In a large, air-conditioned room in a conference center located in a city of more than a million people, well-qualified doctors of science discuss the pros and cons of global warming, and debate how the temperature of the sea is being measured. After several hours of discussion, they walk out into the warm sunshine of a summer"s day, heading off to a comfortable restaurant for lunch. On the same day, on the sands of small islands in the middle of the Pacific Ocean, baked hard by the burning sun, Hemi and Naqono look at the water lapping over the place where they once stored their potato plants. They watch the waves dashing gently at the feet of their straw huts which some years ago were many metres from the seashore. Global warming is a problem for theoretical discussion among scientists all over the world. For many Pacific Islanders it is now becoming a practical problem. While international science argues about global warming and climate change, low-lying Pacific Islands are already suffering coastal erosion and crop failures. In places such as Marshall Islands, where much of the land is only a metre above sea-level, villagers face leaving their slowly disappearing homes. Scientists and officials from 13 Pacific Island Countries discussed their concerns in a Pacific conference in Aukland, New Zealand, and examined a New Zealand computer model on climate change that could provide a valuable planning tool. Lack of meteorological and tidal research means Government agencies throughout the Pacific and the world have to rely largely on anecdotal of rising sea levels eroding foreshores, and increasingly severe droughts affecting the vital coconut crop. Australian research commissioned by the South Pacific Regional Environment Programme has already calculated that human greenhouse gas emissions already measured up to 1995 will cause a 5cm to 12cm sea-level rise by 2025. Pacific Island countries fear their vulnerable low-lying homes will be the first to pay the price for the emissions of industrialized nations. A Pacific Islands Climate Change Assistance Programme is already in place and is working on plans to help Pacific Islanders who have few resources to combat the fast-changing environmental circumstances. Yumi Crisostomo, of the Marshall Islands Environmental Protection Authority, said residents of some of the 1,225 islands in the group had reported alarming coastal erosion, forcing them to shift homes inland. Some islands were only about a kilometer across, so residents had little room to move. "We may have to look at the option of internal migration within the island group," he said. The first two paragraphs suggest that

A. global warming is not only a theoretical problem but also a practical one.
B. there is a great difference between the rich and poor.
C. science discussion has nothing to do with the practical problem.
D. well-qualified doctors know little about the reality of the problem.