|
EARTH CONSUMING TOO MUCH This month (June 2001), the Worldwatch Institute released its annual "statistical snapshot" of the world's economic trends and their environmental consequences. This year the institute was joined by the United Nations Environment Program (UNEP) to compile Vital Signs 2001: The Trends That Are Shaping Our Future. Based on the new report, the average temperature of the atmosphere at the Earth's surface held steady at 14.36°C, making the past two years the sixth and seventh warmest on record. An older NASA dataset using only meteorological stations, dating back to 1867, has 2000 listed as the ninth warmest year on record. However, not everything is bad news. Global carbon emissions from fossil fuel combustion declined for the third year, by 0.6% to just below 6.3 billion metric tons. In addition, the amount of carbon emitted per unit of global economic output continued to fall, by 3.6%, to 148 metric tons of carbon per million dollars of gross world product. The report attributed part of these gains to the 33.2% reductions of greenhouse gases (GHG) emissions made by former Eastern Bloc nations since 1990. Nevertheless, western industrialised nations have increased carbon emission by 9.2% since 1990. The US, which is responsible for 24% of the world's GHG emissions, is emitting 13% more than in 1990. The EU and Japan are also falling short of their reduction targets. According to Klaus Töpfer, UNEP's executive director: "The challenge of this new century is to extend the economic progress of the last 50 years, while halting the ecological decline - a sick planet will, sooner or later, lead to a faltering economy." Source: Global Environmental Change Report, 22nd June 2001.
A new study conducted by the Wildlife conservation Society (CWS), suggests that coral bleaching, in which reef-building corals lose symbiotic algae and become white during times of stress, may actually help some corals adapt to global warming and other environmental changes. Andrew Baker, of WCS's Osborn Laboratories of Marine Sciences, transplanted eight species of sleractinian (stony) corals found in Panama's San Blas archipelago from shallow water (2-4 m) to deep water (20-23 m), and vice versa. The outcome was that corals in the shallow water bleached after eight weeks, but ultimately survived by recovering with new algae. Corals transplanted to the colder water did not bleach but poorly adapted, and many of these eventually died. The study challenges the conventional view that coral bleaching is necessarily detrimental. "These findings indicate that bleaching can sometimes help corals respond quickly to environmental change," said Baker. "The same bleaching that makes corals so fragile may also during times of extreme environmental stress, help some of them survive. That adaptation measure may be key to the survival of some ecosystems as sea surface temperature rise. Nevertheless, Baker noted that bleaching, particularly as a result of warmer sea temperatures, is still a major cause for concern, and will likely continue to cause high mortality among reef ecosystems. Source: Global Environmental Change Report, 22nd June 2001; Nature, 14 June 2001, vol. 411, pp. 765-766.
The Climate Change Projects Office (CCPO) is a new climate change bureau, which will be launched by the UK Government to encourage UK business to invest in efforts to cut greenhouse gas emissions overseas. The CCPO will provide advice and support for businesses interested in carrying out projects under two 'Kyoto mechanisms', Joint Implementation and the Clean Development Mechanism. It will be guided by a steering committee chaired by Nick Baldwin, Powergen's chief executive. A draft framework for the Emissions Trading Scheme - a measure that could cut carbon by at least two million tonnes a year by 2010 - due to start in April 2002, is published this month (May 2001). The Government has pledged £43m in 2003-04, to be allocated through a bidding system, as a financial incentive for companies to join the scheme. Most questionnaires returned by companies and business highlighted the need for simplicity, flexibility, periodic review, and broad participation, and most agreed that all greenhouse gases should be included within the scheme as soon as possible. Many stressed that taking time to get the scheme right was more important than an early start. Source: DETR Press Release. END OF THE ROAD FOR KYOTO PROTOCOL?George W. Bush, the President of the Unties States of America, last month decided to pull his country out of the Kyoto Protocol, the international agreement to reduce emissions of greenhouse gases, which threaten global warming. The Kyoto Protocol required the US to reduce its 1990-level greenhouse gas emissions by 7% by the period 2008-2012. Bush's decision, whilst criticised around the world by other Parties to the Protocol, has been welcomed back home by many business groups, including the coal and oil industries. The Global Climate