Feb 18, Explanation: The water cycle is the process where water falls as rain, is transported via rivers and streams to lakes and oceans, evaporates into the sky, condenses into clouds, and falls as rain again. Here's a diagram: So what would happen if there were no condensation stage? Without clouds, I foresee a few things happening: From clouds come rain. With no clouds, there would be no rain.
Clouds move moisture from lakes and oceans where it evaporates up to mountains and other places inland that spark rainfall. And so vast stretches of land would become desert. Clouds reflect sunlight and help cool the Earth. With no clouds, the average temperature of the Earth would increase significantly. Related questions What is a biotic factor which would affect the net primary production of a plant? Survey Manual. Earth's water is always in movement, and the natural water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the surface of the Earth.
Water is always changing states between liquid, vapor, and ice, with these processes happening in the blink of an eye and over millions of years. Note: Our information only covers the natural water cycle, which does not take human activities into account. In today's world, humans have a major impact on many components of the water cycle. Download and print this diagram.
Where does all the Earth's water come from? Primordial Earth was an incandescent globe made of magma, but all magmas contain water. Water set free by magma began to cool down the Earth's atmosphere , until it could stay on the surface as a liquid.
Volcanic activity kept and still keeps introducing water in the atmosphere, thus increasing the surface- and groundwater volume of the Earth. 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 groundwater 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 groundwater discharge , and some groundwater 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" For an estimated explanation of where Earth's water exists, look at the chart below. By now, you know that the water cycle describes the movement of Earth's water, so realize that the chart and table below represent the presence of Earth's water at a single point in time.
If you check back in a thousand or million years, no doubt these numbers will be different! Notice how of the world's total water supply of about million cubic miles 1, million cubic kilometers of water, over 96 percent is saline.
And, of the total freshwater, over 68 percent is locked up in ice and glaciers. Another 30 percent of freshwater is in the ground. Thus, rivers and lakes that supply surface water for human uses only constitute about 22, cubic miles 93, cubic kilometers , which is about 0. One estimate of global water distribution Percents are rounded, so will not add to The air is full of water, even if you can't see it. If the water cycle were to stop, lakes, rivers and groundwater sources would dry up, glaciers would disappear and precipitation would stop falling.
All freshwater resources would be negatively impacted, and life on Earth would completely cease. The lack of freshwater would make it impossible to grow food. Foliage would also dry up, causing enormous dust-storms similar to those on Mars. The death of plant life would mark the end of photosynthesis, halting the steady production of oxygen and consumption of excess atmospheric carbon dioxide.
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