Factors That Influence & Determine Climate LACEMOPS Factors That Influence & Determine Climate

Weather vs. Climate weather=curr ent atmospheric conditions climate=patt ern of weather over a long period of time for a given location

Learning Goal 3: Describe the physical processes (Earth-Sun relationship) that create climate regions and explain the influence of climate in distribution of plant and animal life. (3A,4AC) Essential Questions Which factors affect an area’s weather over a long period of time? How are the tropical, temperate, and polar climates distributed across the globe? Explain what happens to temperature in higher elevations? How do ocean currents transfer precipitation around the world?

What does LACEMOPS stand for? FACTORS THAT AFFECT CLIMATE

LATITUDE

LATITUDE the most influential factor the farther from the Equator, the colder temps will be sun’s rays hit the earth directly only between (Tropic of Cancer and Tropic of Ca23 ½° N & 23 ½ °S Capricorn, respectively) ; the rest of the earth receives only indirect sunlight three zones: low latitudes (0-23 ½ °N & 0- 23 ½ °S; mid latitudes (Tropics to 66 ½ ° N & S); high latitudes (66 ½ °N & S to the Poles)

AIR MASSES

Air Masses cold air from polar regions; warm air from the tropics

CONTINENTALITY

Continentality Water moderates climate. Water takes LONGER to heat and cool than land. The farther from a large body of water that a location is, the more the temperature will fluctuate. Lands near the ocean do not have such great temp variation as the interiors of continents. For example, Kansas City & San Francisco are located at about the same latitude; KC winters are colder and summers are warmer because KC lies must farther from the ocean’s moderating effects.

Challenge: Where do you think these cities are located on the continent--coastal or Intercontinental?

ELEVATION

ELEVATION Increase in altitude means a decrease in temperature. Every 1000 ft. increase in elevation causes a 3.5°F decrease in temperature. Decrease in temp. caused by lower atmospheric pressure at higher altitudes (short & simple answer).

Lapse Rate -3.5° F for every 1,000 feet you ascend a mountain

MOUNTAIN BARRIERS

Mountain Barriers stop wind & storms also create rain shadow on the leeward side of a mountain range mountains block precipitation so windward side (close to water) gets lots of precipitation, and leeward side (side not close to water) receives very little

OCEAN CURRENTS

Ocean Currents Cold currents bring cold air and move toward the equator. Warm currents bring warm air and move away from the Equator. Warm ocean currents carry warm water from the low latitudes toward the cooler middle latitudes (the Gulf Stream along the US east coast is an example of a warm current). Warm ocean currents warm land areas/cold ocean currents cool land areas. For example, despite its high latitude, the British Isles is moderated by a warm ocean current Because of the earth’s rotation, currents move clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere (The Coriolis Effect).

PRESSURE & PREVAILING WINDS

Pressure & Prevailing Winds High pressure systems are heavy & cold. Low pressure systems are light & warm.

Between 30 ° N and 30 ° S, winds usually blow from the East towards the West. Winds are named for the direction from which they come. Thus this wind is referred to as an easterly wind. These easterly winds are known as the trade winds.

FYI: Trade winds gave rise to the trade routes of the past, & the winds were named accordingly.

Above the subtropical highs in the Northern Hemisphere, and below the subtropical highs in the Southern Hemisphere, winds blow from the West, towards the East. These winds are thus called westerly winds, after the direction from which the winds come.

The subpolar lows generally cause the winds above 60 ° latitude to move from the East towards the West. We call these winds the polar easterlies.

90 polar 40 Tropical 40 polar 90

STORMS

Storms When warm and cold air masses collide, some sort of cyclonic storm, such as hurricanes and typhoons, is the outcome. Northern hemisphere—cyclonic storms spin counter-clockwise Southern hemisphere—cyclonic storms spin clockwise

Which factors affect an area’s weather over a long period of time? How are the tropical, temperate, and polar climates distributed across the globe? Explain what is happening with temperature in higher elevations. How do ocean currents transfer precipitation around the world?

CLIMOGRAPHS The bars represent amount of precipitation received in a given month. The line graph signifies the temperature in a given month. Climate type can be determined by carefully examining climographs. What climate type do you think Guam has?

Reading Climographs to Determine Climate Type In which hemisphere is Guam located, and why does this matter? (island in the Philippine Sea due east of the Philippines; 13°N, 144°E) Does the temperature vary much? Does the area receive much precipitation? If so, are there seasonal differences in the amount of precipitation received? Guam=significant precipitation annually; has a rainy season and a drier season Guam’s climate type=?????