Earth System Science Our dynamic planet features several interconnected subsystems that profoundly influence one another. Geosphere Atmosphere Hydrosphere Biosphere

Geosphere Atmosphere Biosphere Hydrosphere 4.6 Billion Years of Interaction

Major Themes Scale Processes in the Earth system act on length scales of microns to thousands of kilometers, and on time scales of milliseconds to millions of years. Energy The Earth system is powered by one external source (the Sun) and two internal ones: radioactive decay, and gravitational energy (heat still being lost from planetary formation). Cycles Material in the Earth system is continually recycled in numerous overlapping cycles.

The Carbon Cycle

The Rock Cycle

The Hydrologic (Water) Cycle

The Biosphere Includes all life. Concentrated near the geosphere surface, from the ocean floor to the lowermost level of the atmosphere.

The Hydrosphere World Ocean ~71% of Earth's surface, ____% of Earth’s water Fresh Water Lakes & Streams Atmosphere Groundwater Glaciers ____% ____% ____% ____% The Hydrologic Cycle Precipitation, Evaporation, Runoff, Infiltration, etc...

The Atmosphere >50% of all air molecules are within 6 km of surface. Air consists mostly of N (78%) and O (21%). Origin: volcanic eruptions, comets, life Predicted surface T of Earth: -18°C (0°F) Actual surface T of Earth: 15°C (60°F) Thank you, greenhouse effect. Thank you, atmosphere.

What is climate? How does climate differ from weather? TIME Weather: Hours to weeks Climate: Months to millenia

What characteristics does a climate have? Air temperature Humidity Precipitation (type & amount) Wind (speed & direction)

Atmospheric Heating Heat is transferred from warmer to cooler hosts. Conduction via molecular activity. Convection via mass vertical movements of a substance. Electromagnetic radiation (300,000 km/sec in a vacuum)

What Affects Air Temperature? (at climatic time scales) Unequal amounts of solar radiation (axial tilt, seasons, etc.) Unequal heating of land & water Altitude (cooler at higher elevations) Geography (esp. regarding winds)

Land vs. Water Land has a lower specific heat than water. (Specific heat: Energy to raise 1 gram of a substance 1°C) Therefore, heats faster than gets hotter than cools faster than LandWater

Elevation Effects

Geographi c effects: Cascade Range blocks moderating coastal winds