Factors That Influence Weather Mr. Silva Ag Earth Science
Weather and Climate• Weather is caused by movement or transfer of heat energy, which influences temperature, humidity, precipitation, cloud cover, wind speed and wind directions.• Climate describes the total of all weather occurring over a period of years in a given place. – Radiation is how the earth receives solar energy – Conduction is energy transferred by collisions in heat carrying molecules – Convection is energy transferred from hotter to2colder regions of the earth.
Factors that Influence Weather• Air Mass – large body of air that has similar temperature and moisture content – Categorized • equatorial • tropical • polar • arctic • continental • maritime 4
Factors that Influence Weather• Air Pressure – gravity on air mass (99% within 20 miles of Earth’s surface) – measured in millibars, Torr, or hectopascales, or kilopascals (kPa) – low pressure produces stormy weather • (usually) – high pressure produces fair weather • (usually) 5
Factors that Influence Weather• Albedo – is reflectivity. • ocean = low albedo • snow and ice = high albedo • dust = high albedo (solar radiation does not even hit the Earth’s surface) • Critical thinking?? – When has the earth been the coolest? 6
Factors that Influence Weather• Angle of Sunlight – areas closest to the equator receive the most direct angle of sunlight 9
Factors that Influence Weather• Carbon Cycle – The element carbon and molecule carbon dioxide trap and hold heat energy • Consumption of C02 has a cooling effect • Production of C02 has a heating 10 effect
Factors that Influence Weather• Clouds – collections of water droplets or ice crystals that are suspended in air • How? As warmer air rises, it expands due to decreasing pressure, thus drops in temperature = cannot hold as much water vapor. • Vapor condenses forming water particles or ice crystals. 11
Factors that Influence Weather• Distance to Oceans – Oceans are thermally more stable than landmasses. – Changes in temperature are more extreme in the middle of the continents 13
Factors that Influence Weather• Fronts – when two air masses meet, the boundary between them is a front 14
Factors that Influence Weather• Greenhouse Effect – Earth’s ability to trap and contain heat energy • without it life could not exist, too much we burn up 15
Factors that Influence Weather• Heat (Convection) – climate is influenced by how heat energy is exchanged between air over oceans and over land.• Land Changes – climate is influenced by urbanization and deforestation 16
Factors that Influence Weather• Landmass Distribution – Ocean water is much more absorbent than landmasses. Landmasses reflect more solar radiation than land. What does than mean?• Latitude – higher latitudes = less solar radiation• Location – climate is influenced by the location of high and low air pressure zones and where landmasses are distributed 17
Factors that Influence Weather• Moisture Content of Air (Humidity) – this determines plant growth, distribution, and is a major determinant of biome type. • What the hell does that mean? • Where is the most humidity in the world? • Why are there no sprinkler systems in Ohio? 19
Factors that Influence Weather• Mountain Ranges – Mountain effect weather! So, ha! – The ocean facing side (the windward side) will receive more rain. 22
Factors that Influence Weather• Plate Tectonics – climate change through greenhouse effect • How??? We know this. • Short and long term. 23
Factors that Influence Weather• Pollution – greenhouse gases are emitted from both natural and human made sources. • What do greenhouse gases do? • Name three. 24
Factors that Influence Weather• Rotation – Day and night, heat escapes from the Earth’s surface at night. The daily minimum temperature occurs just before sunrise. • So, you will be coldest when you wake up when you are camping. Wear those booties! 25
Factors that Influence Weather• Wind Patterns – Wind patterns are influenced by temperature and pressure differences (gradients) • sun heats atmosphere unevenly • air closest to surface is warmer and rises • high elevations air is cooler and sinks = convection---> primary cause of winds • global air circulation is caused and affected by: – uneven heating of Earth’s surface – seasons – the Coriolis effect – solar radiation 26 – convection cells
Factors that Influence Weather• Human Activity – Deforestation – Urbanization – Release of Pollutants-- greenhouse gases 27
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