Earth's Energy Balance

Study Notes

Earth's Energy Balance

Overview

Earth's energy balance refers to the balance between the energy the planet receives from the sun and the energy it loses to space.
This balance determines the Earth's climate and temperature.

Energy Sources

Solar radiation: Energy from the sun, which is the primary source of energy for the Earth's climate system.
- Approximately 1366 W/m² of solar radiation reaches the Earth's surface.
Geothermal energy: Heat from the Earth's interior, which is a minor contributor to the energy balance.

Energy Losses

Reflection: A portion of the solar radiation is reflected back into space by the atmosphere and surface.
Atmospheric absorption: The atmosphere absorbs some of the solar radiation, heating the air.
Surface absorption: The surface absorbs the remaining solar radiation, heating the land and oceans.
Infrared radiation: The Earth's surface and atmosphere emit infrared radiation, which is lost to space.
Evaporation and condensation: Energy is lost through the process of evaporation and condensation of water.

Energy Balance Equation

The energy balance can be represented by the equation: Energy In = Energy Out
- Energy In: Solar radiation absorbed by the Earth's surface and atmosphere.
- Energy Out: Energy lost through reflection, atmospheric absorption, surface absorption, infrared radiation, and evaporation/condensation.

Factors Affecting the Energy Balance

Albedo: The Earth's reflectivity, which affects the amount of solar radiation absorbed or reflected.
Greenhouse gases: Increase in greenhouse gases, such as CO2, traps more heat and alters the energy balance.
Volcanic eruptions: Large volcanic eruptions can reduce the amount of solar radiation reaching the surface.
Changes in Earth's orbit: Changes in Earth's orbit can affect the amount of solar radiation the planet receives.

Description

Understand the balance between the energy the Earth receives from the sun and the energy it loses to space, and how it affects the planet's climate and temperature. Learn about the sources of energy, energy losses, and factors that affect the energy balance.