essential elements describe the flow of essential elements from the environment through living organisms and back into the environment. Biogeochemical Cycles

Hydrologic Cycle

How come we never run out of water? ECOWLE C Juvena May Alegre

After four and a half million years you’d think the water would be all used up! It’s not, though, because of one special process: the hydrologic cycle, more commonly called “the Water Cycle.” ECOWLE C Juvena May Alegre

The Hydrological Cycle (also known as the water cycle) is the journey, water takes as it circulates from air, the land, subsurface waters, and organism to the sky, and back again. ECOWLE C Juvena May Alegre

Water is Ubiquitous!

Biosphere- Water Cycle Hydrosphere Liquid waters of earth. 1. Oceans 2. Lakes 3. Streams 4. Glaciers Atmosphere Layer of gases surrounding earth. 1. Clouds 2. Vapor

Earth is a closed system: The water available on Earth, today, is the same water that has always been available and the only water that ever will be available!

How much Water do We Have?

Fresh Water ≤ 1 % of Earth’s water is available for the following : Support organisms such as: plants, bacteria, humans Support industry, agriculture Provide a source of recreation Hydropower plants- energy Transportation Habitats Waste processing

Earth’s Water Budget How the water is divided among: Ocean Land Atmosphere Proportions of water remains relatively stable on Earth. Only the distribution differs (tropical vs desert).

Baby water cycle concept

The elementary water cycle:

Better…

EVEN BETTER, but still lacks time and amount information!(like 90% of clouds are from ocean evaporation)

Water Cycle The actual path any given water molecule follows in a complete water cycle can be varied and complex and may not follow the exact path shown by a diagram.

Water is Always on the Move From Atmosphere to Surface 1. Condensation 2. Precipitation From Surface to Atmosphere 1.Evaporation 2. Transpiration 3. Sublimation Sublimation: from solid to gas without melting. Snow or ice  vapor

What happens to 100 drops of rain fall? 2 make it into our faucets 2 Goes into “ground water” 29 of them go into creeks and rivers 67 drops go back into the sky Within a week

2 make it into our faucets 2 Goes into “ground water” 29 of them go into creeks and rivers 67 drops go back into the sky Within a week But… how do those 67 drops make it back? IN TEXAS..

2 make it into our faucets 2 Goes into “ground water” 29 of them go into creeks and rivers 33 drops evaporate directly 34 drops make it via TRANSPRIATION

Evaporation From liquid to vapor 80% of all water entering the atmosphere originates from the ocean. Transfers energy from the earth’s surface to the air above. Latent energy: hidden heat energy Latere- (Lat.) to lie hidden

Transpiration : The process of transferring water from the roots up to the leaves of the plant to facilitate nutrient transfer. The water is evaporated at the leaves.

Water Vapor Odorless, colorless gas that mixes with other gases in the atmosphere like N 2 and O 2. These gases make up 99% of the atmosphere. The amount of water vapor varies from less than 1% to 4% in the atmosphere.

Condensation Water vapor cools in the upper atmosphere to form drops or ice. Releases latent heat warming the air. The released heat may trigger storms.

Clouds A mass of liquid droplets or frozen crystals. 1. Earth’s water transportation system. in conjunction with wind 2. Determine how much of earth energy is absorbed. block solar rays 3. Alters temperature of air on earth’s surface traps heat on the surface

The process of evaporation and condensation purifies water naturally. Evaporation: only the water molecules leave the surface; the dissolved salts and other solids remain behind in solution. Condensation: when the water vapor condenses again it is pure. It may become contaminated as it falls through the atmosphere: sulfates and nitric oxides ( NOx) cause acid precipitation.

Precipitation Water droplets coalesce to form precipitation. Gravity pulls it to the earths surface. Hail Rain Sleet Snow

Precipitation Interception: falls on leaves or stems of plants. Percolation: moves down into the soil and ground water. Runoff: does not infiltrate soil but travels across the surface of land.

Subsurface Flow – movement of water within the earth, or within aquifers. ECOWLE C Juvena May Alegre

Ground Water Together ground water and soil water make up.5% of freshwater.

Ground Water Zones 1.Unsaturated- soil and water 2.Saturated- ground water Vadose: soil moisture Water table: divides the 2 zones.

Zone of Saturation Aquifer- body of earth material that has the ability to hold and transport water. Unconfined- “open” connected to the surface above. Confined- “closed” sandwiched between dense impermeable layer of earth.

Groundwater Movement Replenished by percolation from zone of aeration downward to zone of saturation. Recharge zone- where confined aquifer is exposed at the surface.

Groundwater flow Seepage: ground water flows to a stream channel, lakes, and wetlands Hydraulic conductivity- the measure of the ability of a material to transport water.

Lets talk TIME for a second How long does it STAY in each place. This is called “residence time” Some places you can guess have LONG residence times – Oceans, lakes, glaciers, groundwater Some places you can then guess have SHORT residence times – Clouds, rivers, soils, animals and plants.

Lets talk SPECIFIC times Reservoir Average residence time of a water molecule Antarctica20,000 years Oceans3,200 years Glaciers20 to 100 years Snow2 to 6 months Soil moisture1 months Groundwater100 – 10,000 years Lakes10 to 100 years Rivers1 to 6 months Atmosphere9 days A single cloud40 minutes

Lets talk Water USES City use Drinking water Sanitation Lawn Car washing Farm use Um.. duh Um.. duh Industry use making energy. making energy. Cooling plants Cooling plants Used in the manufacturing process Used in the manufacturing process

Human Connection United States Family

Effects of Human Activities on Water Cycle We alter the water cycle by: – Withdrawing large amounts of freshwater. – Clearing vegetation and eroding soils. – Polluting surface and underground water. – Contributing to climate change.

Water Issues The amount of water on earth remains constant. World population billion & growing 783 million people do not have access to clean water. 2.5 billion do not have access to adequate sanitation. Demand for food, space, energy and clean water continues to rise. What can you do?