This Convention was opened for signature at the UN Conference on
Environment and Development held in Rio de Janeiro in June 1992, came into
force in 1994 and has been ratified by over 170 Parties. The Convention's
principal policy-making body is the Conference of the Parties, which is
supported by a number of subsidiary bodies and working groups and which
often calls on the Intergovernmental Panel on Climate Change (IPCC) for
scientific and technical advice. The Convention is supported by the Climate
Change Secretariat, which is based in Bonn.
The Convention has the objective of stabilizing greenhouse gas concentrations at a safe level within an acceptable time frame. It contains a series of commitments requiring all Parties to develop national inventories of greenhouse gas emissions; to formulate national programmes to mitigate climate change; and to promote technologies, practices and processes that control, reduce or prevent emissions in all relevant sectors, including transport. The Convention also requires that the developed countries and countries with economies in transition (the "Annex I countries"), individually or jointly, return greenhouse gas emissions to their 1990 levels by the end of the present decade, although this is expressed as a general aim rather than a binding commitment.
In March 1995, the First Session of the Conference of the Parties created "the Berlin Mandate", which called for the negotiation of strengthened commitments by the Annex I countries. This led to the adoption of the Kyoto Protocol to the Convention in December 1997 by the Third Session of the Conference of the Parties (COP/3). The Kyoto Protocol requires Annex I countries to reduce their collective emissions of greenhouse gases by approximately 5 per cent by the period 2008-2012, calculated as an average over these five years and with the actual reduction varying from country to country. For the three most important greenhouse gases (carbon dioxide, methane and nitrous oxide), the base-line continues to be the corresponding levels in 1990. If compared with expected emission levels for the year 2000, the total reductions would actually be about 10 per cent, because many Annex I countries have not succeeded in meeting the aim of returning their emissions to 1990 levels by the year 2000, and their emissions have in fact risen since 1990. Compared with the expected emission levels by 2010 without emissions-control measures, the Protocol target represents a 30 per cent cut. The agreed targets apply to national totals of greenhouse gases. Consequently, each Annex I country can determine how the various emission-producing sectors in its economy should be called upon to assist in achieving the country's national target.
The Kyoto Protocol also contains a number of innovative features such as a "clean development mechanism" which will enable Annex I countries to finance emissions-reduction projects in developing countries and receive credit for doing so; and an international "emissions-trading" regime which will be established to allow Annex I countries to buy and sell excess emissions credits amongst themselves. The operational details for these schemes have yet to be elaborated.
The Kyoto Protocol was opened for signature for one year from 16 March 1998. It will enter into force after it has been ratified by at least 55 countries representing 55 per cent of the total 1990 carbon dioxide emissions from Annex I countries.
While the Convention does not specifically refer to civil aviation, in principle it applies to all sources of emissions. Two aspects of particular relevance for aviation are the methodologies used for compiling national greenhouse gas inventories and a specific provision in the Kyoto Protocol referring to ICAO. Each is considered separately below.
In order to assist Parties in compiling their national inventories
of greenhouse gas emissions, guidelines have been developed by the IPCC,
with the help of the Secretariats of the Organisation for Economic Co-operation
and Development and the International Energy Agency. Insofar as quantification
of aviation emissions is concerned, experts from ICAO's Committee on Aviation
Environmental Protection (CAEP) have contributed to the development of
the methodology that is being used.
Once aviation emissions have been quantified, an important distinction is whether the emissions are domestic or international. For domestic flights, the emissions are considered to be part of the national inventory of the country concerned. However, for international flights, the difficult question arises as to how to allocate the emissions (referred to as "emissions from aviation bunker fuels" in UNFCCC terminology) to national inventories. To give an illustration of the problem, if an aircraft registered in Germany loads fuel in Montreal and flies to Frankfurt with passengers of many different nationalities, producing greenhouse gas emissions in the airspace of several countries en route, to which country's national inventory should these emissions be allocated?
