Seasons Seasons are determined by two factors: 1.Earths tilt 2.Earths revolution around the sun
Solstice: –Summer marks longest day –Winter marks the shortest day Equinox: –Both day and night are equal all over world –Marks the beginning of spring and fall
Weather Weather: condition of atmosphere at a specific time. Climate: atmospheric condition over a period of time.
Weather Factors 1. cloud cover 2. landforms & bodies of water 3. elevation 4. air movement 5. water vapor Precipitation: falling water in the form of rain or snow (3 types) Convectional- rain forestOrographic- coastalFrontal- great plains
Hurricane/Typhoons Storms that form over warm ocean waters. Take days to develop and are easy to track
Tornados Powerful, funnel shaped, column of spiraling air. Come from powerful thunderstorm. Form quickly with little warning
Blizzards Heavy snow storm with winds of 35+ mph. –Great Lakes area is snowbelt Avg. 37 ½ feet per year.
Droughts A long period of time without rain or minimum rainfall Results in crop failures and reduces levels of water storage. In severe cases can cause famine.
Floods Occur when: –river banks can not hold river water –or the ground becomes saturated during a heavy storm.
Ch. 3.2 “Climate” 5 major factors that influence climate: 1.Wind currents 2.Ocean currents 3.Latitude 4.Elevation 5.Topography
1. Wind Currents Convection: distribution of sun heated atmosphere through the motion of air 2 types of air: 1.Warm air = Low pressure zone 2.Cold air = High pressure zone Transfer of air from H L zones creates wind.
2. Ocean Currents Like rivers in the ocean: –Warm water from the equator to the poles –Cold water from the poles to the equator
3. Zones of Latitude 3 Zones: 1.Low/Tropical 2.Mid/Temperate 3.High/Polar
4. Elevation As altitude increases the temp. drops 3.5 degrees per 1000 ft. Climates above 12,000 ft. become like arctic areas.
5. Topography Landforms like mountains, affect climate Rain shadow is an example:
Changes in Climate Are either due to: 1. Natural Causes 2. Human Activities
El Nino Warming of ocean waters off the west coast of S. America –Pushes warm waters and heavy rains toward Americas ~
Greenhouse Effect Layer of gasses created by the burning of fossil fuels, traps heated air.
Ch. 3.3 “World Climate Regions” Generalizations of typical weather conditions found in certain areas of the earth 2 biggest factors in determining regions: 1.Temp. 2.Precipitation
12 Types of climate: 1. Tropical Wet: –Little temp. variation, typically hot, (around 80 degrees) 2. Tropical wet and dry: –Has both a wet (warm) and dry (cold) seasons 3. Semiarid: –Little precip. about 16 in. per year.
4. Desert: –Categorized by amount of rainfall (lack of moisture), not landforms 5. Mediterranean: –Dry hot summers, winters cool and rainy 6. Marine west coast: –Cloudy, foggy and damp and located close to the ocean 7. Humid subtropical: –Summers hot and humid, winters are mild to cool 8. Humid continental: –Great variety in temp. and precipitation.
9. Subarctic: –Huge temp. variation between summer and winter 10. Tundra: –Flat treeless land almost exclusively in Northern Hemisphere –Permafrost: soil is constantly frozen 11. Ice Cap: –Snow, ice, permanently frozen temp. 12. Highlands: –Climate varies with lat., elevation, topography
Ch. 3.4 “Soils and Vegetation” Soil: weathered rock, humus, air, water that covers the ground Depth, texture, humus content of soil determine the type of vegetation that can be supported –Temp and precipitation also influence
Vegetation Regions Ecosystem: Interdependent community of plants and animals Biome: ecosystem of a region –4 Types of Biomes: 1.Forest 2.Grassland 3.Desert 4.Tundra
1. Forestlands Two Types: 2. Coniferous Needleleaf ie. pine 1.Deciduous Broadleaf ie. cottonwood The Rain forest is located in the tropical zone; covered with broadleaf trees.
2. Grasslands Mostly flat dotted with a few trees. Two types: 1. Savanna 2.Steppe or Praire Northern Hemisphere
3. Desert Characterized by plants that can conserve water and withstand heat like: Cactus Sagebrush
4. Tundra Characterized by plants that tolerate the cold and dry conditions by hugging the ground like: Lichen Moss