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Earth's Systems / Water cycle / Land water: infiltration, runoff and groundwater

Land water: infiltration, runoff and groundwater

What happens to precipitation that reaches land: evapotranspiration back to the air, infiltration into soil and aquifers, slow groundwater flow, and river transport of water, sediment and dissolved nutrients to the sea.

Boundary: where this process starts

Starts with: Rain or snowmelt reaches the ground

Boundary: where it ends

Ends after: Water returns to the air by evapotranspiration; Rivers carry water, sediment and dissolved nutrients to the sea

PARTICIPANTSRESOURCESSoilLand surfaceAquifersRiversPlantsWaterWater vapourSedimentDissolvednutrientsImpact +3 of 5. Click for details and evidence.Impact +3 of 5. Click for details and evidence.Impact +4 of 5. Click for details and evidence.64% evapotranspirationImpact +4 of 5. Click for details and evidence.36% runoff and rechargeImpact 03 of 5. Click for details and evidence.Impact +3 of 5. Click for details and evidence.Impact +3 of 5. Click for details and evidence.Impact +4 of 5. Click for details and evidence.Rain or snowmelt reaches the ground: uses WaterWhat happens to precipitation over land: uses WaterWater returns to the air by evapotranspiration: uses up Wateruses upWater returns to the air by evapotranspiration: makes Water vapourmakesWater soaks into soil, refilling soil moisture and aquifers: uses WaterGroundwater creeps toward rivers and coasts: uses WaterRivers carry water, sediment and dissolved nutrients to the sea: uses WaterRivers carry water, sediment and dissolved nutrients to the sea: uses SedimentRivers carry water, sediment and dissolved nutrients to the sea: uses Dissolved nutrientsinfiltrates or runs offWater: infiltrates or runs offsplit between runoff andinfiltrationWater: split between runoff and infiltrationlost by evaporation andtranspirationWater: lost by evaporation and transpirationreturned to atmosphereWater vapour: returned to atmosphereinfiltrates into soilporesWater: infiltrates into soil poresflows slowly throughaquifersWater: flows slowly through aquiferstransported to coastsWater: transported to coastscarried to the seaSediment: carried to the seadelivered to coastalwatersDissolved nutrients: delivered to coastal watersStart: Land water:infiltration, runoffand groundwaterSTARTStart: Land water: infiltration, runoff and groundwaterEnd: Land water:infiltration, runoffand groundwaterENDEnd: Land water: infiltration, runoff and groundwaterRain or snowmeltreaches the ground📄1Rain or snowmelt reaches the groundWhat happens toprecipitation over land📄1What happens to precipitation over landWater returns to theair byevapotranspiration📄2 ↗1Water returns to the air by evapotranspirationWater soaks into soil,refilling soil moistureand aquifers📄1 ↗1Water soaks into soil, refilling soil moisture and aquifersGroundwater creepstoward rivers andcoasts📄1 ↗1Groundwater creeps toward rivers and coastsRivers carry water,sediment and dissolvednutrients to the sea📄1Rivers carry water, sediment and dissolved nutrients to the sea
Line thickness = size of impact (1 to 5)% on a line = chance a fork takes that branch📄 = pieces of evidence on a stepNegative effectLoops backHypothesisResource used up (arrow into the step)Resource used, not used upResource made or released (arrow out of the step)
What am I looking at? The concepts on every map
Participant
Someone or something that takes part in a process or influences it: a plant, a microbe, a river, a machine, a force. Participants are the rows of a map.
Resource
Something a step uses or uses up: water, oxygen, sunlight, a tool. Each step has an arrow down to the resources it uses.
Step
One thing that happens in a process. Every step has at least one participant and carries evidence.
Decision fork
A step where the process can go several ways. Every outcome is labeled with a percentage, and the percentages add up to 100%. It is not limited to yes or no.
Loop
A line that carries the process back to an earlier step. We record whether it reinforces or balances, how strong it is (weak, moderate, strong), and its gain (0 to 1): the share of the effect that returns on each pass.
Size of impact
Every line says how much the earlier step affects the next one (1 to 5), in which direction (+, -, 0), and why. Thicker lines mean bigger impact.
Evidence
The support for a claim: a source and what it shows. Every step, line, change and vote needs it. Click any step or line to read its evidence.
Boundary
Where a process starts and where it ends. Every process, and every subprocess, has a start and an end.
Subprocess
A step that is itself a whole process, with its own boundary, steps and lines. Click a step marked ↘ to open it. Subprocesses nest as deep as the evidence goes.
Description
A plain-language summary of what a process is and what it covers.
Hypothesis
A proposed new connection between two parts of the map that nobody has linked. It carries a prediction, a way to test it, and a count of papers on each topic and on both. It is an unverified idea until someone tests it.

Every step, with its evidence

The same information as the map, as a list you can search and share. Click a participant or resource to see everywhere it appears.

Rain or snowmelt reaches the ground
Land surfaceVegetationWater
Evidence (1) · added by Atlas
  • Dingman 2015, Physical Hydrology 3rd ed., Waveland Press: Precipitation on land is partitioned into evapotranspiration, surface runoff, interflow and groundwater recharge, with infiltration set by soil structure and vegetation. (confidence 0.75)
⑂ What happens to precipitation over land
Land surfaceSoilPlantsWater
Evidence (1) · added by Atlas
  • Oki & Kanae 2006, Global hydrological cycles and world water resources, Science 313:1068-1072: Global evaporation ~505,000 km3/yr: ~434,000 from ocean (86%) and ~71,000 from land; precipitation ~398,000 on ocean (78%) and ~111,000 on land (22%); ~40,000 km3/yr flows from land to ocean. (confidence 0.9)
Water returns to the air by evapotranspiration
PlantsSoilWaterWater vapour
Evidence (2) · added by Atlas
  • Oki & Kanae 2006, Global hydrological cycles and world water resources, Science 313:1068-1072: Global evaporation ~505,000 km3/yr: ~434,000 from ocean (86%) and ~71,000 from land; precipitation ~398,000 on ocean (78%) and ~111,000 on land (22%); ~40,000 km3/yr flows from land to ocean. (confidence 0.9)
  • van der Ent et al. 2010, Origin and fate of atmospheric moisture over continents, Water Resour. Res. 46:W09525: About 40% of continental precipitation originates from evaporation over land (moisture recycling), so land evapotranspiration feeds later rain. (confidence 0.85)
Water soaks into soil, refilling soil moisture and aquifers
SoilAquifersRootsWater
Evidence (1) · added by Atlas
  • Dingman 2015, Physical Hydrology 3rd ed., Waveland Press: Precipitation on land is partitioned into evapotranspiration, surface runoff, interflow and groundwater recharge, with infiltration set by soil structure and vegetation. (confidence 0.75)
Groundwater creeps toward rivers and coasts
AquifersWater
Evidence (1) · added by Atlas
  • Dingman 2015, Physical Hydrology 3rd ed., Waveland Press: Precipitation on land is partitioned into evapotranspiration, surface runoff, interflow and groundwater recharge, with infiltration set by soil structure and vegetation. (confidence 0.75)
Rivers carry water, sediment and dissolved nutrients to the sea
RiversEstuariesWaterSedimentDissolved nutrients
Evidence (1) · added by Atlas
  • Oki & Kanae 2006, Global hydrological cycles and world water resources, Science 313:1068-1072: Global evaporation ~505,000 km3/yr: ~434,000 from ocean (86%) and ~71,000 from land; precipitation ~398,000 on ocean (78%) and ~111,000 on land (22%); ~40,000 km3/yr flows from land to ocean. (confidence 0.9)