The Water Recycler

The Water Recycler

Information Guide

Activity 1: Introduction - What if the Earth didn’t Recycle?

1. What do you use fresh water for?

1. Showers/Baths

2. Cooking

3. Cleaning

4. Swimming

5. Washing Cars

6. Watering Lawns

7. Brushing Teeth

8. Drinking

2. How much water do you think you use in one day?

According to the Virginia Polytechnic Institute Water Authority, the average person uses about 125 gallons of water a day. In the United States, 340 billion gallons of water are used every day!

3. How much water do you think is on the Earth?

There's a whole lot of water on Earth! Something like 326,000,000,000,000,000,000 gallons (326 million trillion gallons) of the stuff (roughly 1,260,000,000,000,000,000,000 liters) can be found on our planet.

The total water supply of the world is 326 million cubic miles (a cubic mile is an imaginary cube (a square box) measuring one mile on each side). A cubic mile of water equals more than one trillion gallons.

Estimates vary, but most scientists agree that about 80% of the earth’s surface is covered by water. But very little of that water is available for consumption! Less than 1% of the earth’s water is available for drinking; the rest is found in oceans (97%), in ice and weather systems (2%), and in plants and under the ground (less than 1%).

4. How many gallons of freshwater do you think there is on Earth?

DEMONSTRATION

Water Distribution

• Ocean, Seas, Bays (96.5% of all water)
• Ice caps, Glaciers, & Permanent Snow (1.74% of all water – 68.7% of freshwater)
• Ground Water (1.7% of all water – 30.1% of freshwater).5

5. Complete diagrams

Materials

100 mL clear graduated cylinder

97 mL oil

3 mL water w/ blue food coloring

6. Complete Diagrams

Earth’s Water
Table A / 3.26x1020 gallons
97% Saline / 3.16x1020gallons
3% Fresh / 9.78x1018gallons
Earth’s Fresh Water
Table B / 9.78x1018gallons
68.7% Ice / 6.72x1018gallons
31.3% Obtainable (surface, ground,etc) / 3.06x1018gallons

7. How long would it take the people of the Earth to use up all of the fresh water present on earth?

Assumptions:

What do you think the population of theEarth is?

According to the latest figures from the U.S. Census Bureau, world population reached 5.9 billion people in 1998.This represents more than a doubling of world population since its 1950 level of 2.6 billion people in 1950.

295,203,830 (nearly 300 million!) in the United States

Approximately 1,979,202 people in Cincinnati alone

• Currently there are 5.9 billion people on Earth [5.9x109people]
• Each person uses 125 gallons per day[125 gallons/day]
• The Earth only has 3.06x1018 gallons of freshwateravailable for human consumption [3.06x1018 gallons]

Step 1: Calculate how many gallons the current population of Earth uses in one day

Each day, the people of Earth use 7.4x1011 gallons of water each day.

Step 2: Calculate how long the earth’s fresh water supply will last

The earth would run out of fresh water in approximately 11,000 yrs if the population remains constant and if everyone uses the same amount of water.

8. Why doesn’t the Earth run out of water?

The Earth recycles its water!

-The Water Cycle

-The Hydrologic Cycle

-Reuse of Water

-Water Filtration

Activity 2: The Water ReCycler

All of the information for this activity was taken from the USGS

What is the water cycle?

a.k.a. hydraulic cycle: the circulation(recycling) of water through the biosphere

biosphere: part of the earth where there are living organisms.

What is the water cycle? The water cycle describes the existence and movement of water on, in, and above the Earth. Earth's water is always in movement and is always changing states, from liquid to vapor to ice and back again. The water cycle has been working for billions of years and all life on Earth depends on it continuing to work; the Earth would be a pretty stale place to live without it.

A quick summary of the water cycle

The water cycle has no starting point. But, we'll begin in the oceans, since that is where most of Earth's water exists. The sun, which drives the water cycle, heats water in the oceans. Some of it evaporates as vapor into the air. Ice and snow can sublimate directly into water vapor. Rising air currents take the vapor up into the atmosphere, along with water from evapotranspiration, which is water transpired from plants and evaporated from the soil. The vapor rises into the air where cooler temperatures cause it to condense into clouds. Air currents move clouds around the globe, cloud particles collide, grow, and fall out of the sky as precipitation. Some precipitation falls as snow and can accumulate as ice caps and glaciers, which can store frozen water for thousands of years. Snowpacks in warmer climates often thaw and melt when spring arrives, and the melted water flows overland as snowmelt. Most precipitation falls back into the oceans or onto land, where, due to gravity, the precipitation flows over the ground as surface runoff. A portion of runoff enters rivers in valleys in the landscape, with streamflow moving water towards the oceans. Runoff, and ground-water seepage, accumulate and are stored as freshwater in lakes. Not all runoff flows into rivers, though. Much of it soaks into the ground as infiltration. Some water infiltrates deep into the ground and replenishes aquifers (saturated subsurface rock), which store huge amounts of freshwater for long periods of time. Some infiltration stays close to the land surface and can seep back into surface-water bodies (and the ocean) as ground-water discharge, and some ground water finds openings in the land surface and emerges as freshwater springs. Over time, though, all of this water keeps moving, some to reenter the ocean, where the water cycle "ends" ... oops - I mean, where it "begins."

