地球温暖化対策の世界的フレームワークに関する研究

Abstract

The world total of annual emission of CO2 was 5.9 GtC in 1989, while its stock in the atmosphere was 750 GtC. If the annual emission continues to increase with a growth rate of 3 % over the next half century, the accumulated total emssion will be as much as 650 GtC. More than a half of it will remain in the atmosphere, and this increment enevitably will cause the climatic changes as predicted in the report of IPCC. If this total mass balance of CO2 is considered, the global warming can not be prevented without strictly limiting the total amount of fossil fuels to be used over the long future time. In today's political climate of the world, it is difficult to achieve a unanimous international agreement on such limitations. Nevertheless, it would become necessary to establish a certain international framework to allocate the allowable limits of CO2 emission to countries. For this purpose, this paper discusses the establishment of a new economic realm in which ecological values are properly incorporated in the markets. Special attention is given to the use of economic tools in environmental policies, such as environmental taxes or charges and tradable emission permits system of CO2. Possibilities of introducing these tools are discussed according to the set of criteria prescribed by OECD, i.e., environmental effectiveness, economic efficiency, equity, administrative feasibility and public acceptance.