Groundwater and Climate

The Water Cycle Animation During the recycling of water, water enters the atmosphere by evaporation and transpiration of surface water. Of the precipitation that falls on Earth’s surface 50% returns to the atmosphere by evaporation. 18% infiltrates the ground and turns into groundwater. 32% is surface runoff that enters lakes and rivers. The Water Cycle Animation

Groundwater and Precipitation Precipitation brings atmospheric water back to Earth’s surface. Infiltration is the process by which precipitation that has fallen on land trickles into the ground and becomes groundwater.

Why are some areas more prone to flooding? *Infiltration: water enters ground (as ground water) Saturation: all pore spaces in soil are filled with water Water table: boundary between zone of saturation and zone of aeration

Groundwater Storage Zone of Saturation All spaces, cracks and other openings in soil and rock grains become completely filled with water. Water will stop sinking into the soil once it has reached a layer of solid rock that it cannot pass through. The Water Table Boundary between the zone of aeration and the zone of saturation. The Zone of Aeration Materials are moist, but because they are not saturated with water, air occupies most of the space.

Groundwater Movement The amount of water in the ground and the movement of water through the ground are controlled by the characteristics of the soil and rock found near the surface Almost all materials on Earth’s surface are porous.

Porosity Porosity: ratio of free space to occupied space between grains The porosity (percent of empty space) determines how much air or water a sample of rock can hold. If all the particles are similar in size, then the porosity will be high.

Review: Which has a greater porosity? Glacial till or beach sand? Beach sand- because it has more similar particle sizes Glacial till is unsorted and will have less pore space

Permeability Permeability: ability of water to flow through pore spaces or between particles The rate (how fast water can pass through a soil) depends on the size of the pores and how the pores are connected. The bigger the particles, the higher the permeability. Surface runoff occurs when rainfall exceeds the permeability of a soil, when a soil is saturated, or when the slope (gradient) of a soil’s surface is too great to allow infiltration to occur.

Capillarity Capillarity is the ability of a soil to draw water upward into tiny spaces between soil grains. Soils composed of very small particles show the most capillary uptake. For example: Think of a straw! Capillary water moves upward against the force of gravity because of the attraction between water molecules and the surfaces of the soil particles.

http://techalive.mtu.edu/meec/module06/Permeability.htm http://www.eram.k12.ny.us/education/components/docmgr/default.php?sectiondetailid=17500&fileitem=1747&catfilter=447 http://www.83science.com/Topics/Surface%20Processes/Animations/Porosity%20and%20Permeability.swf

DO NOW: Which picture has the most porosity (% of pore space)? A, B, C, and D all have the same porosity. Which picture has the most permeability (water will flow through the fastest)? A is the most permeable. Which picture has the greatest capillarity (water will be taken upward)? D Has the greatest capillarity.

Runoff and Infiltration A number of conditions will determine whether water on Earth’s surface will infiltrate the ground or become runoff. For water to enter the ground, there must be large enough pores or space in the soil and rock to accommodate the water’s volume. Factors of Infiltration – Which is best? Soil made of clay and silt humus Soil made of sand Heavy precipitation Gentle, long-lasting rainfall Soils without much or any vegetation Soils with grasses or other vegetation Soils with gentle slopes Soils with steep slopes a a a a

Long Island Aquifer System Almost all of Long Island’s water is from groundwater. Nassau and Suffolk Counties obtain 375 million gallons per day The largest of Long Island’s aquifers and is composed of sand and clay. Source of water for Nassau and Suffolk. Formed during the last ice age and is composed of glacial till. Aquiclude that separated the Magothy from the Lloyd Aquifers. The deepest and oldest aquifer containing sand and gravel. Not many wells tap into this unit because we may need it in the future. Consolidated bedrock with no water throughout it.