Coalition (GCC), which represents a number of corporate interests in the climate debate, also praised the new position, not so much for pulling out of the Kyoto Protocol but because the Bush administration, like the GCC, supports market-based solutions and new technologies to address climate change. Despite this, a CNN-Time poll conducted at the end of March reveals that as many as three-quarters of the US public believe that global warming is a serious problem, whilst two-thirds think that the president should develop greenhouse gas emission reduction strategies. The problem facing the Kyoto Protocol now is whether it can survive without the Americans on board. The Protocol will become legally binding once 55 Parties (nations) have ratified it, including industrialised nations that account for at least 55% of carbon dioxide emissions. Since the US alone accounts for 34% of all industrialised nations' carbon dioxide emissions, a workable policy without the US may now seem unlikely. Despite this, other countries, particularly within the European Union, have stressed that the Kyoto Protocol can survive without the US. In addition, the environmental group Greenpeace issued a statement in which it said the United States was "isolated in the world in its rejection of the Protocol." The next round of international talks on climate change will take place in Bonn in July later this year. Source: Global Environmental Change Report, 13th April 2001.
The 15 European Union (EU) countries recorded a 4% reduction between 1990 and 1999 in combined emissions of the six greenhouse gases covered by the Kyoto Protocol on climate change. This contrasts with an 11% increase in emissions over the same period in the United States - which accounts for over a third of the industrialised world's man-made emissions. The figures come from the latest emissions inventory produced by the European Environment Agency (EEA), in which it also warns against complacency, saying that further efforts to reduce emissions are needed to achieve the Kyoto targets. The cut takes the EU - responsible for a quarter of industrialised countries' man-made emissions of the six gases - half way towards achieving the Kyoto target. The inventory also shows that the EU remains on track to meet its commitment to stabilise emissions of carbon dioxide, the most important greenhouse gas, at the 1990 level by the year 2000. The favourable picture to date is largely due to considerable emissions falls in Germany and the United Kingdom, the EU's two biggest emitters, which together contribute around 40% of total EU greenhouse gas emissions. However, the situation could rapidly change, the EEA has warned. Preliminary estimates indicate that in 2000 both UK and German carbon dioxide emissions increased and on present trends, more than half of the other Member States may substantially exceed their agreed share of the EU's total allowed emissions under the Kyoto Protocol. Source: EU Business, 23rd April 2001, EU greenhouse gas emissions down 4%.
Reporting in the journal Nature, (vol. 410) scientists from Imperial College London have revealed further direct evidence of an increase in the Earth's natural greenhouse effect between 1979 and 1997. By analysing variations in the spectrum of outgoing infrared radiation collected by orbiting spacecraft in the early 1970s and during 1996-1997, the researchers were able to detect changes in the effect of greenhouse gases on temperature. The apparent change in the amount of energy emitted by the Earth is consistent with increases in atmospheric greenhouse gas concentrations over the same time period. Source: Global Environmental Change Report, 23rd March 2001.
According to the IPCC Climate Change Report released in January 2001 (see latest IPCC Climate Projections), climate change could have dramatic consequences for the Arctic this century. Scientists have not ruled out the possibility that the entire Arctic could become ice-free. If the amount of atmospheric carbon dioxide reaches twice its pre-industrial levels, the report says, then the summer sea ice in the Arctic could shrink by up to 60%. This could happen by as early as 2050, nearer to us now than the end of the Second World War. The extent of the Arctic sea ice has declined by almost a third in the past 130 years, and the report says it is possible that the Arctic could lose all its ice. Considerable ice sheet melting is also expected to occur on Greenland. Additionally, there is concern about the permafrost, the layer of permanently frozen soil which serves as the solid foundation for buildings and other structures throughout the Arctic. Melting permafrost in Siberia has already weakened buildings in several cities. Furthermore, the Arctic permafrost stores a lot of carbon dioxide and methane, which if released through melting, will cause a positive feedback adding to the warming process. Source: BBC News online, 19th February 2001, Global warming 'could melt Arctic'.
