DISTRIBUTION OF DISTRIBUTION OF WATER WATER

RESOURCESRESOURCES

Physical Science MW 4:30 – 6:00 pm

Sir John Paul Lesondato

Amazona, Ma. Faye Monette U.Nolasco, Cecille Mae D.Orongan, Patricia Louise U.

DISTRIBUTION OF EARTH’S WATER

HYDROLOGIC CYCLE DIFFERENT PROCESSES

DISTRIBUTION OF DISTRIBUTION OF EARTH’S WATEREARTH’S WATER

The left-side bar shows where the water on Earth exists; about 97 percent of all water is in the oceans. The middle bar shows the distribution of that three percent of all Earth's water that is freshwater. The majority, about 69 percent, is locked up in glaciers and icecaps, mainly in Greenland and Antarctica.

You might be surprised that of the remaining freshwater, almost all of it is below your feet, as ground water. No matter where on Earth you are standing, chances are that, at some depth, the ground below you is saturated with water.

Of all the freshwater on Earth, only about 0.3 percent is contained in rivers and lakes—yet rivers and lakes are not only the water we are most familiar with, it is also where most of the water we use in our everyday lives exists.

HYDROLOGIC CYCLE

Water cycleWater cycle

The The water cyclewater cycle, also known , also known as the as the hydrologic cyclehydrologic cycle or or H2O cycleH2O cycle, describes the , describes the continuous movement of water continuous movement of water on, above and below the surface on, above and below the surface of the Earth. Water can change of the Earth. Water can change states among liquid, vapor, and states among liquid, vapor, and ice at various places in the ice at various places in the water cycle. water cycle.

Although the balance of water Although the balance of water on Earth remains fairly constant on Earth remains fairly constant over time, individual water over time, individual water molecules can come and go. molecules can come and go. Over geologic time, water-rich Over geologic time, water-rich planets such as the Earth lose planets such as the Earth lose gases such as Hydrogen over gases such as Hydrogen over time, which can lead to run away time, which can lead to run away greenhouse effects which in turn greenhouse effects which in turn accelerate Hydrogen loss, and accelerate Hydrogen loss, and by association water loss, from a by association water loss, from a planet's atmosphere.planet's atmosphere.

DescriptionDescription

The sun, which drives the The sun, which drives the water cycle, heats water in oceans water cycle, heats water in oceans and seas. Water evaporates as and seas. Water evaporates as water vapor into the air. Ice and water vapor into the air. Ice and snow can sublimate directly into snow can sublimate directly into water vapor. water vapor.

Evapotranspiration is water Evapotranspiration is water transpired from plants and transpired from plants and evaporated from the soil. evaporated from the soil. Rising air currents take the Rising air currents take the vapor up into the atmosphere vapor up into the atmosphere where cooler temperatures where cooler temperatures cause it to condense into cause it to condense into clouds. clouds.

Air currents move water vapor Air currents move water vapor around the globe, cloud particles around the globe, cloud particles collide, grow, and fall out of the collide, grow, and fall out of the sky as precipitation. Some sky as precipitation. Some precipitation falls as snow or hail, precipitation falls as snow or hail, and can accumulate as ice caps and can accumulate as ice caps and glaciers, which can store and glaciers, which can store frozen water for thousands of frozen water for thousands of years. years.

Snowpacks can thaw and melt, and Snowpacks can thaw and melt, and the melted water flows over land the melted water flows over land as snowmelt. as snowmelt.

Most water falls back into the Most water falls back into the oceans or onto land as rain, where oceans or onto land as rain, where the water flows over the ground as the water flows over the ground as surface runoffsurface runoff. A portion of runoff . A portion of runoff enters rivers in valleys in the enters rivers in valleys in the landscape, with streamflow moving landscape, with streamflow moving water towards the oceans. water towards the oceans.

Runoff and groundwater are stored Runoff and groundwater are stored as freshwater in lakes. Not all as freshwater in lakes. Not all runoff flows into rivers, much of it runoff flows into rivers, much of it soaks into the ground as soaks into the ground as infiltrationinfiltration. Some water infiltrates . Some water infiltrates deep into the ground and deep into the ground and replenishes replenishes aquifersaquifers, which store , which store freshwater for long periods of time. freshwater for long periods of time.

Some infiltration stays close to Some infiltration stays close to the land surface and can seep the land surface and can seep back into surface-water bodies back into surface-water bodies (and the ocean) as groundwater (and the ocean) as groundwater discharge. Some groundwater discharge. Some groundwater finds openings in the land finds openings in the land surface and comes out as surface and comes out as freshwater springs. Over time, freshwater springs. Over time, the water returns to the ocean, the water returns to the ocean, where our water cycle started.where our water cycle started.

Different Different ProcessesProcesses

PrecipitationPrecipitation Condensed water vapor that falls Condensed water vapor that falls

to the Earth's surface . Most to the Earth's surface . Most precipitation occurs as rain, but precipitation occurs as rain, but also includes snow, hail, fog drip, also includes snow, hail, fog drip, graupel, and sleet. Approximately graupel, and sleet. Approximately 505,000 km3 (121,000 cu mi) of 505,000 km3 (121,000 cu mi) of water fall as precipitation each water fall as precipitation each year, 398,000 km3 (95,000 year, 398,000 km3 (95,000 cu mi) of it over the oceans. cu mi) of it over the oceans.

TYPES OF TYPES OF PRECIPITATIONPRECIPITATION

RainRain>sleet- very cold and the rain >sleet- very cold and the rain

water becomes water becomes partly frozen partly frozen because of hail and snow because of hail and snow or or snow and rain that is melting as it snow and rain that is melting as it falls.falls.

