information:extraction
Cooling

Transpiration serves to evaporatively cool plants, as the evaporating water carries away heat energy due to its large latent heat of vaporization of 2260 kJ per liter.

Transpirational cooling is the cooling provided as plants transpire water. Excess heat generated from solar radiation is damaging to plant cells and thermal injury occurs during drought or when there is rapid transpiration which produces wilting. Green vegetation contributes to moderating climate by being cooler than adjacent bare earth or constructed areas. As plant leaves transpire they use energy to evaporate water aggregating up to a huge volume globally every day.

An individual tree can transpire hundreds of liters of water per day. For every 100 liters of water transpired, the tree then cools by 70 kWh. Urban heat island effects can be attributed to the replacement of vegetation by constructed surfaces. Deforested areas reveal a higher temperature than adjacent intact forest. Forests and other natural ecosystems support climate stabilisation.