will rise by over six degrees. To put that into perspective, a rapid six-degree temperature increase is what some scientists believe to have brought about the mass extinction that marked the end of the Permian period some 250 million years ago. That six-degree increase is estimated to have taken some 10,000 years to occur and it took life on Earth tens of millions of years to recover from that catastrophic episode of global warming. Back then the climate change was probably caused by volcanic activity: this time the warming is caused by power stations, deforestation, cars, farms, and factories. If we don’t do something about these sources of global-warming gases very quickly, then we could, the most recent projections show, trigger six degrees of warming not over 10,000 years, but in less than a century.
Temperatures even three degrees above the
pre–industrial average have not been seen
since the Pliocene period, some three million
years ago. At that time sea levels were up
to 25 metres higher than now.
At the moment this appears to be where we are heading. Emissions scenarios prepared in 2000 set out different possible future emissions levels based on different assumptions about economic growth and the uptake of new technology. And yet in 2005, 2006 and 2007 the world’s emissions of greenhouse gases were above the line set out in the worst-case scenario. We have arrived at the brink of potential disaster, and yet we still accelerate towards the edge.
Glaciers are very sensitive to climate change and as the average global temperature rises glacier retreat is underway worldwide. At Glacier Bay National Park, Alaska, there has been dramatic glacier shrinkage. On the left a steamship sails toward the Muir Glacier in 1902. From the same viewpoint in 2005 the glacier has disappeared.
Nevertheless there is some cause to be encouraged. We still have some time to minimize the impact of the increases in carbon-dioxide levels, but not much. For the industrialized developed countries, a cut in carbon-dioxide pollution of about 40 per cent by 2020 might place the world on an emissions reductions path that could avoid the worst effects of what lies ahead. That is not to say that the impact we have on the world could or must be reduced to zero by then, but rather that this is the direction we should be travelling in. What is certain is that this is mostly the opposite direction to that travelled by humanity today.
The evidence which shows Man-made impact on the climate system recently became the subject of fierce debate. Those who are sceptical that humanity’s activities have caused climate change made an all-out assault on the evidence base in the run-up to the UN Conference on Climate Change in Copenhagen at which I spoke. The row had an alarming effect on public opinion, and being so close to it I could see that it was a deliberate attempt to dampen the justified concerns about the climate change threat that the Media had been increasingly reporting in recent years. But whether you choose to believe the sceptics rather than the vast body of evidence that now exists, climate change is not the only large-scale ecological challenge that we face. Alongside changes to our planet’s atmosphere, the activities of our single species have caused an unprecedented assault on the fabric of life.
Depletion
Modern scientific investigation tells us that today we sit at the pinnacle of some 3.5 billion years of evolutionary refinement. It seems to me that the interdependent web of connections, relationships and flows of energy, the finely woven tapestry of life, is undoubtedly the greatest marvel ever placed before us.
It is not necessary to travel to the tropical rainforests or to dive among tropical coral reefs to be at the cutting edge of our knowledge of life on Earth. In 2008 a scientist working at the Natural History Museum in London was presented with what turned out to be possibly a ‘new’ species of bug. It was picked up by his son while eating his lunch in the museum’s central London gardens. The almond-shaped insect, about the size of a grain of rice, had made itself at home in the sycamore trees in the nineteenth-century museum’s grounds. About a mile away at Buckingham Palace, two species of mushroom, apparently new to science, were recently found in the gardens.
I have for many years been privileged to spend time speaking with and learning from some of the world’s leading experts on the natural world. Today they have a new name for this tremendous variety of life: it’s called biodiversity. The most incredible fact about the multiplicity of forms of life and the myriad associations they all form is the amazing variety. The most alarming is the rate at which it is disappearing. There are many stories that underline the urgency we face in stemming the tide of biodiversity loss that is taking place all around us. One that is close to my heart begins high on a hill in New Zealand.
Taiaroa Head is at the northerly tip of the Otago Peninsula, overlooking the entrance to Otago Harbour, at the head of which is the town of Dunedin. Here in Spring it is possible to watch at close quarters one of the most remarkable of all birds: the albatross – more specifically the Northern Royal albatross. The birds that nest here each year make up the only mainland albatross colony in the world. All the others are on small islands, with many located on some of the world’s most inaccessible oceanic outposts.
The albatrosses that breed at Taiaroa are enormous creatures. White, with great long black wings, they are surely the most majestic of birds. They nest in peace because they have the full protection of New Zealand law. They are a major tourist attraction and have made Dunedin world-famous. But when they have reared their single chick and set out to sea once more, they face great peril. For millions of years albatrosses have wandered the oceans as masters of wave and wind. Twenty-four kinds of these great birds hunted and roamed in a watery world apparently without limit. During my time sailing the high seas when I served with the Royal Navy nearly forty years ago, I watched these birds, marvelling at the vastness of their world and the way they were perfectly adapted to the conditions that enabled them to thrive in what for us humans are such hostile conditions. But even this great ocean wilderness is no longer the sanctuary it was for these mariners of the remotest seas. No fewer than twentyone species of the twenty-four are now regarded as being in danger of extinction.
The Taiaroa Head Royal Albatross colony at Dunedin in New Zealand is an unforgettable place to visit. This six week old chick is doing well.
This young Laysan Albatross died after being repeatedly fed with plastic debris collected from the sea by its parents.
This is because it is not only albatrosses that seek a living from the vast and seemingly empty oceans that ring Antarctica. Thousands of miles from their home ports, long-line fishing boats also patrol these wild seas. They come after large predatory fish and catch them with hooks trailed out on lines up to an astonishing eighty miles long carrying tens of thousands of small squid for bait – exactly the food of albatrosses. The hooked lines aim to catch valuable species such as toothfish, tuna and swordfish, but the baits are also lethal for albatrosses.
The birds dive onto the baited hooks and the sharp barbs slice into their beak or throat. A vain struggle is soon followed by a painful death by blood loss or drowning. It is an unglamorous end for birds