Components of the water cycle

The U.S. Geological Survey (USGS) has identified 16 components of the water cycle:

Water storage in oceans: 97.6% of all water on Earth is stored in the oceans. Oceans supply 90% of the evaporated water that goes into the water cycle.

Evaporation: Evaporation is the process by which water changes from a liquid to a gas or vapor. (Liquid changing to Gas)

Studies have shown that the oceans, seas, lakes, and rivers provide nearly 90 percent of the moisture in our atmosphere via evaporation, with the remaining 10 percent being contributed by plant transpiration.

Heat (energy) is necessary for evaporation to occur. Energy is used to break the bonds that hold water molecules together, which is why water easily evaporates at the boiling point (212° F, 100° C) but evaporates much more slowly at the freezing point.

Once evaporated, a water molecule spends about 10 days in the air.

Evapotranspiration: the water lost to the atmosphere from the ground surface and the transpiration of groundwater by plants through their leaves.

Transpiration: The release of water from plant leaves

Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves. It is estimated that about 10 percent of the moisture found in the atmosphere is released by plants through transpiration.
Sublimation: the process of snow and ice changing into water vapor without first melting into water

(Solid changing to Gas)

Ex. "Dry ice" is solid, frozen carbon dioxide, which sublimates, or turns to gas, at the temperature -78.5 °C (-109.3°F). The fog you see in the picture is a mixture of cold carbon dioxide gas and cold, humid air, created as the dry ice sublimates.

One place on Earth where sublimation happens a lot, I might choose the south side of Mt.Everest. Low temperatures, strong winds, intense sunlight, very low air pressure - just what is needed for sublimation to occur.

Sublimation Demonstration

What's Dry Ice?

Dry ice is frozen Carbon Dioxide, or CO2, which is a gas under standard temperature and pressure conditions. The atmosphere contains about .035% of this gas. CO2 is a greenhouse gas, which means it absorbs light at infrared wavelengths. An increase in the concentration of this gas would, some scientists believe, cause an increase in the atmosphere's average temperature. The high concentration of CO2 in the atmosphere of the planet Venus is said to contribute to that planet's high average temperature.

At normal atmospheric pressure on this planet, frozen CO2 doesn't melt into a liquid, but rather evaporates directly into its gaseous form. Hence the name dry ice. This process is called sublimation. All of the experiments below rely on this property of dry ice.

Getting Dry Ice

Dry ice is commonly available from ice dealers in two forms: flat square slabs a few inches thick and about eight inches on a side; or cylinders about half an inch in diameter and from a half to 2 ½ inches long. The price for ten pounds is around six dollars. If you buy less than this you will pay about a dollar per pound.

Storing and Transporting Dry Ice

Dry ice continuously sublimates as heat enters it from its surroundings. The CO2 gas that evolves must be vented from the container. Do not seal dry ice into a container except as detailed below, because an explosive bursting of the container can result. A Styrofoam (polystyrene foam) ice chest with a loose fitting lid makes a good container for transporting dry ice.

Handling Dry Ice

Due to its extremely cold temperature (-78.5oC, or -109.3oF), dry ice can cause damage to the skin if handled. Use tongs or insulating gloves when handling dry ice. It is also important when crushing or grinding the solid not to get any of the dust into your eyes. Wear protective goggles.

Popping Film Cans

A fun (and often wild) activity vividly demonstrates the sublimation process. Place a piece of dry ice into a plastic 35mm film container - the kind that has the snap - on cap. Then wait. The cap will pop off, and sometimes fly several meters. The clear Fuji brand containers shoot farther than the gray and black Kodak type. Warn anyone performing this experiment not to aim for anyone's eyes.

Inflate A Balloon

Grab an uninflated balloon and force the neck open with the index and middle fingers of both hands, stretching the balloon open. This will allow you to drop in one or more pellets of dry ice. Tie the balloon closed. Set aside, and observe for awhile. Better yet, drop the balloon into a pond or swimming pool. This will help supply heat to the dry ice. At first, the balloon will sink, but soon, as it begins to inflate, it will rise to the surface.

If you manage to put enough dry ice into the balloon, it will eventually reach the bursting point. Again, this is lots of fun if the balloon is in a pool.

