1. Elements of the Water Budget P All the PRECIPITATION that falls in one month

2. Elements of the Water Budget P EPEP All the PRECIPITATION that falls in one month The ENERGY available to evaporate water Potential Evapotranspiration

3. Elements of the Water Budget P EPEP P- E P All the PRECIPITATION that falls in one month The ENERGY available to evaporate water If P-E P > 0, then....If P-E P < 0, then.... There’s water left over There’s energy that can still evaporate more water When water is left over after evaporation, it can do either of 2 things..... Left over energy can “look” for more water.....(where?) Soak into the ground (“infiltrate”) “Run off” in streams In the soil! (called “Storage”)

4. Elements of the Water Budget P EPEP P- E P St  All the PRECIPITATION that falls in one month The ENERGY available to evaporate water If P-E P > 0, then....If P-E P < 0, then.... There’s water left over There’s energy that can still evaporate more water When water is left over after evaporation, it can do either of 2 things..... Left over energy can “look” for more water.....(where?) Soak into the ground (“infiltrate”) “Run off” in streams In the soil! (called “Storage”) Water stored in the Soil (soil moisture) When  St is (+)...When  St is (-)... St E P St >0 and P<E P called “Recharge”called “Usage”

5. Elements of the Water Budget P EPEP P- E P St  EAEA All the PRECIPITATION that falls in one month The ENERGY available to evaporate water If P-E P > 0, then....If P-E P < 0, then.... There’s water left over There’s energy that can still evaporate more water When water is left over after evaporation, it can do either of 2 things..... Left over energy can “look” for more water.....(where?) Soak into the ground (“infiltrate”) “Run off” in streams In the soil! (called “Storage”) Water stored in the Soil (soil moisture) When  St is (+)...When  St is (-)... St E P St >0 and P<E P called “Recharge”called “Usage” Actual amount of water evaporated. E A < E P when E A > E P whenP+ St => E P P + St < E P NEVER! E A = E P when

6. Elements of the Water Budget P EPEP P- E P St  EAEA S D All the PRECIPITATION that falls in one month The ENERGY available to evaporate water If P-E P > 0, then....If P-E P < 0, then.... There’s water left over There’s energy that can still evaporate more water When water is left over after evaporation, it can do either of 2 things..... Left over energy can “look” for more water.....(where?) Soak into the ground (“infiltrate”) “Run off” in streams In the soil! (called “Storage”) Water stored in the Soil (soil moisture) When  St is (+)...When  St is (-)... St E P St >0 and P<E P called “Recharge”called “Usage” Actual amount of water evaporated. E A < E P when E A > E P whenP+ St => E P P + St < E P NEVER! E A = E P when When there’s energy that never finds water, we say we have a.... DEFICIT When there’s more water than energy at the end of the month, we say we have a SURPLUS

7. Elements of the Water Budget P EPEP P- E P St  EAEA S D All the PRECIPITATION that falls in one month The ENERGY available to evaporate water If P-E P > 0, then....If P-E P < 0, then.... There’s water left over There’s energy that can still evaporate more water When water is left over after evaporation, it can do either of 2 things..... Left over energy can “look” for more water.....(where?) Soak into the ground (“infiltrate”) “Run off” in streams In the soil! (called “Storage”) Water stored in the Soil (soil moisture) When  St is (+)...When  St is (-)... St E P St >0 and P<E P called “Recharge”called “Usage” Actual amount of water evaporated. E A < E P when E A > E P whenP+ St => E P P + St < E P NEVER! E A = E P when When there’s energy that never finds water, we say we have a.... DEFICIT When there’s more water than energy at the end of the month, we say we have a SURPLUS

8. INFILTRATION Infiltration refers to water soaking into the ground: Infiltration rate Slope Infiltration rate Permeability Infiltration rate Porosity Infiltration rate Soil Storage Saturation

9. RUNOFF Runoff refers to the water that is not evaporated, and that does not soak into the ground. It is the water we find in streams. Runoff occurs during seasons of highand relatively low In areas where there is a lot of runoff during one part of the year..... and dry and warm during another part of the year..... can be built to store (or reserve) the runoff for an “un-rainy day” P EPEP Rainy season, when there’s extra water When there’s plenty of energy but not enough water to “satisfy” the energy... RESERVOIRS

10. Evaporation Transpiration Animal Respiration runoff infiltration EVAPOTRANSPIRATION The Water (Hydrologic) Cycle -all the ways that water vapor enters the air Condensation