In February 2001 the UK Department of Health published the first official report into the possible health effects of climate change. The report identifies environmental factors that could affect the health of the population and will assist the Government's long term planning on issues of climate change and health in the UK. The report was produced by the Expert Group on Climate Change and Health, including experts from the meteorological and climate changes fields, as well as from physiology, public health, epidemiology and microbiology. The Health Effects of Climate Change report is being published as a scientific review for comment. While accepting the difficulties of predicting the impact of climate change on the health of the UK population, the report concludes that climate change will have a significant effect on health in the UK. However, not all the effects will be negative. The report suggests that the National Health Service should cope well with the impact of climate change, given adequate planning and resources, and concludes that early action may mitigate many of the possible consequential health effects of change. Some of the key predictions include:
Source: The Times newspaper online, 10th February 2001; UK Department of Health Press Release, 9th February 20011.
Although the Government has committed itself to reducing emissions of carbon dioxide, the main greenhouse gas, to 20% below their 1990 levels by 2010, the UK is likely to miss its internationally agreed targets for reducing the greenhouse gases which cause global warming, according to a report published by Cambridge Econometrics, the independent energy analysts. Instead, carbon dioxide emissions will increase over the next decade and in 2010 will be only 6.5% lower than in 1990. The report singles out road users and households as the main culprits. Thanks to the so-called dash for gas during the 1990s, emissions from power stations are falling and in 2010 are expected to be 23% lower than in 1990, while more efficient use of energy will allow industry to cut emissions by more than 15%. But households and car owners will have to become more energy efficient as well if the UK is to meet the targets it agreed at the Kyoto climate change talks in 1997. UN scientists believe that the world's average temperature will rise by 6ºC by 2100 (see "Latest IPCC Climate Projections"), even after implementation of the Kyoto Protocol targets, which many countries have yet to sign up to. Source: Guardian newspaper online, 5th February 2001
In January 2001, the United Nations Intergovernmental Panel on Climate Change (IPCC) released a draft report of the Third Assessment Report of Working Group I that builds upon past assessments and incorporates new results from the past five years of research on climate change. In the report the IPCC confirms that Earth's average surface temperature could rise by almost 6ºC by 2100 - a rise unprecedented in the past 10,000 years. At the same time sea levels could rise by almost a metre. Whilst the IPCC recognise that natural factors alone can influence the global climate, the warming over the past 100 years is very unlikely to be due to internal variability alone, but to predominantly man-made greenhouse gas pollution. According to the report, the 1990s was the warmest decade for 1,000 years. Temperatures rose by an average of 0.6ºC during the last century, with an increase in floods and droughts. Carbon dioxide levels in the atmosphere have risen by 31% since the beginning of the Industrial Revolution, largely as a result of the burning of fossil fuels. The draft of the Third Assessment Report of the IPCC WGI can be dowloaded from: http://www.ipcc.ch Source: Intergovernmental Panel on Climate Change Shanghai Draft WGI Third Assessment Report; Guardian newspaper online, 23rd January 2001.
England and Wales have experienced the wettest autumn since records began in 1766. The total rainfall in England and Wales during the September to November period was nearly 500mm, well surpassing the previous record of 456mm set in 1852. Further rainfall has been forecast for the remaining days in September. According to the Meteorological Office wet autumns were likely to become a regular feature of British weather as a result of climate change, although rainfall throughout the year will be relatively unchanged since summers are expected to become drier, particularly in the south east. The record-breaking rainfall has been the result of frequent slow moving low-pressure systems from the Atlantic. Although not evidence for global warming on its own, this autumn's unseasonable weather could be expected to occur more frequently if global temperature continues to rise as a result of man-made greenhouse gas pollution. Source: BBC News Online, 27th November 2000.
