The International Federation of Red Cross and Red Crescent Societies said governments can do this by tackling food shortages, supplying clean water and increasing awareness among citizens about how to cope with disasters.
"We cannot stop climate change, we can only slow down the speed of climate change," said Tadateru Konoe, president of the group.
World leaders will meet in Copenhagen next month for a key climate summit. US President Barack Obama and other leaders have said it is unrealistic to expect the summit to complete a full treaty to cut greenhouse gas emissions.
A major issue at next month's meeting is how much wealthy countries will give poor countries to cope with climate change.
Konoe said that the world is already late in dealing with people affected by climate change that has become a major driver of weather disasters affecting millions of people worldwide.
He said the number of people affected has risen to about 243 million in recent years, from 190 million a year in the 1990s.
"It is a real and present threat. We must not delay action," Konoe said.