Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India and north of Australia. The climate in Southeast Asia is mainly tropical–hot and humid all year round with plentiful rainfall. Southeast Asia has a wet and dry season caused by seasonal shift in winds or monsoon. The rain forest is the second largest on earth (with the Amazon being the largest). An exception to this type of climate and vegetation is the mountain areas in the northern region, where high altitudes lead to milder temperatures and drier landscape. Other parts fall out of this climate because they are desert like.