In November the Environment Minister, Michael Meacher, launched the new UK Climate Change Programme. The UK is one of the few developed countries to have published a clear strategy for delivering its 12.5% reduction target under the Kyoto Protocol, aimed at reducing greenhouse gas emissions. The new UK Climate Change Programme includes policies that could cut the UK's greenhouse gas emissions by 23% below 1990 levels in 2010 - almost double our legally-binding target - while acknowledging that cuts of up to 60-70% globally may be necessary in the long term. Cuts of 19% in carbon dioxide emissions could be achieved, with further action delivering the domestic 20% goal. The new Programme focuses on the challenge of preparing to make bigger emission cuts by ensuring a fundamental shift in the way we generate and use energy over the coming century. It announces that the Government plans a national debate on how the UK can make the transformation to a low carbon economy and that it will be reviewing the options for future energy choices. The UK Climate Change Programme is available on the Internet. Source: DETR Press Release, 17th November, Meacher sets pace for international climate change talks (UK Climate Change Programme launched).
Signatory nations to the 1992 Framework Convention on Climate Change assembled in the Hague, Netherlands, in November at the 6th Conference of Parties (COP6) to discuss the implementation of the Kyoto Protocol, which aims to reduce global greenhouse gas emissions by 5.2% by 2008 to 2012. Despite initial optimism that the Hague Conference would be another environmental landmark, the talks failed to produce concrete agreements amongst nations about how greenhouse gas emissions should actually be reduced in practice. The main stumbling block came over the issue of whether and how "flexible mechanisms" like carbon sinks and emissions trading should be accommodated into national reduction strategies. The United States, along with its allies in the bloc known as the Umbrella Group - which includes Australia, Canada, Iceland, Japan, New Zealand, Norway, Russia and the Ukraine - has argued that "flexible mechanisms" can help countries meet their domestic emission reduction targets without threatening economic growth. The European Union, however, has opposed the inclusion of carbon sinks such as new forests, on the grounds that it allows polluters to circumnavigate their responsibility for actually cutting real emissions, and as such goes against the spirit of the Kyoto Protocol. Further information about COP6 can be found at the Conference website. Source: Global Environmental Change Report, 24th November 2000.
New results from the latest Hadley Centre climate change computer model published in Nature (vol. 408, pp 184-190) suggest that the global average surface temperature could rise by 8ºC by the end of the 21st century. For the first time, scientists have modelled the effects of climatic-induced change in vegetation, soils and oceans, thereby representing more realistically the Earth's coupled climate system. The model predicts that if greenhouse gas emissions continue to increase unchecked at current rates, absorption of atmospheric carbon dioxide by ocean and land sinks (currently about 50% of man-made emissions) will actually be replaced by carbon dioxide release. Such a carbon cycle feedback significantly enhances the projected rise in global temperature. Without the carbon cycle link, average global surface temperature is projected to rise by 5.5ºC. If realised, the Earth would become warmer than at anytime during the last 60 million years. For further information, contact the UK Meteorological Office website. Source: Global Environmental Change Report, 24th November 2000.
Britain is a nation of tea and coffee drinkers but the way we make our beloved cuppa wastes energy and harms the environment, latest statistics from the 'are you doing your bit?' campaign show. The nation drinks a staggering 229 million cups of tea and coffee every day. That's enough to fill 22 Olympic-size swimming pools. It works out at an amazing 9.5 million cups every hour, 159,027 cups every minute and 2,650 cups every second. But if each time we boil the kettle we use more water than we need, we also waste valuable energy and contribute to climate change. On average, we could all save 90 seconds each time we boil a kettle - by putting in only the amount of water we need. Such a simple action would also cut household electricity bills - overfilling each time we boil wastes enough energy in a week to light our house for a day or run a TV set for 26 hours. Although it is not possible to attribute the recent floods to global warming, climate change is expected to lead to rising sea levels and more frequent severe weather conditions - such as heavy rainfall with the increased risk of flooding - together with their growing economic and human costs. Source: DETR Press Release, 20th November, World hots up as Britain drinks 10 million cuppas an hour.
