The Kyoto Protocol, which aims to slow global warming, finally came into force on 16th February, seven years after being agreed. 141 countries, responsible for about 55% of greenhouse gas emissions, have ratified the treaty, which pledges to reduce these emissions by 5.2% by 2012. However, the USA (which contributes over 25% of emissions) and Australia have abstained for selfish economic reasons, and developing countries such as China and India are excused.
Evidence that the Earth’s climate is changing rapidly is now overwhelming. The consequences of doing nothing will be bad for humans all over the world, for most other animals, and for the preservation of many endangered species of flora and fauna. A minority of people and animals are likely to be better off, but their gains will be outweighed by the losses of others. In Suffolk the first threat seems to come from rising sea levels that will destroy freshwater reed beds. Sites such as Minsmere, Walberswick marshes and Bawdsey are in danger and could easily be lost in one of the violent storms that will become increasingly frequent. Habitats of endangered species such as the bittern would be lost. In the case of prolonged droughts or long term changes in rainfall patterns species unable to adapt will perish. John Lanchberry of the Royal Society for the Protection of Birds said in February at the Exeter conference, Avoiding Dangerous Climate Change, wildlife is already being affected and that it will take very little further climate change to “catastrophically” affect other species. RSPB researchers had previously warned that 25% of land-based species have no future if temperatures rise as climate scientists predict.
Most of the people I meet fall into one of four categories in their attitude to climate change – ostriches, unbelievers, deckchair all-the-year-rounders and defeatists.
Those with their heads in the sand, and those in denial, leave me almost speechless, but I ask them whether they really believe that 30,000 climatologists and environmental scientists are conspiring to mislead, and anyway consider all the other benefits to be gained from cleaning up the atmosphere. There are many uncertainties but the risks of not taking immediate action are so great that they far outweigh the limited costs of taking action.
Deckchair hopefuls should note that there is no guarantee that temperatures will rise in Britain. If the Gulf Stream conveyer stops bathing our western shores with water from the tropics we could have a new ice age…
To the defeatists I say this – there are at least two ways you can make a difference.
One – cut down your personal contribution to greenhouse emissions. Leave your car at home, go on foot or cycle or use public transport or don’t make the journey. Leave the car journeys for those who really need them. Turn down the heating thermostat a couple of degrees, wear another layer, improve your loft insulation, use energy efficient light bulbs, and so on…
Two – make your voice heard.
There is a general election coming up, with opportunities to test the position
of the candidates and communicate your views. We need the government to set a
good example with more effective action on the home front, not missed targets.
We want much more pressure put on the US government. George W. Bush should be
shamed into signing up to the Kyoto principles. Romano Prodi, when he was
President of the Commission of the European Union put it nicely: “If one wants
to be a world leader, one must know how to look after the entire earth and not
only American industry”.
Climate change will be the theme for the SNS 2005 conference.
The Hadley Centre is the UK Government’s centre for research into climate change science. It is part of the Met Office, located within its new Exeter headquarters.
The information below is taken from the booklet Stabilising climate to avoid dangerous climate change – a summary of relevant research at the Hadley Centre (January 2005). The full report can be obtained from www.metoffice.gov.uk as a pdf document or in paper format from Met Office, Hadley Centre, FitzRoy Road, Exeter, EX1 3PB.
In the extracts below, “model” means computerised climate models to simulate climate change, built on the Met Office NEC supercomputer at the Hadley Centre.
“What constitutes ‘dangerous’ climate change, in the context of the UN Framework Convention on Climate Change, remains open to debate.”
“The inertia of the climate system means that we could be committed to dangerous change, many decades before we reach the dangerous level.”
“This booklet does not attempt to come up with an answer…”
Changes to the Gulf Stream
“Large currents in the ocean transport vast amounts of heat between the equator and higher latitudes… In the North Atlantic there are two areas – one in the Labrador Sea and the other between Greenland, Iceland and Norway – where the ocean surface is cooled by cold winds, becomes more dense, and then sinks. The cool water flows at depth towards the equator… and is replaced by warm water flowing from the Gulf of Mexico… called the Gulf Stream.
