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The Water Cycle

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The Water Cycle for Schools. Water cycle - Key Concept - Australian Water Education Toolkit. Condensation - The Water Cycle, from USGS Water-Science School. Clouds over Kiger Notch, Steen's Mountain, OregonCredit: Bureau of Land Management View full size.

Condensation - The Water Cycle, from USGS Water-Science School

The Water Cycle summary, USGS Water Science School. What is the water cycle?

The Water Cycle summary, USGS Water Science School

What is the water cycle? I can easily answer that—it is "me" all over! 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 without it. The Water Cycle. Rain or Snow?: dependent upon temperature. Rain or Snow?

Rain or Snow?: dependent upon temperature

Dependent upon temperature Most precipitation that reaches the ground actually begins as snow high in the atmosphere. These snow flakes develop somewhere above the freezing level where the air temperature is less than 32 F (the dashed blue line), and begin to fall toward the earth as snow. If ground temperature is above 32 F, the freezing level must be located somewhere above the ground. Does Salt Come from Evaporated Sea Water? Seawater contains a variety of salts, and when seawater evaporates, these solids are left behind.

Does Salt Come from Evaporated Sea Water?

The most abundant salt in seawater is sodium chloride (NaCl) which will be referred to in this article simply as salt (technically it is called halite). Layers of salt occur naturally in the geologic record, comprising an abundant source of salt for human consumption worldwide. Today, some salt deposits are land derived, as when salty water seeps from the rocks of Grand Canyon, evaporates and leaves a salty residue. Others are related to enclosed coastal lagoons, which fill up with seawater during a storm, but whose waters are trapped and evaporate between storms.

Thus, salt deposits are classed as evaporites. If a basin of seawater 100 feet thick were to evaporate, only about 2 feet of salt would be left behind. Is fog the same as cloud? - ABC Northern Tasmania - Australian Broadcasting Corporation. Being in a valley, Launceston has the advantage of being sheltered from some of the harsh weather that crosses Tasmania through Winter.

Is fog the same as cloud? - ABC Northern Tasmania - Australian Broadcasting Corporation

It also suffers as a result, with regular Winter fogs settling and becoming trapped under an inversion layer. Rachel McInerney from the Bureau of Meterology explains that fog is really just a low lying cloud, although its definition is determined by its effect on visibility. A fog is present when visibility is reduced to under 1000 metres on the ground. When the fog is warmed by the sun and begins to 'burn off', it can appear as low lying cloud. When there is mid level cloud above it, this can slow that process down, with fog sometimes remaining in the valley until after midday. COW Water Jan2011. Evaporation - National Geographic Society. Evaporation happens when a liquid substance becomes a gas.

evaporation - National Geographic Society

When water is heated, it evaporates. The molecules move and vibrate so quickly that they escape into the atmosphere as molecules of water vapor. Evaporation is a very important part of the water cycle. Heat from the sun, or solar energy, powers the evaporation process. It soaks up moisture from soil in a garden, as well as the biggest oceans and lakes. Although the level of a lake, pool, or glass of water will decrease due to evaporation, the escaped water molecules dont disappear.

Once water evaporates, it also helps form clouds. Many factors affect how evaporation happens. Air pressure also affects evaporation. Temperature, of course, affects how quickly evaporation happens. UCAR Center for Science Education. Clouds are given different names based on their shape and their height in the sky.

UCAR Center for Science Education

Some clouds are near the ground. Others are almost as high as jet planes fly. Some are puffy like cotton. Others are grey and uniform. University of Illinois at Urbana-Champaign. You're right that when the salt is dissolved in liquid water, it really is changed.

University of Illinois at Urbana-Champaign

It falls apart into positively and negatively charged ions. The positive ones (e.g. Na+) tend to be surrounded by contacts to negatively charged parts of water molecules (the oxygen part). The negative ones (e.g. Cl-) tend to be surrounded by contacts to positively charged parts of water molecules (the hydrogen part). When water evaporates, its molecules form a gas, in which they are almost always far apart. The key to understanding this process is to think in terms of physically meaningful quantities like 'energy'. Climate Education Modules for K-12. The water on Earth now is the same water that’s been on Earth since the beginning.

Climate Education Modules for K-12

The rain that falls on us is the same water that rained on the dinosaurs, King Tut, and George Washington. What makes that awesome feat possible?