heat of fusion of water at 0°C = 79.71 cal/g

heat of vaporization of water at 100°C = 539.55 cal/g

standard acceleration of gravity, g = 980.66 cm/sec²

velocity of light in vacuum, c = 2.9979 × 10¹⁰ cm/sec

perfect gas constant, R = 8.3143 joule (g mole)^-1 (deg K)^-1

Avogadro's number, N _A = 6.0226 × 10²³ molecules/g mole

Stefan-Boltzmann constant, σ = 5.6697 × 10^-8 Wm^-2 °K^-4

Planck's constant, h = 6.6255 × 10^-34 joule-sec

Boltzmann constant, k = 1.3805 × 10^-23 joule/°K

DISTANCES (km) : equatorial radius = 6378, polar radius = 6357, equatorial circum-
ference = 40,074, mean elevation of continents = 0.8, mean depth of oceans =
3.8, mean distance to sun = 149.5 × 10⁶

AREAS (km ²) : total surface = 510.1 × 10⁶, oceans = 361.3 × 10⁶, continents and islands
= 148.8 × 10⁶, ice-free land = 133 × 10⁶

MASSES (metric tons) : Earth = 6.0 × 10²¹, oceans = 1.4 × 10¹⁸, ice caps and glaciers
= 2.9 × 10¹⁶, atmosphere = 5.2 × 10¹⁵, lakes and streams = 1.3 × 10¹⁴, living
organisms (wet weight) = 5 × 10¹²

ENERGY FLOWS (kW) : solar energy striking top of atmosphere = 1.72 × 10¹⁴, solar
energy reaching surface = 8.60 × 10¹³, evaporation of water = 4.13 × 10¹³,
gross photosynthesis = 2 × 10¹¹

SEA-LEVEL ATMOSPHERE : mass density = 1.225 kg/m³, pressure = 1.013 bars,
number density = 2.547 × 10¹⁹ molecules/cm³, standard temperature = 15.0°C,
molecular weight of air = 28.96, speed of sound = 331.4 m/sec