Homework: What is the equivalent mass of cats flowing through the rivers each second? Table 1.1. Areas, volumes and heights of the ocean and atmosphere Atmosphere inventory Earth surface area Ocean surface area Ocean mean depth Ocean volume Ocean mass River flow rate 1.77 x 1020 mol (all gases) 5.10 x 10 14 m 3.62 x 1014 m (71% of Earth's area) 3740 m 1.35 x 1018 m 1.38 1021 kg 3.5 x 1013 m y Pilson (1998); the river flow rate is from Broecker and Peng (1982).