HOW DOES THE LAND- BASED PORTION OF THE HYDROLOGIC CYCLE WORK?

ATMOSPHERE OCEANSCONTINENTS 1,338, ,660 97%2.999% 0.001% 84% 16% 77% 23% -7% +7% Global Runoff 7%

ATMOSPHERE OCEANSCONTINENTS 1,338, ,660 97%2.999% 0.001% 84% 16% 77% 23% -7% +7% Global Runoff 7%

PrecipitationEvaporation Runoff

PrecipitationEvaporation Runoff

SURFACE TENSION Water Surface

SURFACE TENSION Water Surface

SURFACE TENSION Water Surface Weaker attraction Fewer surrounding molecules Stronger attraction Sphere is the shape which has the lowest ratio of surface area (weaker attraction) to volume (stronger attraction). Without other forces water forms spheres

Hydrogen bonding with containing material stronger than bonding between water molecules Hydrogen bonding with containing material weaker than bonding between water molecules

Water “beads” on surface Water “repelled” from surface Capillary Hydrophobic

LEAF

SOIL INTERCEPTION Tree Canopy Shrubs and Bushes Grasses

SOIL Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL Store 1 Input 1 Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL Store 1 Input 1 Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL Store 1 Input 1 Output 1 Input 2 Store 2 Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL Store 1 Input 1 Output 1 Input 2 Store 2 Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL Store 1 Input 1 Output 1 Input 2 Store 2 Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL Store 1 Input 1 Output 1 Input 2 Store 2 Out. 2 Store 3 Input 3 Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL Store 1 Input 1 Output 1 Input 2 Store 2 Output 2 Store 3 Input 3 Out 3 Time into rain storm Rain per unit time Rain reaching soil per unit time

SOIL INTERCEPTION UP TO 20% OF ANNUAL PRECIPITATION SOIL CASCADE OF STORES Store 1 Input 1 Output 1 Input 2 Store 2 Output 2 Store 3 Input 3 Out 3

SOIL INTERCEPTION UP TO 20% OF ANNUAL PRECIPITATION SOIL CASCADE OF STORES Store 1 Input 1 Output 1 Input 2 Store 2 Output 2 Store 3 Input 3 Out 3 DELAYS WATER REACHING SOIL

Precipitation Evaporation Runoff Latent Heat Flux

Precipitation Transpiration Runoff Carbon Dioxide Carbon Dioxide Water Sunlight Photosynthesis

TRANSPIRATION Carbon Dioxide STOMATA Water Stomata open and shut to control diffusion of molecules in and out

Global Vegetation and Oceanic Chlorophyll

Precipitation Evapotranspiration Evaporation and Transpiration Runoff Latent Heat Flux

HUBBARD BROOK Experimental Forest, New Hampshire Source: G. Bonan, Ecological Climatology, Cambridge University Press

Simulation Using Hubbard Brook Characteristics Source: G. Bonan, Ecological Climatology, Cambridge University Press

Average = 1300mm Avg. Dev. = 125 Dev/Avg = 9.6% Average = 800mm Avg. Dev. = 100 Dev/Avg = 12.5% Average = 500mm Avg. Dev. = 25 Dev/Avg = 5%

Source: Bonan, 2008: Ecological Climatology 2012 Forest Fires 2013 Floods Front Ranges, Colorado