More than $70 \%$ of world's freshwater is contained in

Three fourth surface of earth (about $71 \%$ of total) is occupied by oceans which contain $97.5 \%$ of total water. This is marine water with about $3.5 \%$ salt contents. Rest water i.e., $2.5 \%$ is freshwater, which occurs on land. Most amount of this water (about $1.97\%$) occurs as frozen ice caps and glaciers and $0.5 \%$ freshwater occurs as ground water.