The UNFCCC's Subsidiary Body for Scientific and Technological Advice (SBSTA) has been wrestling with this question ever since the Convention entered into force and has suggested a number of options, including:
However, since these options can lead to very different allocations
of the emissions from international aviation, there has so far been no
agreement on which option to choose. In the meantime, the practice recommended
to Parties is that they collect information on international aviation emissions
on the basis of the fuel sold in their country and submit it to the UNFCCC
Secretariat along with their national inventories, but that they keep the
international aviation amounts separate and do not include them in calculating
their national totals of greenhouse gas emissions. International marine
emissions are dealt with in a similar manner.
In Kyoto, COP/3, in its Decision 2/CP.3, urged SBSTA to further elaborate on the inclusion of international aviation and marine emissions in the overall greenhouse gas inventories of Parties.
In April 1995, the First Session of the Conference of the Parties
decided that the Conference's subsidiary bodies, taking fully into account
ongoing work in governments and international organizations, including
ICAO, should address the issue of the allocation and control of emissions
from international bunker fuels. The fact that this decision referred not
only to "allocation", but also to "control", was brought to the attention
of the Council during its 145th Session. The Council's subsequent report
to the 31st Session of the Assembly recognized the need for ICAO to contribute
where appropriate to the UNFCCC process, while seeking to ensure that insofar
as the control of emissions is concerned, the UNFCCC process does not duplicate
the work of CAEP.
In its May 1996 review, the Council noted that concerns raised about aviation's contribution to climate change need to be properly addressed and, if necessary, appropriate action would need to be taken to mitigate the problem. It was therefore essential that States reach a common understanding about how these concerns would be addressed, taking into account the respective mandates of ICAO and the UNFCCC process, the skills and resources available in each case, and the need to avoid duplication of efforts. In these circumstances, the Council confirmed its willingness to co-operate with the UNFCCC process and requested the Secretary General to liaise with the Convention Secretariat with a view to reaching a common understanding on the respective roles of ICAO and the UNFCCC process in this regard. Shortly thereafter, in July 1996, at the Second Session of the Conference of the Parties (COP/2), the President of the Council made a statement outlining the Council's position.
At the Third Session of the Conference of the Parties in Kyoto, international aviation emissions were not included in the agreed targets, because of the difficulties that had arisen over the methodologies for allocating these emissions. The question of how international aviation emissions would be treated was considered in the context of discussions on policies and measures that might be pursued by the Annex I countries. Prior to COP/3, proposed policies and measures included some to address international aviation, working through ICAO, and some countries also wished to see specific details on certain aspects such as aviation fuel taxation. ICAO's views were made known in Kyoto and the Protocol finally adopted includes text on international aviation which refers to "working through ICAO" but which does not single out any specific measures. The relevant text (Article 2, paragraph 2 of the Kyoto Protocol) reads as follows:
The text in the Kyoto Protocol provides a welcome clarification
of the respective roles of ICAO and the Conference of the Parties to the
UNFCCC. It is now clear that ICAO is the forum where emissions from international
aviation are to be addressed. While ICAO is already active in addressing
greenhouse gases from aviation, this development faces ICAO with the challenge
of finding appropriate means of limiting or reducing greenhouse gas emissions
from international aviation or, failing that, of explaining to the COP
why this cannot be achieved.
When the Council's Committee on Aviation Environmental Protection (CAEP) met in April 1998, it agreed on a revised work programme on emissions that takes the Kyoto outcome fully into account CAEP has set up groups on both the technical aspects and the operational aspects of emissions, and will study market-based options for emissions reduction. CAEP has also established a Focal Point on Liaison, provided by the Secretariat and assisted by working group rapporteurs, with the task of continuing to liaise with the UNFCCC process and of initiating reports on progress made to limit or reduce greenhouse gases from aviation. There will also be continuing liaison with SBSTA regarding the allocation question, which could now take on a greater significance for ICAO.