Global Warming

The examination of a technical subject such as global warming requires that one be first conversant with it's terminology. In the case of climate change there are a good number of terms which are often used but frequently not properly understood.

Terminology

IPCG - Intergovernmental Panel on Climate Change: jointly established by the World Meteorological Organisation (WMO) and the United Nations Environment Programme (UNEP) in 1988 to assess available scientific and socio-economic information on climate change and its impacts and on options for mitigating it and adapting to it.

GHG - Greenhouse Gas/es: These gases allow sunlight, which is radiated in the visible and ultraviolet spectra, to enter the atmosphere. When it strikes the Earth's surface, some of the sunlight is reflected as infrared radiation (heat). Greenhouse gases absorb this infrared radiation as it is reflected back towards space, trapping the heat in the atmosphere. Greenhouse gases include carbon dioxide, methane, nitrous oxide, chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6).

• CO2 - Carbon Dioxide:Naturally occuring, consisting of two oxygen atoms bonded to one carbon atom. Increased industrial pollution from incineration of fossil fuels greatly increases atmospheric CO2 levels.

• N 2O - Nitrous Oxide: Consists of two nitrogen atoms bonded to one oxygen atom. N2O is far less common that CO2. It is also naturally occuring but it is up to 310 times more powerful at trapping heat in the atmosphere. Concntrations of N2O are increasing due to anthropogenic activities including agriculture, industry and waste-management.

• CH4 - Methane: Consists of one carbon atom bonded to four hydrogen atoms. As a contributor to the greenhouse effect methane is second only to carbon dioxide. In the last two centuries atmospheric concentrations of CH4 have more than doubled due to human activities - mostly agriculture.

• SO2 - Sulphur Dioxide: Consists of one sulphur atom bonded to two oxygen atoms. It is released naturally from volcanoes, fires and biological decay but also from fossil fuel combustion, smelting and waste incineration.

• SF6 - Sulphur Hexafluoride: Sulphur hexafluoride is another very potent greenhouse gas with a very high global warming potential. SF6 is principally used in magnesium production.

• CFC - Chlorofluorocarbon/s: Organic compounds that contain carbon, chlorine, and fluorine atoms. CFCs are highly effective refrigerants. When CFCs are released into the atmosphere they are broken down by ultraviolet light. The resulting free chlorine atoms (Cl) decompose ozone (O3 - see below) into oxygen (O 2).

• PFC - Perfluorocarbons: Perfluorocarbons (PFCs), e.g. tetrafluoromethane (CF4 ) and hexafluoroethane (C2F6), are greenhouse gases with a very high global warming potential in addition to an exceptionally long atmospheric lifetime. They are primarily produced during aluminium production.

• HFC - Hydrofluorcarbons: These chemicals were introduced to replace chlorofluorocarbons following the identification that they were the prime culprit for seasonal stratospheric ozone depletion at high latitudes, i.e. the hole in the ozone layer. However, hydroflurocarbons are one of the most efficient absorbers of infrared radiation and so are classed as greenhouse gases for this reason.

Ozone - Ozone (O3) : Is vital to human and animal survival because it is responsible for the absorption of the sun's ultraviolet light. Without this protection, blindness and skin cancers could result from penetrating ultraviolet light.

(ENSO) El Niño Southern Oscillation - El Niño (Spanish: "The Christ Child") - the appearance, on average every 3-4 years, of unusually warm ocean conditions along the tropical Pacific coast of South America which is associated with adverse effects on fishing, agriculture, and local weather from Ecuador to Chile.

Radiative Forcing - This is the change in the balance between radiation (sun's heat) entering the atmosphere and radiation leaving it.

Historical Background

• The study and recording of the climate and weather patterns as a science only began seriously in the last 150 years, although mankind has been attempting to predict it and prepare for it's caprices for millennia.
• In the late1960s and early 1970s the malign effects of industrialisation (air and water pollution, worker ill-health, acid rain) were recognised by several commentators on both sides of the Cold War ideological divide culminating in the Stockholm Conference of 1972.
• This increased awareness of the effect of man's behaviour on the biosphere coupled with the damage caused by acid rain to Scandinavian arboreal forest led to the adoption of environmental science as an academic discipline.
• 1979 3-Mile Island nuclear reactor disaster, Pennsylvania, USA.
• The 1982 adoption of the United Nations Convention on the Law of the Sea demonstrated that international agreements could be struck on environmental issues.
• 1985 The hole in the Earth's stratospheric ozone layer was first noticed over Antarctica.
• 1985 Vienna Convention on Ozone Depleting Substances established the framework to protect the ozone layer from harmful chemicals
• 1986 Chernobyl nuclear reactor disaster Ukraine, USSR
• 1990-1992 Montreal Protocol on Substances that Deplete the Ozone Layer was amended and ratified.
• 1992 Earth Summit, Rio de Janeiro - 122 nations signed a declaration stating their commitment to reducing CO2 emissions and agreeing to meet again in 1997 to review the situation.
• 1998 El Niño strikes Ecuador, Chile and Peru with torrential rains and high winds causing massive destruction and loss of life - one of the strongest and deadliest ever recorded. La Niña - a weather system corresponding to El Niño - follows leaving normally plentiful fish stocks depleted and dryer than usual climatic conditions.
• 1997 Kyoto Protocol: The United Nations Framework Convention on Climate Change.

Current Debate

Much of the current debate on climate change/global warming centres not on whether climate change is actually taking place but whether it is happening as a direct result of human activities or as part of cyclical warming and cooling trends natural to the Earth's atmosphere. It has been generally accepted for some time that the Earth's climate is warming, but scientists have struggled to categorically prove that this has been accelerated by the behaviour of mankind. This has led to scepticism and opposition on the behalf of politicians and industrialists to act to reduce the emission of greenhouse gases.

