Module 6 - Greenhouse Gases & Climate Change

The Sun, which is the Earth's only external form of heat, emits solar radiation mainly in the form of short-wave visible and ___________ _________.

ultraviolet (UV) energy

Greenhouse gas

Gases such as carbon dioxide, methane, nitrous oxide, water vapor, and ozone in the atmosphere which are involved in the greenhouse effect.

As this radiation travels toward the Earth, the atmosphere absorbs ___ of it, and ___ is reflected by the clouds back into space. The remaining radiation travels unimpeded to the Earth and heats its surface.

25%, 25%

What makes a molecule a greenhouse gas?

Any gas that has the property of absorbing infrared radiation (net heat energy) emitted from Earth's surface and reradiating it back to Earth's surface, thus contributing to the greenhouse effect. Carbon dioxide, methane, and water vapour are the most important greenhouse gases.

Weather

Includes the daily temperature, humidity, or the amount of precipitation produced by a storm. Weather also includes severe weather conditions such as hurricanes, tornadoes, and blizzards. Because of the dynamic nature of the atmosphere, it is not possible to predict weather conditions in a specific location months or years in advance.

Greenhouse effect

Natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases

Climate vs. weather

Primarily a matter of time and geography. Weather refers to the conditions of the atmosphere over a short period of time, such as hours or days, and typically for a local area. Climate refers to the behavior of the atmosphere over a longer period of time, and usually for a large area.

Climate change

R efers to any significant change in the measures of climate lasting for an extended period of time. In other words, climate change includes major changes in temperature, precipitation, or wind patterns, among others, that occur over several decades or longer. Climate change can occur at the global, continental, regional, and local levels. Climate change may refer to natural changes in climate, or changes caused by human activities.

Global warming

Refers to the recent and ongoing rise in global average temperature near Earth's surface. It is caused mostly by increasing concentrations of greenhouse gases in the atmosphere. Global warming is causing climate patterns to change. However, global warming itself represents only one aspect of climate change.

Why is the greenhouse effect necessary to life on Earth?

This is the Earth's natural greenhouse effect and keeps the Earth 33°C warmer than it would be without an atmosphere, at an average 15°C. In contrast, the moon, which has no atmosphere, has an average surface temperature of -18°C.

Climate

Typically defined based on 30-year averages of weather. Represents our expectations for the weather. Scientists can compare recent and long-term observations of the climate to detect the influence of greenhouse gases on climate conditions.

Greenhouse gases like water vapor, carbon dioxide, methane, and nitrous oxide absorb the...

infrared radiation released by the Earth's surface.

The Earth releases a lot of energy it has received from the Sun back to space. However, the Earth is much cooler than the Sun, so the energy re-emitted from the Earth's surface is much weaker, in the form of...

invisible longwave infrared (IR) radiation, sometimes called heat.