Due to global warming, polar ice-caps and glaciers are melting fast than the time taken for new ice layers to form sea water is also expanding causing sea level to rise. Due to melting of glaciers, rivers overflow and cause floods. Correct Answer Due to global warming, polar ice-caps and glaciers are melting fast than the time taken for new ice layers to form sea water is also expanding causing sea level to rise. Due to melting of glaciers, rivers overflow and cause floods.