Gas envelope.
Moves heat, moisture and trace gases through circulation and weather.
Side 38
Earth
Systems
A study of Earth as a coupled system. Atmosphere, oceans, rock, ice, water and life exchange energy and matter across scales, creating cycles, thresholds and feedbacks that cannot be understood one sphere at a time.
sphere→flow→cycle→coupling→feedback
06Earth spheres
05major cycles
06feedback lenses
38Side
Earth is partitioned for study, but not in reality.
Each sphere exchanges matter and energy with the others; the boundaries are analytical conveniences.
Liquid water system.
Oceans, rivers, lakes and groundwater transport heat and dissolved material.
Frozen water.
Ice sheets, glaciers, sea ice and snow influence albedo, sea level and freshwater storage.
Rock and deep Earth.
Crust, mantle and core govern tectonics, volcanism and long-term geochemical cycling.
Living matter.
Life transforms carbon, oxygen, nitrogen, soils and surface energy exchange.
Soil interface.
Soils connect rock, water, air and life while storing nutrients and carbon.
Solar input drives much of the surface system.
Earth absorbs shortwave radiation, redistributes energy and emits longwave radiation back to space.
Incoming
Solar radiation enters.
Latitude, season and orbital geometry shape where energy arrives.
Albedo
Some radiation is reflected.
Clouds, snow, ice, vegetation and surfaces differ in reflectivity.
Absorption
Surface and atmosphere gain energy.
Absorbed energy warms materials and drives phase changes and circulation.
Transport
Atmosphere and ocean redistribute heat.
Circulation moves energy from surplus regions toward deficit regions.
Emission
Earth radiates infrared energy.
Long-run temperature depends on the balance between absorbed solar energy and outgoing infrared radiation.
Matter circulates through reservoirs at different speeds.
Cycles connect biological, chemical and physical processes across seconds to millions of years.
| Cycle | Major reservoirs | Fast process | Slow process |
|---|---|---|---|
| Water | Oceans, ice, atmosphere, groundwater | Evaporation / precipitation | Deep groundwater / ice storage |
| Carbon | Atmosphere, oceans, biomass, rock | Photosynthesis / respiration | Weathering / sedimentation |
| Nitrogen | Atmosphere, soils, biomass | Assimilation / decomposition | Long-term burial |
| Phosphorus | Rock, soils, biomass, sediments | Biological uptake | Rock weathering / burial |
| Rock | Crust and mantle | Erosion / deposition | Metamorphism / melting |
The solid Earth is dynamic.
Plate motion reorganizes continents, ocean basins, mountain belts and volcanic zones over geologic time.
Plates move apart.
New crust forms at spreading centers as mantle material rises and cools.
Plates move together.
Subduction or continental collision drives volcanism, earthquakes and mountain building.
Plates slide past.
Shear accumulates and can release suddenly as earthquakes.
Rock reacts at the surface.
Physical and chemical breakdown feeds soils, sediments and long-term carbon regulation.
Rock is raised into new environments.
Tectonic uplift alters erosion, climate interactions and sediment delivery.
Material moves from depth to surface.
Volcanoes transfer rock and gases between deep Earth and the atmosphere-ocean system.
Climate is a coupled statistical state, not a single weather event.
Long-term patterns emerge from energy balance, circulation, composition, surface conditions and feedbacks.
Atmospheric gases alter outgoing radiation.
Water vapor, carbon dioxide, methane and other gases absorb and emit infrared radiation.
Water stores and transports enormous energy.
Ocean circulation slows and redistributes climate responses.
Less ice can mean more absorption.
Reflective ice loss exposes darker surfaces, amplifying warming locally and regionally.
Warming changes atmospheric moisture.
Warmer air can hold more water vapor, creating an important climate feedback.
Reflect and trap energy.
Cloud feedback depends on altitude, type and distribution.
Particles alter radiation and clouds.
Different aerosols can cool or warm depending on composition and location.
Earth-system change can be gradual, nonlinear or thresholded.
Understanding change requires separating forcing, feedback, internal variability and response timescale.
Forcing
An external influence changes the system’s energy or material balance.
Feedback
The initial change alters processes that amplify or damp the response.
Variability
Internal dynamics create fluctuations even without a new external forcing.
Lag
Large reservoirs such as oceans and ice sheets respond over long timescales.
Threshold
Some components can shift rapidly after a critical condition is crossed.
Recovery
Return paths may differ from departure paths if the system has hysteresis.
Earth System ScienceKump, Kasting & Crane · coupled Earth systems
Global Physical ClimatologyDennis Hartmann · climate dynamics
Understanding EarthGrotzinger & Jordan · geology foundation
BiogeochemistryWilliam Schlesinger · elemental cycles