According to the US National Oceanic and Atmospheric Administration (NOAA), the summer period between June and August 2000 was again warmer than average by some 0.35ºC, but not the warmest summer on record. The greatest observed warmth occurred in parts of central Asia, including Siberia, Mongolia and northern China. In North America, some areas were warmer than average, including the western US and large areas of Canada, whilst other regions were close to or below average, such as the northeastern US. Source: Global Environmental Change Report, 13th October 2000.
Previous research has demonstrated that increases in surface temperature as a result of global warming may lead to a spread of vector-borne diseases such as malaria in previously unaffected areas. Now new model research from Oxford University published in the journal Science (Vol. 289) plays down these fears. Whilst previous models used by the Intergovernmental Panel on Climate Change have studied the affects of temperature increase only on the spread of malaria to northern latitudes, the new model used by Oxford University tests the affects of other variables such as humidity and rainfall. Although many areas currently untouched by malaria are expected to become warmer, increased dryness also predicted by global warming models for non-malarial areas would limit the spread of conditions conducive for the lifecycle of mosquitoes. Source: Global Environmental Change Report, 22nd September 2000.
An Indo-UK research programme on the impacts of climate change in India was launched on the 18 August 2000 in New Delhi, India. India's Ministry of the Environment & Forests (MoEF) and the UK's Department of the Environment, Transport and the Regions (DETR), have joined forces on a three-year study into the potential effects of global warming over the next 80 years. Indian scientists will carry out studies to build a comprehensive picture of the possible future impacts of climate change in India. The DETR will provide £650,000 to fund the initial studies and programme management. Collaboration between Indian and UK researchers will be encouraged. The project will also involve the UK's Hadley Centre for Climate Prediction and Research. The programme of research will include the development of climate change and socio-economic scenarios for India and assessment of impacts on water resources, agriculture, forests, industries, energy and transport, human health and coastal zones. Source: DETR Press Release, 18th August 2000
NASA is a little more than a year away from launching a satellite capable of making regular measurements of even the minutest changes in the thickness of the ice capping the Arctic, Antarctica and Greenland. The Ice, Cloud and Land Elevation Satellite, or ICESat, will carry a single science instrument, called Geoscience Laser Altimeter System, or GLAS, to accomplish the task, regularly tracking any changes in depth over time. It will rely on the speed of light and the spacecraft's location in space to carry out the monitoring. GLAS will bounce a laser beam down onto the ice 40 times a second, timing how long it takes for the pulse to complete the roughly 744-mile (1,200-kilometre) roundtrip, and making regular measurements of the changes to the thickness of ice caps. Scientists will use the data to track ice melt, which could lead to a rise in global sea levels. Whilst launch of the mission has been originally scheduled for July 2001, it is now likely to slip to later in the year. Once in orbit, the NASA Goddard Space Flight Center satellite mission will last anywhere from three to five years. Source: National Geographic News
A claim that the North Pole is ice-free for the first time in 50 million years was published in the 19th August edition of the New York Times. On a trip to the Arctic, Dr. James McCarthy of the American Museum of Natural History and the director of the Museum of Comparative Zoology at Harvard University witnessed the mile-wide ice-free cap. However, Dr Peter Wadhams, director of the Scott Polar Institute in Cambridge, argued that "Claims that the North Pole is now ice-free for the first time in 50 million years is complete rubbish, absolute nonsense . . . What is happening is of concern but it is gradual, not sudden or stupendous." Indeed, in a correction published in the 29th August edition, the New York Times said it had misstated the normal conditions of sea ice at the North Pole. It said open water probably has occurred there before because the Arctic Ocean is about 10% ice-free during a typical summer. The newspaper also said the lack of ice at the North Pole is not necessarily a result of global warming. Source: The New York Times; The Times; Polar News
