Energy Balance and Obesity, Healthy Weight Basics, NHLBI, NIH
Energy transferred due to temperature difference between system and surroundings . Celsius. - 0). • This is based on the assumption that the energy content of Note: Once mass and energy balance equations are written, make sure that the. Energy balance is simply the relationship between your energy input and your energy output. The complete energy equation looks like this. There is a balance between this warming and cooling that determines the allows you to try some "what if" scenarios with our planet's energy balance. The equations dynamically update as you change the albedo and brightness values. Use the popup menu beneath the thermometer to switch between Celsius.
If q is negative, then the reaction is exothermic, that is, heat is given off to the external surroundings. You might also remember the terms kinetic energy and potential energy.
Global Energy Balance
Kinetic energy is the energy of motion -- the amount of energy in an object that is moving. Potential energy is stationary, stored energy.
If you think of a ball sitting on the edge of a table, it has potential energy in the energy possible if it falls off the table. Potential energy can be transformed into kinetic energy if and when the ball actually rolls off the table and is in motion. The total energy of the system is defined as the sum of kinetic and potential energies.
In descriptions of the energy of a system, you will also see the phrase "state properties". A state property is a quantity whose value is independent of the past history of the substance. Typical state properties are altitude, pressure, volume, temperature, and internal energy.
Enthalpy Enthalpy is an interesting concept: A state property, the word enthalpy comes from the Greek "heat inside". Bright surfaces like snow have a high albedo. Forested regions are darker.
How would Earth's temperature change if the albedo was higher or lower? The slider on the left controls the brightness of the Sun. How would Earth's temperature change if the Sun was brighter or dimmer?
Earth's Energy Balance | UCAR Center for Science Education
This model has one extreme simplification - it assumes Earth has no atmosphere! That makes for simpler math, but is clearly unrealistic.
- Chemical Thermodynamics
- Earth's Energy Balance
Earth's atmosphere acts as a blanketmaking our planet habitable. Without the heat-trapping greenhouse gases in our atmosphere, Earth would be a frozen ball of ice!
More Things to Try Use the "Pick a surface Click the "Show Math" button to display the calculations used in this simulation.
Balance Food and Activity
The equations dynamically update as you change the albedo and brightness values. Use the popup menu beneath the brightness slider to switch between settings in terms of the Sun's current brightness percent or in units of watts per square meter. Use the popup menu beneath the thermometer to switch between Celsius, Fahrenheit and Kelvin temperature scales.