>drizzle- are water droplets >drizzle- are water droplets that fall very fine that fall very fine that they hardly that they hardly be noticed and could be be noticed and could be blown blown by gentle wind as they fall.by gentle wind as they fall.

SnowSnow- - frozen water vapor frozen water vapor where the temperature is where the temperature is dropped below freezing point.dropped below freezing point.

HailsHails- it precipitates may be - it precipitates may be in the form of pellet-like in the form of pellet-like masses of ice and snow.masses of ice and snow.**hailstoneshailstones- tiny balls of - tiny balls of alternating layers of snow alternating layers of snow and ice.and ice.

HailstormsHailstorms- when the hails fall.- when the hails fall.

Canopy interceptionCanopy interception The precipitation that is The precipitation that is

intercepted by plant foliage and intercepted by plant foliage and eventually evaporates back to eventually evaporates back to the atmosphere rather than the atmosphere rather than falling to the ground.falling to the ground.

SnowmeltSnowmelt The runoff produced by melting The runoff produced by melting

snow.snow.

RunoffRunoff The variety of ways by which The variety of ways by which

water moves across the land. This water moves across the land. This includes both surface runoff and includes both surface runoff and channel runoff. As it flows, the channel runoff. As it flows, the water may seep into the ground, water may seep into the ground, evaporate into the air, become evaporate into the air, become stored in lakes or reservoirs, or stored in lakes or reservoirs, or be extracted for agricultural or be extracted for agricultural or other human uses.other human uses.

InfiltrationInfiltration The flow of water from the ground The flow of water from the ground

surface into the ground. Once surface into the ground. Once infiltrated, the water becomes soil infiltrated, the water becomes soil moisture or groundwater.moisture or groundwater.

TranspirationTranspiration The release of water vapor from The release of water vapor from

plants and soil into the air. Water plants and soil into the air. Water vapor is a gas that cannot be seen.vapor is a gas that cannot be seen.

Subsurface FlowSubsurface Flow The flow of water underground, in the The flow of water underground, in the

vadose zone and aquifers. Subsurface vadose zone and aquifers. Subsurface water may return to the surface (e.g. as a water may return to the surface (e.g. as a spring or by being pumped) or eventually spring or by being pumped) or eventually seep into the oceans. Water returns to seep into the oceans. Water returns to the land surface at lower elevation than the land surface at lower elevation than where it infiltrated, under the force of where it infiltrated, under the force of gravity or gravity induced pressures. gravity or gravity induced pressures. Groundwater tends to move slowly, and Groundwater tends to move slowly, and is replenished slowly, so it can remain in is replenished slowly, so it can remain in aquifers for thousands of years.aquifers for thousands of years.

EvaporationEvaporation The transformation of water from liquid The transformation of water from liquid

to gas phases as it moves from the to gas phases as it moves from the ground or bodies of water into the ground or bodies of water into the overlying atmosphere. The source of overlying atmosphere. The source of energy for evaporation is primarily solar energy for evaporation is primarily solar radiation. Evaporation often implicitly radiation. Evaporation often implicitly includes includes transpirationtranspiration from plants, from plants, though together they are specifically though together they are specifically referred to as referred to as evapotranspirationevapotranspiration. Total . Total annual evapotranspiration amounts to annual evapotranspiration amounts to approximately 505,000 km3 (121,000 approximately 505,000 km3 (121,000 cu mi) of water, 434,000 km3 (104,000 cu mi) of water, 434,000 km3 (104,000 cu mi) of which evaporates from the cu mi) of which evaporates from the oceans. oceans.

SaturationSaturation a process where the water vapor a process where the water vapor

fills up the air above us. The fills up the air above us. The amount of moisture or vapor amount of moisture or vapor filling the air is called humidity. filling the air is called humidity. It is the direct result of It is the direct result of saturation.saturation.

The evaporation slows down, that The evaporation slows down, that is the time that we feel very is the time that we feel very warm since the sweat from our warm since the sweat from our bodies could no longer vaporize. bodies could no longer vaporize.

SublimationSublimation The state change directly from The state change directly from

solid water (snow or ice) to water solid water (snow or ice) to water vapor. vapor.

AdvectionAdvection The movement of water — in The movement of water — in

solid, liquid, or vapor states — solid, liquid, or vapor states — through the atmosphere. Without through the atmosphere. Without advection, water that evaporated advection, water that evaporated over the oceans could not over the oceans could not precipitate over land. precipitate over land.

CondensationCondensation A process where the enormous A process where the enormous

quantity of particles of water quantity of particles of water vapor which rise up into the vapor which rise up into the atmosphere cools and condenses atmosphere cools and condenses into tiny, little drops of water into tiny, little drops of water which group together to form which group together to form clouds.clouds.

The transformation of water vapor The transformation of water vapor to liquid water droplets in the air, to liquid water droplets in the air, creating clouds and fog.creating clouds and fog.

Condensation on the surface Condensation on the surface

> Dew or Frost> Dew or Frost Condensation near the surfaceCondensation near the surface

>Fog or Smog>Fog or Smog Condensation at High Condensation at High

AltitudesAltitudes

>Stratus, Cumulus, Cirrus >Stratus, Cumulus, Cirrus and Nimbusand Nimbus

THE ENDTHE END

Sources:Sources: http://ga.water.usgs.gov/edu/http://ga.water.usgs.gov/edu/

waterdistribution.htmlwaterdistribution.html http://en.wikipedia.org/wiki/http://en.wikipedia.org/wiki/

Water_cycleWater_cycle