It will also be essential to secure enough food supplies.

At the root of the world's energy predicament is the mass consumption of fossil fuel since the Industrial Revolution. The warming of the Earth's surface caused by modern society's heavy dependence on fossil fuels has exacerbated the food problem.

These are the multiple challenges confronting the world. What the world needs to do now is to take a big step toward eliminating the root cause of all these nagging problems.

Progress in such efforts will not just resolve economic problems but will also help nip potential international conflicts in the bud and build world peace.

Former British Foreign Secretary Margaret Beckett, who has contributed to spreading the term "climate security", described the dire situation of the world during a symposium on environmental problems.

Since the beginning of human history, wars have been fought repeatedly over limited resources like land, water, food and fuels, Beckett said. But we are now in an unprecedented situation in which almost every area on the Earth is under such pressures concurrently, she argued.

Sea levels rise. Farmland decreases. The world map of epidemics of infectious diseases changes. All of these potential problems are believed to be among the evil effects of global warming. These disastrous changes could trigger massive population migrations, generating new refugee crises and regional conflicts.

Effective efforts to stem global warming are indispensable to help prevent such destabilization.

One immediate question concerning the fight against global warming is how much progress will be made at the G8 summit at the Lake Toyako resort.

During last year's summit, held in Heiligendamm, Germany, the G8 leaders agreed to "consider seriously" the goal of halving world's greenhouse gas emissions by 2050.

The meeting of the Conference of Parties to the UN Framework Convention on Climate Change held late last year produced an international agreement to complete by the end of 2009 a new framework for tackling global warming.

The new framework is supposed to succeed the Kyoto Protocol, whose first commitment period obliging industrialized countries to reduce CO2 emissions expires in 2012.

At the Lake Toyako summit, the G8 nations must at the very least adopt a formal international goal of halving global greenhouse gas emissions by 2050. In addition, they should make clear a medium-term target for ensuring the achievement of the long-term goal.