| A | B |
|---|
| evapotranspiration | the combination of evaporation and transpiration |
| condensation | the change of water vapor into (liquid or solid) clouds |
| precipitation | any form of water falling from the sky and reaching the earth |
| runoff | in the water budget, SURPLUS water that cannot infiltrate into the soil |
| capillarity | the ability of soil to draw water upward into tiny pore spaces |
| zone of aeration | the portion of the soil above the water table in which the interconnected pores are filled with air |
| zone of saturation | the portion of the soil below the water table in which the pores are filled with ground water |
| regolith | the loose material (soil) at the earth surface |
| permeability | the ability of a soil to allow water to pass thru it |
| porosity | the percentage of empty space within the soil |
| water retention | water which stays (is retained) in the zone of aeration as capillary water |
| water table | the top of the zone of saturation |
| infiltration | water seeping into the ground |
| ground water | water that infiltrates the ground, moves into zone of saturation |
| moisture usage | water from storage that is used for evapotranspiration occurring when P is less than PE and St>0 |
| moisture recharge | within the water budget: infiltrating water that enters storage occurring when P>PE and St<100 |
| moisture surplus | within the water budget: extra water that becomes runoff occurring when P>PE and St=100 (maximum) |
| moisture deficit | within the water budget: shortage of water occurring when P is less than PE and St=0 |
| climate | the condition of the atmosphere over a long period of time |
| continental climate | climate with cooler winters and warmer summers (larger yearly temperature variations) |
| marine climate | climate with cooler summers and warmer winters (smaller yearly temperature variations) |
| arid climate | climate with a P/PE ratio less than 0.4 |
| semiarid climate | climate with a P/PE ratio of 0.4 to 0.8 |
| subhumid climate | climate with a P/PE ratio of 0.8 to 1.2 |
| humid climate | climate with a P/PE ratio greater than 1.2 |
