Weather & Climate

Weather Weather is the daily temperature, wind speed, & humidity Weather is the daily temperature, wind speed, & humidity An air mass is a large area of air with the same temperature, density, & humidity. An air mass is a large area of air with the same temperature, density, & humidity. Fronts are the boundaries between air masses. Fronts are the boundaries between air masses. Pair share: A point out to B where the fronts meet in the bottom picture.

Three kinds of fronts Stationery Fronts Cold & warm air meet They move side by side along the front Warm Fronts = mild rain Warm air moves slowly up over cold Air cools, forms clouds (cirrus, cumulus) Later rain clouds are formed. Cold Fronts = Severe weather Cold air moves in quickly under warmer air Warmer air is pushed up quickly Thunderstorms, maybe tornadoes

Severe Weather Hurricanes Begin over warm oceans, in late summer Begin over warm oceans, in late summer Energy is released from condensing clouds Energy is released from condensing clouds Extreme low pressure in the “eye” Extreme low pressure in the “eye”

Topography Impacts Weather Mountains cause moist air from oceans to rise, condense, and precipitate On the far side there is a rain shadow ( desert) Pair share: B tell A where you think the rain shadows are in the US? Hint: moist air comes in from the ocean the green represents mountains.

Flat Topography Flat plains of the Midwest do not stop wind flow “Tornado alley”. Tornados: Funnels of high-speed wind Tornados: Funnels of high-speed wind Occur when warm, moist air from Gulf meets cool, dry air from Canada Occur when warm, moist air from Gulf meets cool, dry air from Canada

Why seasons? Earth’s axis is tilted 23.5 degrees In winter, the hemisphere tilts away from sun. In summer, it tilts towards the sun

Climate It’s the average weather of a region Sonoma has a Mediterranean climate Wet, mild winters and dry summers Wet, mild winters and dry summers Rheinland, Germany Napa, CA White board: what is the difference between climate and weather?

Equatorial climate Sun’s rays hitting the equator are more direct Sun’s rays hitting the equator are more direct Climate is hot and wet year-round Climate is hot and wet year-round

Arctic Climate Cold and Dry year round the sun does not sets for 2-3 months of the year and does not rise for another 2-3 months. Ice Hotel, Alaska

Climate change Ice ages have covered most of America in the past. Age of dinosaurs: palm trees in Alaska! Climate will continue to change over time.

Review What happens after a cold front moves in? What causes the seasons? What part of the world has the longest nights?

Summary Main idea Important ideas / topics key facts How the facts relate to the main idea