The Fourth Assessment Report of the Intergovernmental Panel
on Climate Change (IPCC) indicated that the mean temperature in
Thailand will raise by 2.0e5.5 C by 2100 under the regionallyoriented
economic development scenario of the Hadley Centre
Coupled Model, version 3 (HadCM3 A2) (IPCC, 2007). Boonpragob
and Santisirisomboon (1996) predicted that the temperature in
Thailand will increase by 1.5e2.0 C and annual rainfall in the south
will increase by 40% by 2100. These changes would cause effects on
Thai forests. The area of the subtropical life zone would decline
from about 50% to 12e20% of the total cover, whereas the tropical
life zone would expand its cover from 45% to 80%.