Because winter air pollution becomes heavier and heavier in the northern regions of China, more and more older people, especially those suffering from pulmonary diseases, just as migratory birds fly south every winter, have been going to southern cities in winter time for a more pleasant environment with higher temperature and cleaner air. So we call them migratory birds population (MBP). In Sanya, these people had better quality of life and activity tolerance than living in the north, which may be associated with environmental change. Remote sensing technology is an effective way to continually, rapidly and dynamically monitor the large-scale environment, so it can provide a basis for selecting a suitable place for MBP.