Climate Notes

What is Climate?  Climate: Average weather conditions for an area over a long period of time.  Described by average temperatures and average precipitation  Uses monthly and yearly averages

Be Careful!  You can’t use only average temp or average rainfall to predict climate.  Ex: Both San Francisco and St. Louis have the same average yearly temp. but they have very different climates. St. Louis has cold winters and hot summers while SF has mild climate all year long.

SF vs. St. Louis

Factors that Effect Climate  Latitude:  One of the most important factors that influence climate  Areas near the equator receive solar radiation at a 90° angle so it is warmer there.  Areas at the poles are colder because?  Tilt of the Earth’s axis also effects seasons.

Heat Absorption- Land vs Water  Land heats faster than water because it isn’t moving and thus can reach higher temperatures in the same amount of time.  Waves, currents, and other movements continuously replace warm surface water with cooler water from the ocean depths.  In turn, the temperature of the land or ocean influences the amount of heat that the air above the land or ocean absorbs or releases which then effects the climate.

Land vs Water  Where is it cooler during the day, San Francisco or Brentwood?  Where is the air coming from?  Where is it warmer at night, San Francisco or Brentwood?  How is this possible?

Global Wind Patterns- Air Masses  Because Earth receives different amounts of solar energy at different latitudes, belts of cool, dense air form at latitudes near the poles while belts of warm, less dense air form near the equator.  Winds affect many weather conditions, such as precipitation, temperature, and cloud cover.  Thus, regions that have different global wind belts often have different climates.

West Coast vs East Coast  Where does California receive most of its air from? Describe the air.  During the winter where does the air come from in the North East coast of the U.S.? Describe the winters in this area.

Bodies of Water- Ocean Currents  The temperature of ocean currents that come in contact with the air influences the amount of heat absorbed or released by the air.  If winds consistently blow toward shore, ocean currents have a strong effect on air masses over land this effects climate.  Ex: warm Atlantic current mixed with westerlie winds gives NW Europe a high average temperature for it’s latitude.

Why does land heat up faster than water? The temperature of land increases faster than that of water does because the specific heat of land is lower than that of water, and thus the land requires less energy to heat up than the water does.

Topography and Elevation  The surface features of the land, or topography, also influences climate.  The elevation, or height of landforms above sea level, produces distinct temperature changes.  Temperature generally decreases as elevation increases.

Causes for Climate Change  Plate Tectonics:  movement of the continents effects climate  Changes wind flow and ocean currents.  Continents have different climates than they did millions of years ago.

Causes for Climate Change  Human Activity:  Industry  Pollution  Increase in greenhouse gases  Volcanoes:  Sulfur and Ash from eruptions can decrease temperatures which can effect climate.

Climate Zone  Earth has three major types of climate zones: tropical, middle-latitude, and polar.  Each zone has distinct temperature characteristics, including a specific range of temperatures.  Each of these zones has several types of climates because the amount of precipitation within each zone varies.

What are the six climate Regions?  Polar  Continental  Highland  Dry  Tropical  Temperate - California