The most recent report by the Intergovernmental Panel on Climate Change (IPCC)1 concludes from an immense body of observations of all parts of the climate system that the picture is of a warming world. The report catalogues the increasing concentrations of atmospheric greenhouse gases and concludes that there is stronger evidence than in 1996 - the date of the IPCC's previous report - that most of the global warming observed over the past 50 years is attributable to human activities.

The 1997 Kyoto Protocol on Climate Change sought international agreement on action to reduce greenhouse gas emissions to below 1990 levels in order to slow the warming of the Earth's atmosphere. This met with only partial support from the nations of the developed world and did not include developing countries in its mandate. This lack of support was due to the perceived adverse effects that cuts in pollutants may have on fossil fuel-reliant economies.

This is despite the fact that global warming/climate change is widely recognised as a transnational problem, i.e. one which cannot be effectively tackled by one nation alone or by excluding one or more nation from the solutions. In fact, climate change is possibly the most global of issues - all nations contribute to it, no one nation can solve it and the effects of globalisation (air travel, polluting industries etc...) have contributed heavily to it's acceleration.

However critics of the green movement have argued that the predictions of climate change induced disasters predicted by environmental groups are either simply soothsayings with little evidence or are massive exaggerations. They believe that far from being in dire straits, mankind has actually vastly decreased it's malign impact on the environment since the dirty and less efficient industrial practices of the nineteenth century2 and that an increase in the use of wind and biomass energy would return mankind to a pre-industrial state.

Several environmental economists have suggested that it may be more cost effective, in relative terms, to simply deal with the consequences of climate change than to attempt to avert their onset through modification of human activities.

However, the truth of the matter is that mankind is currently unable to accurately predict exactly what the effects or not of global warming will be and it is with this in mind that we continue into the final section.

Impact of Climate Change

Several observations and predictions have been made of the effects of global warming on the Earth's atmosphere. These include the continuing rise in global mean temperatures, causing the melting of glaciers, ice-fields and ice-caps and consequent rising sea-levels and changes in patterns of precipitatiom. The effect of these phenomenon on the Earth's many and varied ecosystems is difficult to calculate precisely since, not only are the exact levels of temperature3 and sea-level rises unknown, but there also remain many ecosystems that have not been studied in sufficient depth for any projections in this regard to be meaningful. However, even if the lowest estimates for temperature increases4 continue, we are likely to witness changing and more severe weather patterns in tropical regions, warmer and wetter weather in the higher latitudes and decreasing winter sea-ice thickness in polar regions.

The ramifications of such changes in climate and weather patterns are again difficult to estimate precisely but may include the flooding of low-lying areas, islands and atolls, poorer crop yields, an increase in the range of disease-carrying mosquitoes, droughts and fires, less predictable season changes, species extinctions, coral reef bleaching and forced human population migrations due to deteriorating local conditions.

However, as suggested above it remains unclear whether all, some or none of this will actually come to pass. Therefore, the debate for the present will continue into the future. It will revolve around the question of whether waiting until the evidence is categorical will mean that it is too late to do anything meaningful; whether preemptive attempts will bear fruit if the perameters in which they are carried out are still unclear; or whether there is really anything that can be done to halt global warming. Whatever the answer though, the one certainty is that the solution, if there is one, will have to be a global one; one that tackles the problem on a global scale and one that curbs the worst excesses of globalisation.

Bibliography:

Daley, B., "Disease Threat Cited in Global Warming," Boston Globe, 21/06/2002

Lomborg, B., The Sceptical Environmentalist, Cambridge University Press, 2001

Pierce, J., Solzhenitsyn: Soul in Exile, Harper Collins, London (2001).

Schumacher, E.F., Small is Beautiful: Economics as if People Mattered, Hartley & Marks, New York (1973) (reissued 1999)

IPCC, Climate Change 2001: The Scientific Basis, UNEP/WMO, Cambridge University Press, (2001)

IPCC, Climate Change 1995: The Science of Climate Change, UNEP/WMO, Cambridge University Press (2001)

Burke, T., Ten Pinches of Salt: a reply to Bjørn Lomborg, Green Alliance, London (2001)

Websites:

Climate Hot Map.org (for information on effects and likely impacts of climate change) http://www.climatehotmap.org/

Courtney, R., Global Warming: How it All Began, from Still Waiting for the Greenhouse, on http://www.vision.net.au/

Planet Ark, "Chronology - The Fight Against Global Warming," 29/10/2001 "Factbox - Science on global warming behind Kyoto pact," 16/07/2001 on http://www.planetark.org/

Sierra Club (information on possible effects of global warming) on www.sierraclub.org/

Union of Concerned Scientists, "UCS Examines The Skeptical Environmentalist by Bjørn Lomborg," http://www.ucsusa.org/warming/

1 IPCC - Climate Change 2001: The Scientific Basis, UNEP / WMO
2 See Professor Bjorn Lombørg's The Sceptical Environmentalist and Richard Courtney's Global Warming: How it All Began.
3 During the 20th Century, the global mean temperature rise has been 0.6+/-0.2C.
4 Since the late 1590s the overall global temperature increases for the lowest 8kms of the atmosphere and in surface temperature have been 0.1C per decade.

Jonathan Sills is a Project Officer for The Environmental Trust. He holds a Masters degree in International Relations from Bristol University.
Email: sillsjonathan@hotmail.com

Placed on Fabian Global Forum, June 2002