Weather and Climate Chapter 2 section 1

What is weather? Weather- Conditions in one place over a short period of time. Climate- Conditions in one place over a long period of time.

The Greenhouse effect The Earth’s atmosphere traps some of the heat from the sun and reflects it back to Earth much like the glass ceiling of a green house.

Rotation Vs. Revolution Rotation – The spinning of the earth around it’s Axis. Revolution – The movement of the earth around the sun.

Solstices Vs. Equinox Solstice – June 21 and December 21. The days when the sun appears directly above the tropics of Cancer and Capricorn. Summer and winter. Equinox – March 21 and September 23. When the sun is directly over the equator. Vernal (spring) and Autumnal (fall).

Distributing the sun’s Heat The heat of the sun is distributed through convection. Warm gases rise and cooler gases fall. In the air, this process is called wind. In the water, this process is called currents. Due to the rotation of the earth, circular patterns are created called the Coriolis Effect.

Types of Precipitation Precipitation – Water that falls from earth’s atmosphere (Rain) Convectional Precipitation Occurs in warm climates Produces lots of rain which helps to feed lush, tropical rainforests.

Types of Precipitation Orographic Precipitation Warm, moist air is forced upwards over high landforms. As warm ocean air meets mountains, it is forced into cooler air where it condenses and rain or snow falls. The Air is usually dry and cool by the time it reaches the other side of the mountains creating deserts.

Types of Precipitation Frontal Precipitation Occurs when two fronts meet. The warm air is forced upward by the dense cool air. The rising warm air cools and frontal precipitation forms.

Other Influences on Climate Nearby bodies of water Have milder climates since water doesn’t change temperature as much as land does Continental Climates – Inland areas that have more extreme temperature changes between hot and cold. U.S., China, Central Europe and Northern Eurasia. Minnesota can reach -20⁰ F in the Winter and over 100⁰ F in the summer

Other influences on climate Elevation Higher elevation has colder temperatures. That is why there is often snow on the top of mountains.

Other Influences on CLimate Nearby Landforms Mountains, forests, and even cities can affect the temperature and climate of nearby areas.

World Climate Regions The Earth can be broken up into 5 types of climate regions. Tropical Dry Moderate Continental Polar

Changing Climates Through changes in nature and human action, the worlds climates are changing. Many scientists call this change “Global Warming” The earth has cycles of climate change Ice Age Warming Earth’s temperature is rising This creates more extreme weather as the earth tries to balance this out. We are overdue for another ice age.