Tropical monsoons are seasonal winds that blow from land to sea in tropical regions. Monsoons are caused by differences in air pressure between land and sea during different times of the year. During the summer, the land is hotter than the sea, causing air to rise and blow away from the land. During the winter, the land is cooler than the sea, causing air to sink and blow towards the land. This creates seasonal winds that bring heavy rains and cause flooding in some regions.