“However, this sinking process can be disrupted when fresh water from rain, rivers or melting ice overlays the salty ocean water. An increase in fresh water could slow down or even switch off the Gulf Stream. A ‘what-if’ experiment using the Hadley Centre computer model shows that if it did [switch off], the UK annual temperature would cool by up to 5ºC in a matter of a decade or two. But the effect on extreme temperatures would be worse… winter daily minimum temperatures in central England could regularly fall well below minus10ºC or so.
“[In another projection] The model projects that the Gulf Stream would slow down by about 20% by the middle of the century, but by no means completely switch off [even if emissions were at the high end of the projected range]…The same model also predicts that one of the sinking areas, in the Labrador Sea, ceases to operate by about 2020…[this] might be thought a large enough change in the physical climate system to be regarded as dangerous. However, the cooling effect on Europe was more than offset by the greenhouse-effect warming…”
“…there is no single robust calculation, reflecting our lack of understanding of ocean currents and their apparent stability. Some recent measurements from research ships in the Arctic seem to indicate that changes are already taking place.”
“About half of the carbon dioxide emitted by fossil fuel burning is absorbed by natural ‘sinks’ in ecosystems and oceans…there are concerns that this free service provided by nature may run out in the future, as natural sinks weaken due to climate change.
“As CO2 and temperatures rise due to man’s activities, several things happen. Firstly, extra CO2 acts as a fertiliser and increases the growth of vegetation – particularly in northern forests where warming also encourages growth – and this helps to offset man’s emissions (although new tree growth may darken the surface and act to warm the planet). But in some parts of the world, where rainfall decreases and higher temperatures increase evaporation, vegetation will die back.
“Thus, instead of carbon being drawn from the atmosphere, it will actually return to the atmosphere to enhance already increasing concentrations. The same thing happens in much greater quantities and on a global scale in soils, as microbial activity is accelerated in a warmer climate and more carbon dioxide is emitted.
…[the model shows] the strength of the vegetation sink starts to diminish in the latter half of this century, and by the final decades turns into a net source. Soils change even more quickly, and are predicted to become an additional source of carbon by the middle of the century.
…The ocean also plays a large part in the carbon cycle. It provides a ‘chemical sink’ for carbon dioxide simply by absorbing more of it. It also provides a ‘biological sink’ as carbon is absorbed by phytoplankton and higher life forms… a warmer ocean can absorb less CO2 and, as surface waters saturate, the ocean carbon sink will weaken if the circulation does not transport the carbon to depth… the net effect is predicted to be a reduction in uptake… due to climate change, leaving more CO2 in the atmosphere.”
“The Greenland ice sheet is more than three kilometres thick in places and contains nearly three million cubic kilometres of ice. If it were to melt, sea levels around the world would rise by about seven metres, inundating many coastlines and most of the world’s major cities. The Intergovernmental Panel on Climate Change estimated that the ice sheet would begin to contract once [global warming] reaches about 1.5ºC – and a complete meltdown, taking millennia, would be inevitable…”
“Methane hydrates …are structures consisting of frozen methane… found in areas of the ocean which are sufficiently cold and at sufficiently high pressure to keep them stable – that is, at the floor of deep cold oceans… it is estimated that…[the carbon] locked up in methane hydrates [is] twice as much as in coal, oil and natural gas reserves. If ocean warming penetrated sufficiently deeply… it could lead to a rapid increase in greenhouse warming… Work continues to refine the calculations…”
“Work using an initial 53 models shows that the level at which CO2 would need to be stabilised in order to limit global-mean temperature rise to 2ºC above the present day, would need to be in the range of about 490 to 670ppm (5% and 95% confidence levels)…”
1. Readers should note that in selecting these quotations I have tried not to distort the general drift of the paper. However, the full document is 16 pages long and should be read in its entirety to get the full picture. In places the meaning is rather obscure and I have attempted to clarify with my own words ( in square brackets).
2. CO2 concentrations (ppm) derived from in situ air samples collected over the past 50 years by Mauna Loa Observatory, Hawaii can obtained on the following website: http://cdiac.esd.ornl.gov/by_new/bysubjec.html#atmospheric
The December 2003 value is approximately 376ppm cf 316ppm for 1959, an increase of 18.8%.
Jenkins, G. et al 2005 Stabilising climate to avoid dangerous climate change. The Met Office. Exeter, UK
© 2005 Suffolk Naturalists' Society
used by kind permision.