Noted Japanese environment experts have praised the Paris Agreement on a road map for combating global warming from 2020 on but at the same time, called on Japan to explore a more environmentally friendly energy policy with a reduced use of fossil fuels.

The Paris Agreement, which was struck at the COP 21 meeting of the U.N. Framework Convention on Climate Change in Paris from late November to December, was historically important, in that it encompassed all participating countries, including developing countries, according to Kazuo Matsushita, a professor emeritus of Kyoto University, Junichi Fujino, senior researcher of the National Institute for Environmental Studies, Japan, and Kazuhisa Koakutsu, senior researcher of the Institute for Global Environmental Strategies.

Referring to the challenges that must be addressed in the years to come, the three experts stressed that 2016 should be the year that the world realizes specific results toward achieving the warming limit targets contained in the landmark accord. The three researchers took part in the meeting in the Le Bourget district of northeast Paris.

　In a recent debate organized by independent Japanese think tank The Genron NPO, Matsushita noted that the 2 degree Celsius and 1.5 degree Celsius warming limits on the increase in average temperatures were clearly mentioned in the accord as long-term goals for the participating countries.

If the 2 degree target is to be attained, greenhouse gas emissions will have to be reduced to zero or negative levels in the second half of the 21st century, but the target cannot be achieved only with the measures presented by the participating countries in their Intended Nationally Determined Contributions, or INDCs, Matsushita said.

The countries involved should pursue a more ambitious target as early as possible and then, further stimulate efforts by industry, local governments and civic groups to combat global warming, he said.

Koakutsu called attention to the twin notions of "mitigation" and "adaptation" contained in the Paris Agreement each for eliminating greenhouse gas emissions and curbing the damage inflicted by global warming. The targets are expected to be achieved by enhancing mutual cooperation through technology transfer, financing and capacity-building, but how this mechanism will work should be studied, he said.

Worldwide efforts to achieve a zero-carbon society should continue by, for example, using new systems such as the carbon isolation and storage technology designed to bury underground or undersea factory-originating carbon dioxide and a biomass energy generation system that can absorb carbon dioxide, Fujino said.

Genron NPO President Yasushi Kudo, who served as moderator at the three-way debate, asked the participants to discuss the course of Japan's energy policy amid increasing efforts around the world to shift from fossil fuels.

The Japanese government adopted a new energy mix policy toward 2030 in June 2015, envisaging covering 20 percent to 22 percent of Japan's energy needs with nuclear power by restarting the nuclear power stations halted since the March 2011 devastating earthquake and ensuing tsunami, and increasing the ratio of power generated with recyclable energy sources from 22 percent to 24 percent. But Japan will have to rely on burning coal for the greater part of its energy needs in the years ahead.

The United States and many other countries are gradually moving away from coal-burning power generation while coal consumption is declining in China, Matsushita said.

The World Bank and other public lenders for undertakings in developing countries are reducing assistance for coal-burning power generation projects while investors around the world are withdrawing their money from coal-related ventures, he said. Plans to build more coal-burning power stations in Japan and moves to extend assistance to coal-burning plant projects in other countries are somewhat incompatible with the global trend toward less dependence on fossil fuel energy, Matsushita warned.

Japan's INDC presented at the COP21 meeting was largely ignored by other participating countries, according to Fujino. The indifference is attributable to the fact that global warming had not been fully considered in the process leading up to the adoption of Japan's energy mix policy last year, he said.

The decision process rather focused on matters related to national security, Fujino said. There has been no discussion about whether such a national security-oriented approach will continue to be effective in covering Japan's future energy needs with imported resources, he said.

Japan's INDC envisaged reducing its greenhouse gas emissions in 2030 by 26 percent compared with the 2013 level, but other participating countries viewed this as unsatisfactory, said Koakutsu. Because it is globally believed that Japan's manufacturers have achieved a very high level of energy saving in their operations, Japan was urged to come up with a more ambitious plan to combat global warming, he said.

The three participants also recalled that Japan's leadership was less visible in the course of negotiations at the Paris meeting, including sessions organized by the "coalition of ambition" combining island countries and developed countries.

Japanese Prime Minister Shinzo Abe attended the meeting and took the occasion to announce the provision of \1.3 trillion a year to developing countries to help contain the influence of climate change. Japan also exchanged a memorandum with the Philippines toward establishing a bilateral gas emission credit system between the two countries. But these moves did not contribute to visibly showing Japan's various endeavors to combat global warming, Koakutsu said.

The three experts warned against the unabated adverse effects of global warming despite years of efforts to reduce greenhouse gas emissions around the world.

The effects of global warming have been expected to appear as long-term phenomena, but there are abnormal meteorological incidents that can be seen as short-term consequences linked to global warming, Fujino said. Since countries are already suffering the effects of global warming, they cannot wait, they need to act now, he said.

They should simultaneously grapple with the double tasks of reducing greenhouse gas emissions as the cause of global warming and adapting themselves to ongoing global warming, Matsushita said.

The Japanese government came up with its adaptation program in October, but Japan should prepare a proper mitigation program for reducing its greenhouse gas emissions following the Paris Agreement, he said.

The world's countries should build a society on the assumption that they will have to live with global warming, Koakutsu said. "In a sense, all countries have become aware of such a situation," he said. "We have to live with the assumption that global warming exists," he said.