The “greenhouse effect” is occurring. Without it, the earth would have an approximate average temperature of -18ºC instead of the milder +15ºC it now enjoys. The concerns of global warming are based on the “enhanced greenhouse effect” (EGE): raise the level of greenhouse gases and the ambient temperature will increase. Although the concept is simple and straightforward, the science and predictability on which it is based is exceedingly complex.[xxii]
In a simplistic model (one that is not entirely correct), the earth and atmosphere can be viewed as a greenhouse. The atmosphere is treated as a thin piece of glass. In the greenhouse, sunlight passes through the glass, strikes the floor and warms it. As the temperature rises, the floor emits a greater amount of infrared energy. The infrared energy warms the glass, which then emits radiation both outwards (into outer space) and back towards the floor. This result (the greenhouse effect) creates the effect that the floor (or the planet) receives energy from two sources: the sun and the glass (the atmosphere). The fear of the enhanced greenhouse effect is increasing the amount of energy from the glass.[xxiii]
This overly simplistic model adequately describes the greenhouse effect but fails to address many components of the enhanced greenhouse effect. The problem is that many of the individual components and their interactions (feedback mechanisms) are not well known or understood.
The infrared radiation emitted by the warmed earth has too little energy to interact with diatomic molecules (O2 and N2) which comprise >99% of the atmosphere. The infrared radiation interacts with triatomic and other complex gases. The primary greenhouse gas is water; although the concentration of this triatomic molecule is variable (0-4%), its concentration is greater than any other complex molecule. The other two major greenhouse gases are carbon dioxide (CO2) and ozone (O3).[xxiv]
Although water is responsible for almost all of the observed 33ºC greenhouse effect, it absorbs the surface radiation over a broad band of wavelengths. Ozone traps radiation closely centered around 10 microns while carbon dioxide traps radiation around 15 microns. Carbon dioxide is very efficient in trapping this radiation. This efficiency is the basis of some ‘skeptics’ disbelief: increasing the amount of carbon dioxide can only increase the amount of energy trapped by a ‘small’ amount due to the efficiency of the amount already present. However, this does explain the importance of controlling emissions of complex man-made molecules (i.e. CFC’s) that absorb radiation in an area of the spectrum that would normally pass through the atmosphere.[xxv]
The other components and feedback mechanisms of the greenhouse effect are very complex, uncertain and beyond the scope of this paper. The existence and certainty of these elements are central to the controversy of how much warmer will the earth become. (Brief examples include: increasing the CO2 level increases the temperature, thereby increasing the amount of water in the atmosphere, further increasing the temperature; or, increased temperatures thicken the thermocline in the ocean, inhibiting turnover rates, thereby decreasing the amount of carbon sequestered in the ocean and thereby increases the amount of CO2 in the atmosphere raising the temperature further; or increased concentrations of CO2 will stimulate growth in plants, thereby slowing increases in the concentration of CO2.)
The anthropogenic influence on the greenhouse effect was first theorized by Arrhenius at the end of the 19th century.[xxvi] Arrhenius believed that the global warming would result in “ages with more equable and better climates, especially as regards the colder regions of the Earth.” (He lived in Sweden.) The issue was raised again in 1938 by Callender.[xxvii] Many people discounted Arrhenius’ and Callender’s theories instead believing that the oceans would absorb more carbon dioxide than the atmosphere because of its role as an immense reservoir. In 1957, Roger Revelle and Hans Suess, both from the Scripps Institution of Oceanography, argued that there are limits on how much carbon dioxide the oceans can absorb and atmospheric levels must be rising. Instrumentation, at this time was too crude to accurately measure CO2.[xxviii]
Soon a technique was developed to accurately measure the concentration of CO2 in the atmosphere. Records of measurements were begun at Mauna Loa, Hawaii. An increase of CO2 was evident from the data collected.[xxix] The main controversy in the global warming arena is not whether it is occurring, but what will the magnitude of the temperature increase be. Most climate models predict that with a doubling of the pre-industrial concentration of CO2 (expected to occur around the year 2100) the global average surface temperature should rise from 1 to 3.5ºC.[xxx] ‘Skeptics’ believe that the resulting change from doubling the concentration of CO2 would raise the temperature by 1-1.5ºC.[xxxi]