Scientists from seven research institutions in Germany, the UK, and the US have discovered a previously unknown GHG: trifluoromethyl sulfur pentafluoride (SF5CF3). The gas is extremely rare, but concentrations in the atmosphere are increasing. It is also thought to be extremely longed-lived, in the order of 1,000 years. SF5CF3 has a climate change potential of 0.57 watts per square meter, per parts per billion concentration in the atmosphere. This is the largest climate change potential on a per molecule basis of any gas found in the atmosphere, some 18,000 times greater than the heat-trapping capability of the most common greenhouse gas carbon dioxide. The source of the gas is unknown, but there is some speculation that it is associated with high-voltage equipment. It is believed that the gas has been present in the atmosphere for only the past 40 years, suggesting strongly that it is man-made. Today, the concentrations of SF5CF3 in the atmosphere are rising at about 6% per year. However, the levels in the atmosphere are still relatively low and are unlikely to have a significant effect on global warming. Source: Global Environmental Change Report, 11th August 2000
Scientists at Ohio University in Athens, Ohio, USA, have embarked on a project to absorb carbon dioxide emissions at point sources. The researchers, backed by a US $1.07 million grant from the US Department of Energy (DOE), are studying how algae, through photosynthesis, can absorb some of the carbon dioxide produced after coal, a fossil fuel, is burned. Carbon dioxide is passed through tubes of moving water, creating bicarbonates. The water then flows through a bioreactor containing a series of screens on which algae grow. "The algae basically drink the bicarbonates. They get carbon through this system much quicker than trying to get it out of the air," says project researcher David Bayless. Once the algae mature, they sink to the bottom of the bioreactor and are harvested for other uses, such as fuel or a hydrogen source, fertiliser, or soil stabiliser. Bayless estimates that an average plant using this technology could process 20% of its carbon dioxide emissions and produce 200,000 metric tons or more of algae per year, which is efficient and cost-effective. The technology by itself however, will not solve the carbon dioxide problem for coal-burning power plants according to Bayless. Source: Global Environmental Change Report, 28th July 2000
ADAPTATION TO CLIMATE CHANGE WILL COST The latest research from the UK's Climate Impacts Programme (UKCIP), on behalf of the Department of the Environment, Transport and the Regions (DETR), indicates that the cost of improving coastal and river flood defences in England and Wales against the threat of rising sea level and increased rainfall, as a result of climate change, could cost over £1 billion over the next half a century. Areas particularly at risk from climate change include the low-lying areas of East Anglia, the Lancashire and Yorkshire/Lincolnshire coastlines, the Essex mudflats, the Thames estuary, parts of the north Wales coast, the Clyde/Forth estuaries and Belfast Lough. Despite the enormous cost of adaptation, the UKCIP believe that the cost of not responding to global warming could be over three times as great. Source: Global Environmental Change Report, 26th May 2000 Main menu | Home
NEW ROYAL COMMISSION REPORT ON ENERGY - THE CHANGING CLIMATE On June 16th, the Royal Commission on Environmental Pollution produced its 22nd Report on Energy – the Changing Climate. One of the key conclusions of the report reflects the viewpoint of the Intergovernmental Panel on Climate Change, that the UK should aim to reduce carbon dioxide emissions from the burning of fossil fuels by 60% by the middle of the 21st century. The Commission recommends that the UK Government’s goal of a 20% reduction of carbon dioxide emissions from the 1990 level by 2010 should become a firm target. However, the Commission doubts whether this target can be met with current measures. The Commission also considers that the UK lags behind many other European countries in renewable energy technology developments. Although the UK remains on course to achieve its Kyoto Protocol target of a 12.5% reduction in all greenhouse emissions by 2008-2012, current energy projections indicate that emissions may begin to rise again after this period. At present, the use of energy, predominantly in the form of fossil fuels, is continuing to increase, both worldwide and in the UK. The Royal Commission has investigated:
The Royal Commission report presents 19 keys recommendations which include considerably cutting energy usage in buildings of all types and a carbon dioxide fuel tax. The full report is available on the Royal Commission website at: http://www.rcep.org.uk/energy.html Source: Global Environmental Change Report, 26th May 2000; Royal Commission on Environmental Pollution website Main menu | Home
