Energy, Temperature & Heat

Energy is defined as the capacity to do work (the amount of work one system is doing on another). There are two kinds of energy that are of interest here: Internal energy is defined as the energy associated with the random, disordered motion of molecules; it refers to the invisible microscopic energy on the atomic […]

Snow as an Insulator: Snow Density

As we just learned, snow is important for global climate because of its role in reflecting solar radiation. But snow and ice are also important because they slow down the escape of heat stored in bodies of water (both oceans and lakes/ponds). Certain characteristics of snow have an important impact on the rate of heat […]

Albedo

Check Your Thinking: How does the capacity of snow and ice to reflect sunlight impact the Earth’s energy budget?   Albedo is a measurement that indicates the amount of reflection of solar radiation by an object. Latin comes into play again here. Albus is Latin for white, which you will recognize from the English word […]

Absorption & Reflection of Energy

Now, let’s think about absorption and reflection in relationship to Earth’s systems and the energy budget. The components of Earth’s systems (air, water, land, and living things) reflect and absorb solar radiation in ways that moderate the global energy budget. A simple activity that you may have done with your students is to place different […]

Earth’s Energy Budget

The balance within the Earth’s systems is largely dependent on a steady flow of energy into and out of each of these systems. Earth’s systems constantly move energy around in cycles (e.g., water cycle, rock cycle, life cycles). The balance of this movement of energy within the Earth’s systems is crucial in maintaining life and […]

Earth’s Systems

It is helpful to think of the Earth as being composed of various large, intricate systems that interact with each other in a manner that keeps things in balance (and, as a result, makes it possible for humans and other organisms to survive on the Earth). Check Your Thinking: Do you know the names of […]

Water Phase Change

A phase change is a change from one state to another without a change in chemical composition. These changes are induced by the effects of temperature and/or pressure: The transitions are: Solid-to-liquid transition – melting Liquid-to-solid transition – freezing Liquid-to-gas transition – evaporation Gas-to-liquid transition – condensation Solid-to-gas transition – sublimation Gas-to-solid transition – deposition […]

Properties of Water

Water can exist in any one of three states: solid (ice), liquid (water), and gas (water vapor). Fresh water has a maximum density at around 4°C: 1 g cm3 (also can be stated as: 1 g ml-1, 1 kg liter-1, 1000 kg m3, or 1 tonne m3). Water is the only substance where the maximum […]

Snowflakes: Symmetry

Snowflakes provide wonderful examples of symmetry. It is useful to engage students in examining symmetry. There are two basic types of symmetry: Rotational symmetry (also known as Radial symmetry) Reflection symmetry (also known as Bilateral, or Mirror symmetry) In rotational symmetry, you can cut the image in half in more than one direction, and the […]

Snowflake Shapes

As you learned in the Snowflake Primer, the shape (morphology) of snowflakes is dependent on climatic conditions. This snow morphology diagram illustrates how temperature and humidity (or supersaturation) affect the shapes of snow crystals. You can engage your students in predicting the shape of snowflakes by collecting data on temperature and humidity whenever it snows, […]