Grade 7 Science
Climate
Chapter 6 Study Guide
Section 1: What is climate?
 An area’s climate is the average weather over a long period of time, such as 30 years
 Features such as bodies of water, ocean currents, mountains, large cities, and latitude
affect climate
 three main climate zones:
o Tropical- warm temperatures because Sun hits directly
o Temperate- mild, moderate temperatures
o Polar- cold temperatures because Sun has low angle
 Why do areas near oceans have mild temperatures in the summer and winter?
 Windward vs. leeward side of mountain
 Why do cities have a warmer climate than the surrounding suburbs?
Key terms: climate, tropics, polar zone, temperate zone
Ocean Currents- NOT IN TEXTBOOK
 Salinity refers to the amount of salt in the ocean
o What does salinity affect?
 Two types of ocean currents:
1. Deep= cold, more dense, and moves slowly
2. Surface – warm, less dense, and moves quickly because affected by wind
 What two ocean currents directly impact the climate of the United States?
Section 3: Climatic Changes
 Seasons are caused by the tilt of Earth’s axis
 During El Niño years, the trade winds are weaker and sometimes reverse
 During La Niña years, the trade winds are stronger
 Temperatures during interglacial intervals vs. ice ages
o We are now in an interglacial interval
 Causes of climate change:
o Volcanic eruptions- cool temperatures on Earth when dust blocks sunlight
o Solar radiation changes
o Earth movements- tilt, axis, and shape of orbit changes
o Plate movements- change position of land/bodies of water
 The greenhouse effect occurs when certain gases trap heat in Earth’s atmosphere
o What are the greenhouse gases?
 Earth’s temperature has increased 0.6°C (or 33°F) the past 100 years
 What are the effects of global warming?
 Humans contribute to global warming by burning fossil fuels and deforestation
o What gas enters the atmosphere when fossil fuels are burned and trees are cut
down/burned?
Key terms: season, El Niño, greenhouse effect, global warming, deforestation
Grade 7 Science
Possible short answer questions:
1. ocean currents
2. natural vs. human climatic changes
Climate