http://mesothelialcells.us/search/water-cycle-worksheet Topic 8 Water & Climate

Water covers 70% of Earth surface.

Water has been recycled for 3 billion years!

Fueled by solar energy, which causes liquid or solid water to change into a gas, and by gravity pulling water down in the atmosphere, hydrosphere, and lithosphere.

FACTORS AFFECTING INFILTRATION (a.k.a. Seep)

Infiltration is the process by which water on the ground surface enters the soil

Slope of the land The steeper the slope the less infiltration

Degree of saturation The more saturated the ground the less infiltration

Zone of saturation: open spaces filled with water only. Zone of aeration: open spaces filled with air and water. The water table is the interface between the zone of saturation and the zone of aeration.

Porosity: % of open space compared to its total volume The higher the porosity the more the infiltration. Factors that affect porosity: shape, packing, and sorting

Permeability: the ability of material to allow fluids to pass through A material can be porous and yet be impermeable (not permeable) It depends how well the pores (spaces) are connected

Capillarity: water moves up (against gravity) due to the attractive force between water molecules and surrounding particles. The smaller the pore space the greater the capillarity.

Vegetation intercepts precipitation slowing it down which increases infiltration.

Land use: pavement, farming, cutting down trees (deforestation) decreases infiltration.

FACTORS AFFECTING RUNOFF & STREAM DISCHARGE

Stream discharge: is the volume of water that passes a given point in a stream.

Runoff occurs when: It’s precipitation more than the water can infiltrate.

The pore space is already saturated.

The slope of the land is too steep to allow infiltration.

There is water on the surface of the ground. (ex. Puddles)

Runoff often carries water rivers, which carry water to the ocean (completing the cycle).

The greater the runoff the greater the stream discharge The greater the runoff the greater the stream discharge. This is a direct relationship.

FLOODING When a stream overflows.

Precipitation exceeds infiltration.

Hurricane’s storm surge. http://www.weather.com/video/hurricanes-storm-surge-29941 http://abcnews.go.com/US/hurricanes/video/hurricane-irene-storm-surge-moves-beach-building-14397948 http://www.youtube.com/watch?v=cMFKBg3BAPQ

Rising of sea level.

Sinking of the land.

Tides.

Flood Safety http://www.youtube.com/watch?v=7YiB2-yHyuo

Climate Notes

Climate is the overall view of a region’s weather conditions over a long time (100’s of years).

2 major aspects of climate: Temperature (1) The average temperature over a year. (2) Range of average monthly temperatures. Moisture (1) Arid Climate: The annual average precipitation (P) is less than the annual evapotranspiration (Ep). (2) Humid Climate: The annual average precipitation (P) is more than the annual average evapotranspiration (Ep).

1. Latitude and Temperature a. Low latitudes like the Tropics have high angles of insolation and equal duration of insolation (~12 hours each day) therefore there are higher temps and little temperature variation throughout the year.

b. High latitudes like the Poles have low angles of insolation and a variable duration of insolation (0-24 hrs each day) therefore there are lower temps and a wide range temperature variation throughout the year.

2. Latitude and Moisture a. Moisture varies with latitude because of the location of planetary wind and pressure belts.

i. Low pressure (0°, 60°N & S) = lots of precipitation due to air rising, expanding, cooling and condensing. Ex/ tropical rainforest

i. High pressure (30°N & S, 90°N & S) = little precipitation due to air sinking, compressing, warming and evaporating. Ex/ desert Great Victoria Desert 29°S 129°E

Antarctic Desert South Pole = 90°S

3. Large bodies of water a. The climate is moderated by the water’s high specific heat. (Slow heating and cooling.) i. Results in a marine climate. Winters are warmer because the water is still warm from summer and summers are cooler because the water is still cold from winter. Central Canada 23-32°F England 41-50°F

b. Inland areas (areas far from oceans or large lakes) have a continental climate. i. Warm summers and cold winters. Without a large body of water present – the air temperature isn’t moderated. Central Canada 23-32°F England 41-50°F

4. Prevailing winds: a. In the US, the winds are from the Southwest.

b. The winds are caused by pressure differences, unequal heating of Earth’s surface, and the Coriolis effect.

5. Surface ocean currents a. Currents flowing away from the equator carry warm water to high latitudes, while currents from high latitudes carry cool water to the equator.

b. A cool ocean current will cause cooler temps, and less precipitation. (Cold air is more dense so it will not rise.)

c. A warm ocean current will cause warmer temps, and more precipitation. (The warm water will warm up the air – warm air rises creating low pressure = rain.)

6. Elevation a. High altitudes at ANY latitude have cool climates. i. The air rises, expands and cools. ii. Lower amount of greenhouse gases at high altitudes (less air). Huascaran – Peru’s tallest mountain. 9°S 77.6°W

7. Mountains

8. Vegetation a. Arid climate have desert vegetation.

b. Hot, humid climates have tropical rainforest vegetation.

c. Deforestation changes climate – it becomes hotter and less humid due to more run-off and less infiltration.

d. Urbanization: building cities.

9. Cloud cover a. More clouds = cooler temps. (The clouds block the sunlight so that it can’t be absorbed by Earth’s surface and changed into heat.)

b. The equator has lots of thunderstorm clouds (low pressure) so it’s not as hot as at 30°N & S (high pressure) where there isn’t any clouds to block the sunlight.

Climate Change Natural cooling and warming cycles.

Ice Age – during a cooling cycle glaciers advance (grow) from polar regions down towards mid-latitudes.

Global warming – unnatural warming cycle. Greenhouse effect

El Nino http://esminfo.prenhall.com/science/geoanimations/animations/26_NinoNina.html