Singing Spoon

Press a warm spoon firmly against a chunk of dry ice. The spoon will scream loudly as the heat of the spoon causes the dry ice to instantly turn to gas where the two make contact. The pressure of this gas pushes the spoon away from the dry ice, and without contact, the dry ice stops sublimating. The spoon falls back into contact again, and the cycle repeats. This all happens so quickly that the spoon vibrates, causing the singing sound you hear.

Fog Effects

When you place dry ice into some warm or hot water, clouds of white fog are created. This white fog is not the CO2 gas, but rather it is condensed water vapor, mixed in with the invisible CO2. The extreme cold causes the water vapor to condense into clouds. The fog is heavy, being carried by the CO2, and will settle to the bottom of a container, and can be poured. You can produce enough ground - hugging fog to fill a medium sized room with a pound or so of dry ice. Do not allow anyone to lay down in this fog, or allow babies or pets into it, as CO2 gas does not support life. Dry ice fog allows low powered laser beams to be seen; see the laser experiments page for details.

Water in the atmosphere: Although the atmosphere may not be a great storehouse of water, it is the superhighway used to move water around the globe. There is always water in the atmosphere. Clouds are, of course, the most visible manifestation of atmospheric water, but even clear air contains water—water in particles that are too small to be seen.

If all of the water in the atmosphere rained down at once, it would only cover the ground to a depth of 2.5 centimeters, about 1 inch.

Condensation: process in which water vapor in the air is changed into liquid water. (Gas changing into a Liquid)

Condensation is crucial to the water cycle because it is responsible for the formation of clouds. These clouds may produce precipitation, which is the primary route for water to return to the Earth's surface within the water cycle.

Condensation is the opposite of evaporation.

Ex. Condensation is responsible for ground-level fog, for your glasses fogging up when you go from a cold room to the outdoors on a hot, humid day, for the water that drips off the outside of your glass of iced tea, and for the water on the inside of your home windows on a cold day.

Precipitation: water released from clouds in the form of rain, freezing rain, sleet, snow, or hail. It is the primary connection in the water cycle that provides for the delivery of atmospheric water to the Earth. Most precipitation falls as rain.

Water storage in ice and snow: much more water is in storage at any one time than is actually moving through the cycle. By storage, we mean water that is locked up in its present state for a relatively long period of time, such as in ice caps and glaciers.

The vast majority, almost 90 percent, of Earth's ice mass is in Antarctica, while the Greenland ice cap contains 10 percent of the total global ice-mass.

Some glacier and ice cap facts

• Glacial ice covers 10 - 11 percent of all land.
• According to the National Snow and Ice Data Center (NSIDC), if all glaciers melted today the seas would rise about 230 feet (70 meters).
• During the last ice age (when glaciers covered more land area than today) the sea level was about 400 feet (122 meters) lower than it is today. At that time, glaciers covered almost one-third of the land.
• During the last warm spell, 125,000 years ago, the seas were about 18 feet (5.5 meters) higher than they are today. About three million years ago the seas could have been up to 165 feet (50.3 meters) higher.

Snowmelt runoff to streams: The effect of snowmelt on potential flooding, mainly during the spring, is something that causes concern for many people around the world. Besides flooding, rapid snowmelt can trigger landslides and debris flows.
Surface runoff: Precipitation runoff which travels over the soil surface to the nearest stream channel

Only about a third of the precipitation that falls over land runs off into streams and rivers and is returned to the oceans. The other two-thirds is evaporated, transpired, or soaks into ground water. Surface runoff can also be diverted by humans for their own uses.
Streamflow: the amount of water flowing in a river
Freshwater storage: Surface water includes the streams (of all sizes, from large rivers to small creeks), ponds, lakes, reservoirs (man-made lakes), and freshwater wetlands. The definition of freshwater is water containing less than 1,000 milligrams per liter of dissolved solids, most often salt.

Freshwater represents only about three percent of all water on Earth and freshwater lakes and swamps account for a mere 0.29 percent of the Earth's freshwater. Twenty percent of all freshwater is in one lake, LakeBaikal in Asia. Another twenty percent is stored in the Great Lakes (Huron, Michigan, and Superior). Rivers hold only about 0.006 percent of total freshwater reserves. You can see that life on Earth survives on what is essentially only a "drop in the bucket" of Earth's total water supply!
Infiltration: The downward movement of water from the land surface into soil or porous rock

Some water that infiltrates will remain in the shallow soil layer, where it will gradually move vertically and horizontally through the soil and subsurface material. Eventually it might enter a stream by seepage into the stream bank. Some of the water may infiltrate deeper, recharging ground-water aquifers. If the aquifers are porous enough to allow water to move freely through it, people can drill wells into the aquifer and use the water for their purposes. Water may travel long distances or remain in ground-water storage for long periods before returning to the surface or seeping into other water bodies, such as streams and the oceans.