issue of the New Statesman, Summer Double Issue