ANTARCTIC MELTING This March, one of the largest icebergs ever recorded broke off of Antarctica's Ross Ice Shelf. The immense block of ice - dubbed B15 - is 300 kilometres (186 miles) long and 37 kilometres (23 miles) wide, and is over a quarter of the size of Switzerland. Icebergs like B15 occur when ice at the edge of an ice shelf finally succumbs to the forces of the sea, which include warmer temperatures, currents and tides. According to the U.S. National Science Foundation's McMurdo Station in Antarctica the calving off of this tremendous iceberg is quite normal. Researchers believe that icebergs like B15 break away from all Antarctic ice shelves every 50 to 100 years as part of their natural cycle of ice loss and regeneration. According to iceberg observation records, the Ross Ice Shelf has been due for a major purge. Researchers also note that this event is probably not a global warming issue at this time, but scientists will be keeping an eye on this area to see if anymore very large icebergs break free in the near future. Source: Environmental News Network Main menu | Home
WARMEST WINTER ON RECORD IN THE U.S. According to the US National Oceanic and Atmospheric Administration (NOAA), the winter of 1999/2000 was the warmest in the United States since records began more than a century ago. This was the third year in a row of increasingly record warm winters, with average surface temperature during December to February 0.3oC above the previous year's record. Accompanying the record warmth has been a sustained period of drought for much of the continental US. Below average rainfall is predicted to continue into 2000 due to the La Niña pattern in the equatorial Pacific, the reverse (cold) phase of El Niño. More information can be found at NOAA's website at: Source: Global Environmental Change Report, March 24th 2000. Main menu | Home
In March the Department of the Environment, Transport & The Regions (DETR) published the 1998 emission estimates for greenhouse gases and other air pollutants, and a provisional 1999 estimate of total carbon dioxide emissions, for the UK. The key points to note are:
Source: DETR Press Release, 30th March 2000. Main menu | Home
There is now a growing consensus amongst both the scientific and business communities that the human fingerprint on the Earth's climate is real. Whilst it has been argued that the global warming observed throughout the 20th century is the result of natural variations, the record warmth at the close of the millennium indicates that man-made factors are more likely to blame. Analysis of temperature records stretching back 150 years, and tree-ring records prior to the instrumental period reveal that in the Northern Hemisphere, the 1990s were the hottest decade during the last 1000 years. In addition the 10 warmest years on record globally have all occurred since 1983, with the 4 warmest being 1998, 1997, 1995 and 1990. In England 1999 was the hottest ever, and the second hottest in the US. Whilst natural mechanisms affecting the climate (for example changes in output of energy from the Sun) have no doubt influenced the global temperature record, the apparent acceleration in warming towards the end of the 20th century is most readily explained by the rapid increase in greenhouse gas emissions during the post-war period. Despite better agreement between temperature observations and computer models predicting man-made climate change, it is not yet possible to determine whether the frequency of occurrence of extreme weather events will increase as a result of global warming. The Intergovernmental Panel on Climate Change (IPCC) recognises that whilst recent weather-related catastrophes such as Hurricane Floyd (September, 1999) and the flooding in Venezuela (December, 1999) may reflect shifting climatic patterns, it may simply be that people are being made more aware of their occurrence through improved information coverage. Source: Global Environmental Change Report, February 11th 2000. Main menu | Home
NORTH ATLANTIC OCEAN CIRCULATION & EL NIÑO El Niño is an unusually warm surface ocean current that develops every 2 to 7 years in the Tropical Pacific. During El Niño episodes, the warmer water piling up along the equatorial South American west coast produces enhanced levels of rainfall here, thereby reducing rainfall and river runoff into the equatorial Atlantic on the eastern side of the continent, and consequently increasing Atlantic Ocean salinity (saltiness). The last big El Niño occurred in 1998, resulting in the warmest year globally on record, and extreme weather related events all round the world. Some computer models have projected that global warming could lead to an increased frequency of occurrence of El Niño episodes. The North Atlantic circulation, in contrast, is a more permanent ocean current. Warm surface