Threats to our Water Supply Changes to groundwater supplies can lead to environmental issues such as lowered water table, subsidence and pollution. Overuse: If groundwater is pumped out faster than it can be recharged, the supply will decrease and the water table will drop. Subsidence: The sinking of the land might occur because groundwater helps support the weight of the soil. Pollution: The biggest and easiest threat that can happen is pollution to our aquifers…

Pollution to Groundwater Some sources of groundwater pollution include: Sewage from faulty septic tanks and farms Landfills Other waste disposal sites Some chemicals can travel through each aquifer layer because they are submicrospic in size.

Protecting Our Water Supply There are a number of ways by which groundwater can be protected and restored. Start by eliminating: Groundwater Pollution Sources Infiltration from fertilizers Drainage of acid from mines Leaks from storage tanks Leaks from waste disposal sites Seepage from faulty septic tanks Radon Saltwater intrusion near shoreline aquifers While these measure can have limited success, they alone cannot save Earth’s water supply. Humans must be aware of how their activities impact the groundwater system so that they can protect the water supply. What can you do?

Stream Systems Precipitation that does not enter the ground usually runs off the surface quickly. As the amount of runoff increases, the channels widen, deepen, and become longer. All of the land area whose water drains into a stream system is called the system’s watershed (or drainage basin). A divide separates one watershed from another.

The Factors that Affect Climate ©Mark Place, 2009-2010 www.LearnEarthScience.com

Identify five factors that affect climate and explain how each affects climate.

Latitude

As latitude ________, the average annual temperature _________. How does latitude affect climate? As latitude ________, the average annual temperature _________. increases decreases Temperature 0° Latitude 90°

Closeness to Large Bodies of Water

                                                                                                                                                                                                                                                                                                                    

Water __________ the temperature. _______ summers. _______ winters. How does closeness to a large body of water affect climate? Water __________ the temperature. _______ summers. _______ winters. moderates Cooler Warmer Cities A & B are located at the same latitude. City B is closer to a large body of water. Its temperature line is flatter (moderated).

Orographic Effect

Orographic Effect

The leeward sides of the Adirondacks & Catskills receive much less precipitation The windward sides of the Adirondacks & Catskills receive a great deal more precipitation

Windward Side: ___________ Leeward Side: _____________ How does the Orographic Effect affect climate? Windward Side: ___________ Leeward Side: _____________ cool, moist warm, dry

Elevation

We live in the troposphere. Temperature decreases Elevation Page 14 of the ESRTs We live in the troposphere. Temperature decreases with elevation.

During summer, temperature is strongly controlled by elevation -- cold at the higher reaches of the Alaska and Brooks Ranges, and warmer in the lowlands.

As elevation _________, the average annual temperature __________. How does elevation affect climate? As elevation _________, the average annual temperature __________. increases decreases Temperature Elevation

Ocean Currents

The Gulf Stream

Warm Currents: warmer climate Cold Currents: cooler climate How do ocean currents affect climate? Warm Currents: warmer climate Cold Currents: cooler climate

How do these winds affect India’s weather in summer and winter? The arrows on the two maps below show how the monsoon winds over India change direction with the seasons. How do these winds affect India’s weather in summer and winter? 1. Summer is cooler and less humid than winter. 2. Summer is warmer and more humid than winter. 3. Winter is warmer and less humid than summer. 4. Winter is cooler and more humid than summer.

Monsoons: Giant Summer Sea Breeze

El Niño Leads to: worldwide change in precipitation patterns High pressure in West Pacific and Low in East Pacific Warmer sea surface temp. in South America Increased storms in South America

Climate Factors 1. Latitude- as latitude increases, temperature decreases (b/c angle of insolation decreases) 2. Elevation/altitude- temperature decreases and precipitation increases 3. Orographic/Mountain Barrier Effect:

4. Proximity to large bodies of water: Marine climates are moderated: -warmer winters and cooler summers -small temperature range Ex. Seattle 5. Planetary wind belts: -NY SW winds 6. Ocean currents: -Gulf Stream- makes us warmer