Unit 5 Weather & Climate B "Exceeds"

Question 1

List and describe the two main processes that have affected the composition of the Earth’s atmosphere over time.

Answer 1

1. Volcanic outgassing is the release of gases such as carbon dioxide, water vapor and other gases into the atmosphere during volcanic eruptions.
2. Photosynthesis – After life evolved cyanobacteria and early plants used carbon dioxide in photosynthesis and released oxygen as a waste product.

Question 2

List and describe the three main types of energy transfer in the troposphere.

Answer 2

1. Radiation – Solar (sun) radiation heats the land and water. Land and water then radiate heat into the troposphere as infrared radiation.
2. Conduction – Heat from land and water transfers to the air just a few centimeters above Earth’s surface by direct contact.
3. Convection – Warm air near the surface expands and rises and cooler denser air sinks, forming convection currents that move heat through the troposphere.

Question 3

Describe the cause of seasonal variation in day length of different latitudes.

Answer 3

Higher latitudes like 70⁰N have greater changes in day length due to the tilt of the Earth’s axis. When a hemisphere is titled away from the sun it receives less daylight causing a decrease in day length.

Question 4

List and define the four types of fronts that form when air masses meet.

Answer 4

1. Cold front – a front that occurs when a cold air mass overtakes a warm air mass.
2. Warm front – a front that occurs when a warm air mass overtakes a cold air mass.
3. Stationary front – a front that occurs when two air masses have formed a boundary but neither is moving.
4. Occluded front – a front that occurs when a warm air mass is caught between two cooler air masses.

Question 5

Describe the rain shadow effect.

Answer 5

When an air mass moves over a mountain range, the air mass rises, cools, and loses most of its moisture through precipitation. As a result, the air that reaches the far side of the mountain range is much drier.