Annan said the damage caused by the tsunami makes it "no longer so hard to imagine" what might happen from the rising sea levels that scientists say will accompany global warming.
Annan was speaking at a UN conference in Mauritius on the world's small islands. The weeklong conference is looking at ways to help some of the world's most vulnerable states cope with hazards and disasters such as the 26 December tsunami that killed more than 150,000 people and devastated 12 countries.
Officials from small island states such as Kiribati, Tuvalu, the Marshall Islands, and a handful of other low-lying island states are pressing for action on climate change. Such states, threatened by the rise in the sea level caused by global warming that could see them entirely submerged, say they are facing resistance from countries who have not signed the Kyoto Protocol on climate change.
Annan told participants that all countries, even those who have not signed the protocol, have an obligation to avoid global warming. "The issue you raised of climate change and global warming is a very important one. It's an issue that is of great concern to the UN and to the entire world community. We're all aware of the Kyoto Protocol which not all countries have signed but many have," Annan said. "But I would say whether one has signed the protocol or not, we all have a responsibility to try and reduce the emissions and avoid global warning which has direct impact on small island states."
Annan's remarks came one month before the coming into force of the Kyoto Protocol. The agreement will see 38 countries reduce their greenhouse-gas emissions, seen as the main cause of global warming. But the United States, one of the world's biggest polluters, has refused to endorse the protocol.
Annan arrived in Mauritius after touring tsunami-hit Indonesia, Sri Lanka, and the Maldives. He reiterated calls for the creation of a global early-warning system to avert future tsunami catastrophes.
The UN Educational, Scientific, and Cultural Organization (UNESCO) is leading an effort to set up a global early-warning system. UNESCO announced yesterday that a $30 million Indian Ocean tsunami-alert system would be launched in June 2006, with the rest of the world to follow in 2007 for a total cost of some $130 million.
Annan said yesterday the new system should cover the whole world and focus not just on tsunamis, but also on other threats "such as storm surges and cyclones."
Annan addressed young people engaged in a UNESCO project involving island states. "We recently saw what the environment can do to these states through the tsunami catastrophe," he said. "But you did not only focus on what should be done, you touched on social development, you touched on education, community development, the role of the youth and above all, you seemed ready to assume your own responsibility."
In his address to the leaders of the world's more than 40 island states, Annan said the international community must redouble its efforts to help small developing countries. For some island states, Annan concluded, "their very existence is in jeopardy."