water from the equatorial Atlantic in the Gulf of Mexico travels north-westwards (the Gulf Stream), into the North Atlantic, before cooling and sinking. The sinking water, called the North Atlantic Deep Water, maintains the strength of the Gulf Stream, acting as a pulling force or conveyor belt. The presence of the warm Gulf Stream influences the climate of Western Europe, and in particular the UK, keeping winters many degrees Celsius warmer than they would otherwise be. Some scientists have suggested that global warming may slow or halt the North Atlantic Ocean Circulation. A melting Greenland icecap as a result of global warming could release considerable amounts of fresh water into the North Atlantic, decreasing the ocean's salinity, and therefore density, and slow or halt the deep water sinking. A slowdown in the North Atlantic Deep Water could equally slow or halt the Gulf Stream, and impact upon the regional climate. By modelling the effects of more frequent El Niños as a result of global warming, Researchers at the Max-Planck Institute in Germany have found the increased salinity in the equatorial Atlantic may actually help to maintain the strength of the North Atlantic Ocean Circulation. According to the model saltier water in the equatorial Atlantic as a result of an El Niño episode would be carried to the North Atlantic with the Gulf Stream and offset higher freshwater inputs as a result of enhanced icecap melting, stabilising the system and preserving the formation of North Atlantic Deep Water. Source: Global Environmental Change Report, December 24th 1999. Main menu | Home
AUSTRALIA HAS WORST EMISSIONS, PER CAPITA, IN THE WORLD The Australian Institute have recently produced a report, stating that Australia has the world’s highest greenhouse gas emissions per capita, from energy use, agriculture and land use and its related activities. By calculating per capita emissions for carbon dioxide (CO2), methane and nitrous oxide, the Australian Institute found that 1995 levels were nearly double the average of all other industrialised nations, and 25% higher than the United States. The calculations show that Australia’s annual per capita emissions totalled 26.7 metric tonnes of CO2. This compares to 21.2 metric tonnes in the US, with the industrial nations averaging 13.4 metric tonnes. Among some of the other nations ranking high on the list were Luxembourg, Canada and New Zealand. The full report can be viewed on the Australian Institutes web site: http://www.tai.org.au/Percapita3.htm Source: Global Environmental Change Report, 26 November 1999. Main menu | Home
SUBMARINES DETECT DECLINE IN ARCTIC ICE THICKNESS Scientists using submarines to measure ice thickness in the Arctic, have found that the thickness has fallen by 40% in the last 20 years. Over the entire deep water portion, average ice depths fell from about 3.1 metres in 1958-1976 to an average of just 1.8 metres in the 1990s. Evidence also shows that during the latter part of the 1990s the thickness has been declining at a rate of 0.1 metres per year. It is uncertain as to what has caused the decline. Possible climatic factors include changes in ocean heat flux, poleward transport of atmospheric heat, increases in short-wave radiation and changes in precipitation and snow cover. The findings were made by D. Andrew Rothrock and colleagues of the University of Washington (Seattle) and have been published in the 1 December issue of Geophysical Research Letters (vol. 26, pp.3469-3472). Source: Global Environmental Change Report, 26 November 1999. Main menu | Home
REVIEW OF CLIMATE CHANGE IN ANTARCTICA The British Antarctic Survey (BAS) have recently updated their position regarding climate change in Antarctica. Their statement recognised that although models used to predict climate change are unreliable, most agree that over the next 50 years, temperature rises are expected to be moderate and increased precipitation is expected to compensate for the increased melting of Antarctic ice. Reliability of models combined with lack of, and variability of long term records, makes it difficult to ascertain whether temperature changes in Antarctica will be in step with the rest of the globe. In recent years warming trends have been very small, with cooling in some parts. However, some areas do seem to be experiencing a more serious upward trend, with temperatures rising by 2°C over the last 50 years. It is this warming which is believed to have caused the melting of the Wordie and Larsen ice shelves. What is unclear, is whether trends are a result of human induced climate change, or part of a natural cycle. To view the full statement visit the BAS web site: http://www.nbs.ac.uk/public/info/antwarm.html Source: Global Environmental Change Report, 26 November 1999. Main menu | Home
|
CLIMATE CHANGE ISSUES |