It is defined as the phenomenon in which the earth's atmosphere traps the heat from the sun and prevents it forms escaping it into the outer space thereby leading to an increase in the temperature of the earth's surface.
The temperature of the earth keeps on increasing causing melting of ice of glaciers which results in flooding of rivers, overflowing of rivers, and flooding of a large portion of land.
The gases in the earth's atmosphere that collects heat and light from the sun are called greenhouse gases.
The greenhouse gases are carbon dioxide(), methane (), and water vapor.