Question of the Day How does water get underground? Subunit: Water and Climate Question of the Day How does water get underground? Does your water come from a reservoir or a well? 130
Water Cycle (Hydrologic Cycle) Fueled by insolation Driven by gravity Recycling of water
What Happens After Precipitation? 1. Water Retention - stored on surface 2. Infiltration - sinks into Earth 3. Runoff - flows over surface 4. Evapotranspiration - recycled into water vapor
Groundwater Water that enters, is stored in, or moves in ground
Groundwater Layers 1. Zone of Aeration Pores (openings) between particles partly filled with capillary water & air
2. Zone of Saturation Pores totally filled with water
3. Water Table Interface between zones of aeration & saturation
Well Water
Groundwater Contamination
Groundwater Contamination
Groundwater Contamination
4. Impermeable Layer No water can infiltrate Ex.: Bedrock, clay
Factors Affecting Infiltration 1. Slope Steeper slope (gradient) = less infiltration
2. Degree of Saturation Greater saturation = less infiltration
3. Porosity Amount of space (pores) between grains Greater porosity = greater ability to hold water
Porosity % of empty space
Factors Affecting Porosity 1. Shape Rounder particles = Greater porosity Angular = Less porosity
2. Packing Well packed = Lower porosity
Porosity Which has more porosity: A or B? A. Because B has tighter packing
3. Sorting (Grouping by size, shape) Sorted (same) = Greater porosity Unsorted (mixed) = Lower porosity
Size Does not affect porosity … … if same shape, sorting, and packing of grains
A B C 1. Draw each set of particles: A,B,C 2. For each set, circle which of each pair has higher porosity A B C
Question of the Day How does water drain in NY State? Can water flow north? 131
Tributary Small stream or river that flows into a larger stream or river
Divide Region of high land that separates 2 drainage systems
Question of the Day How does water move underground? If there is no change in shape, sorting, and packing of these grains, which has higher porosity? 132
Factors Affecting Infiltration 4. Permeability How easily water passes through material Connection between pores, not just volume of pores
Permeability In Loose Material, Size Does Matter! Larger particles, larger pores = More permeable (Ex. gravel, sand) Tighter packing or cementing = Less permeable
Factors Affecting Infiltration Capillarity Attractive force between water and surrounding material
Capillary Water Stored in pores of zone of aeration Important for plants
Capillary Action - Anti-Gravity! Smaller pores = greater capillarity
Runoff occurs when … Precipitation rate > infiltration rate Ground saturated, water hasn’t evaporated Steep slope Little vegetation
Stream Discharge Volume of water flow over time (m³ / second) Time lag between peak precipitation and peak discharge
Flooding Streams/rivers overflow Precipitation rate … > infiltration rate > evapotranspiration rate Storm surge, tsunami, + high tides
Question of the Day What’s the primary factor that affects climate? Q: What’s the difference between weather and climate? 133
Climate Long-term weather conditions Main characteristics: 1. Temperature 2. Precipitation
Latitudinal Climate Zones
1. Latitude Most important factor. Affects temp. & moisture. Average temp. decreases with increasing latitude … due to angle & duration of insolation
A) Latitude & Temperature High latitudes - wide range in temp. Ex. North Pole Low latitudes - small range in temp. Ex. Equator
Fonte Boa, Brazil Nome, Alaska
Planetary wind and pressure belts B) Latitude & Moisture Low press. at 0º & 60º N/S = Wet High press. at 30º N/S & 90º N/S = Dry Planetary wind and pressure belts
Question of the Day What secondary factors affect climate? Where in the world are these cities? B A 134
Syracuse, NY: 43ºN Sydney, Australia: 33ºS
Q: Ireland has the same latitude as northern Canada Q: Ireland has the same latitude as northern Canada. How can they have palm trees???
2. Large Bodies of Water Moderating effect on temperatures - “Oceans = Opposite” Coastal environments - warmer winter, cooler summer
3. Prevailing Winds U.S. - Prevailing S.W. Winds West Coast - Marine Climate East Coast - Continental Climate
Lake Effect Storms Prevailing S.W. bring moisture from Lake Erie to Western NYS
4. Ocean Currents Warm or cool coasts Ex. Ireland has palm trees!
ESRT p, 5
ESRT p, 5
This graph shows avg. monthly temp. for cities A & B This graph shows avg. monthly temp. for cities A & B. Both are located at 41º N latitude.
5. Elevation Higher elev. = Lower temp. Rising air cools & expands Higher elev. = More precipitation Air temp. closer to dewpoint
6. Mountains Orographic Effect Barriers to air masses cause: Orographic Effect Moist climate windward side Warm, dry climate leeward side http://www.pbs.org/wgbh/nova/kilimanjaro/weather.html
Rainshadows and Deserts
7. Vegetation Deforestation - less conversion of insolation through transpiration → higher temp., lower humidity Desertification → higher temp. Urbanization → higher temp.
8. Cloud Cover Cloudier = cooler; insolation reflected
Question of the Day What is a water budget? What’s the difference between a deficit and a surplus? 136
Local Water Budget Mathematical model of water cycle for a region Shows income, outgo and storage Helps identify: Best time to irrigate When flood potential is highest Type of climate: Humid vs. Dry
Budget based on difference between: 1. Precipitation (P) Moisture source 2. Potential Evapotranspiration (Ep or PE) Max. amt. that could evapotranspire
Which city is the most humid? A C B D
Which city is the most arid?
Surplus ● Water supply > Water demand ● Soil moisture storage is full
Usage ● Water taken from storage
Deficit ● Water supply < Water demand ● Soil moisture storage is 0
Recharge ● Water added to storage til saturation
Climate Ratio P Ep 1) Phoenix, AZ P = 191; Ep = 1157 P / Ep = 191 / 1157 = 0.17 Climate: ARID 2) New Orleans, LA P = 1543; Ep = 1118 P / Ep = 1543 / 1118 = 1.4 Climate: Humid