The first significant international response to climate change occurred in 1979: the First World Climate Conference was held in Geneva. At this conference, the “Declaration of the World Climate Conference" was adopted. This declaration urged the nations to take advantage of the present knowledge of climate, improve that knowledge, and to foresee and to prevent potential adverse man-made changes in climate. The formation of the World Climate Programme (WCP) was also proposed.[xxxii] The WCP was formed and research progressed, however, little more was accomplished until the record-breaking temperatures of the late 1980’s occurred.[xxxiii]
In the fall of 1987, an international workshop was held in the cities of Villach and Bellagio, Italy where the issue of climate change was raised and discussed. Forty-eight countries met in Tokyo the following year and recommended a twenty percent reduction of 1988 CO2 emissions levels by industrialized countries by year 2005. In addition to these meetings, the Intergovernmental Panel on Climate Control (IPCC) was formed by UNEP and the WMO in November 1988.[xxxiv]
The IPCC was to assess the scientific information on climate change, as well as the impacts of and response to climate change. The IPCC published its first assessment in August 1990. The report recommended immediate international negotiations on a framework convention. UNEP and WMO convened an ad hoc working group to prepare for negotiations; however, the group could not agree whether to continue within the existing IPCC process or to work with a special conference.[xxxv]
General Assembly resolution 45/212 answered the question by establishing the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change (INC/FCCC). A significant milestone was reached in 1992 with the adoption of the U.N. Framework Convention on Climate Change (FCCC).[xxxvi] The Convention entered into force in March 1994. One of the more important elements of the FCCC was the establishment of a negotiating body, the Conference of Parties (CoP), to consider more stringent measures for climate change protection.[xxxvii]
The next significant milestone occurred in 1997 at CoP-3 in Kyoto, Japan. The Kyoto Protocol was adopted. The protocol contains several interesting elements. A list of greenhouse gases is given in Annex A. The protocol also sets legally binding emission targets for Annex I parties (developed countries).[xxxviii] The Annex I parties will, generally, have to reduce their emissions to a certain percent of 1990 levels, as specified in Annex B, to be achieved as an average over the 5 years 2008-2012.[xxxix] In calculating emissions, the amount of carbon sequestered in “sinks” may be deducted from the amount emitted.[xl] However, 1995 may be used as the base year for the ‘exotic’ greenhouse gases.[xli]
The Kyoto Protocol shall enter into force when 55 parties, which account for at least 55% of the total carbon dioxide emissions for 1990, have ratified the protocol.[xlii] Although eighty-four parties have signed the protocol, only nineteen have ratified it, none of which is a major emitter of greenhouse gases.[xliii] Without the ratification by the United States (34.1% of total emissions)[xliv], it will be difficult to reach the 55% of emitters required for ratification.
[xxii] Philander, Is the Temperature Rising?, p.35, (1998).
[xxiii] Id. at 221.
[xxiv] Id. at 36.
[xxv] Id. at 51.
[xxvi] Arrhenius, Philosophical Magazine, 41, 237 (1896).
[xxvii] Callendar, Journal of the Royal Meteorological Society, 64, 223-40 (1938).
[xxviii] Revelle and Suess, Tellus, 9, 1827(1957).
[xxx] Intergovernmental Panel on Climate Change
[xxxi] http://www.newscientist.com/ns/970719/features.html, interview with Pat Michaels.
[xxxiii] Halpern, U. N. Conference on Environment and Development: Process and Documentation 1992.
[xxxvi] Morrissey, Global Climate Change: A Concise History of Negotiations and Chronology of Major Activities Preceding the 1992 U.N. Framework Convention, 1998.
[xxxvii] United Nations Framework Convention on Climate Change, Art. 7 (1994).
[xxxviii] Kyoto Protocol to the United Nations Framework Convention on Climate Change, Art. 3.
[xxxix] Id. at Article 3.
[xl] Id. at Paragraph 3.
[xli] Id. at Paragraph 8.
[xlii] Id. at Article 24.
[xliv] Official Data reported to the Climate Change Secretariat.