Why do lakes turnover?
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Most freshwater lakes have zones of temperature according to depth, known as stratification. Have you ever noticed how when you wade into a lake or dive down you encounter a layer of water that is much colder? This is stratification. Fresh water is densest, or heaviest, when it is 39 degrees Fahrenheit.  \n\nDuring late summer the air cools the surface water till it begins to sink, forcing lighter less dense and warmer water to the surface. If at some point all the water in the lake gets to 39 degrees, this temperature-induced mixing will stop, but wind can still force the water to mix. \n\nThis mixing action by wind and cooling is called turnover. \n\nDuring spring, the process reverses itself. Ice melts at the surface. When ice is on the surface of a lake the coldest water is often just under the ice. As this water warms up and becomes the same density and temperature as the deeper water it takes very little wind energy to cause the water to mix, or turnover. As the surface water warms even more, it becomes less dense than the deeper water and forms a stratified layer. After this stratification forms it will remain stratified.
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Deltas and Estuaries are created at the mouths of rivers.\nAnother landform that is created close to the mouth of a river is an ox bow lake.
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The Hydrologic Cycle o Water Cycle\n\nThe hydrologic cycle is a conceptual model that describes the storage and movement of water between the biosphere, atmosphere, lithosphere, and the hydrosphere. Water on this planet can be stored in any one of the following reservoirs: atmosphere, oceans, lakes, rivers, soils, glaciers, snowfields, and groundwater.\n\nWater moves from one reservoir to another by way of processes like evaporation, condensation, precipitation, deposition, runoff, infiltration, sublimation, transpiration, melting, and groundwater flow. The oceans supply most of the evaporated water found in the atmosphere. Of this evaporated water, only 91 % of it is returned to the ocean basins by way of precipitation. The remaining 9 % is transported to areas over landmasses where climatological factors induce the formation of precipitation. The resulting imbalance between rates of evaporation and precipitation over land and ocean is corrected by runoff and groundwater flow to the oceans.\n\nThe planetary water supply is dominated by the oceans. Approximately 97 % of all the water on the Earth is in the oceans. The other 3 % is held as freshwater in glaciers and icecaps, groundwater, lakes, soil, the atmosphere, and within life.\n\nWater is continually cycled between its various reservoirs. This cycling occurs through the processes of evaporation, condensation, precipitation, deposition, runoff, infiltration, sublimation, transpiration, melting, and groundwater flow. On average water is renewed in rivers once every 16 days. Water in the atmosphere is completely replaced once every 8 days. Slower rates of replacement occur in large lakes, glaciers, ocean bodies and groundwater. Replacement in these reservoirs can take from hundreds to thousands of years. Some of these resources (especially groundwater) are being used by humans at rates that far exceed their renewal times. This type of resource use is making this type of water effectively nonrenewable.\n\nALSO CHECK\n\nhttp://www.physicalgeography.net/fundamentals/studyguide_ch8.html
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Elevation is usually the reason.  Especially since water only flows downhill.\n\nI believe it may be that since the river flows into Lake Erie, the "upper" may refer to its source at Walton Lake, or any part of the river before it empties into Sandusky Bay.\n\nSame thing goes for the Nile River.  The Upper Nile is actually in the south and the lower Nile the closer you get into the Mediterranean Sea (going North).\n\nSince the Mississippi flows south, the lower Mississippi is in the southern areas, and the upper Mississippi the closer you get to the Great Lakes.
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A lake is a body of water of varying size that has a stream of water running into it and a stream running out. This keeps the water fresh and the lake at a fairly even depth except for those times of the year when there is heavy snow melt or rain. A pond is a standing pool of water created mostly by run-off water and rain and sometimes a small underground spring. The water evaporates as fast or faster than rain, run-off water or springs can replace it. Ponds become stagnant during hot dry days and sometimes evaporate altogether for a period of time, whereas a lake maintains its stability.
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For most substances, the solid form is denser than the liquid form.  Water is special in that the solid (ice) is less dense than liquid water due to the irregular shape of the crystal, due to the bent shape of the molecule.  THis makes it so that the ice floats on top of the lake, rather than sinking to the bottom.  In this way, the ice actually serve to insulate the lake and prevent the lake from freezing entirely, making the flora and fauna beneath able to survive the winter.
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waves don't always come to shore, they go in most every direction, the reason you see them close to shore is the sloping land under the water makes it apper to get bigger and more pronouced, as it nears the shore. thus making it seem like they always come to the shore.
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It is called continental drift.  Check out wikipedia: http://en.wikipedia.org/wiki/Continental_drift
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B) FALL. The reason is that while the stone is in the boat (or otherwise floating or being supported by a floating object), it is displacing water equal to its WEIGHT, but when fully immersed, it displaces water equal to its VOLUME. This is less water (since if a volume of water equal to the volume of the stone weighed as much or more than the stone, then the stone's density would be less than that of water, which it isn't), and therefore the total water level in the lake will go DOWN.\n\nTo the other answerers: shame on you for not thinking through the problem carefully enough.
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A river levee would form a bank to hold flowing water out of low-lying areas and guide it on a man-made path.  A lake levee would be called an earthen dam or a dike and its purpose would be to collect and hold water in a man-made stationary pool - preventing it from flowing away into areas lower than the desired level of the pool.
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If there were high nitrate levels... the lake would eventually become a wetland or swamp.  Plants like nitrates... aquatic life does not.  Some lakes are suffering from nitrate run-off (it usually comes from farmers fields or where other types of nitrogen rich fertilizers or substances aren't kept in check)  Those nitrates then in turn generate weed growth.  The weed growth will then choke off the lake.  Ever notice the wierd shade of green in a pond next to houses or apartment complexes.  They're using chemicals to keep the water's P-H on the acidic side to curb vegetation and maintain the proper aesthetics that they want of open water.  If you want further information pertaining to your more immediate area... contact your local county agricultural agent.  He or she should be listed in the white pages under county government.
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To sustain life(fauna/flora) on earth especially inland area.\nWater Cycle:\nOcean evaporate > vapour rise to sky > condense form cloud >\nmeet cold front become rain > rain form stream >stream form river > river flow to coast.\nwhen the cycle is disrupt or changed, drought/flood occurs.\nthe site below is an US site for:
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Lake effect snow happens because during the summer, the lake water warms up; then, during the winter, it takes this warm water longer to cool down and freeze.  As a result, there is a period of time where the weather is cold enough for snow, but the lake isn't yet frozen.  As the winds blow over the lake towards the city, it picks up water from the lake and drops it as snow on the city.\n\nBecause the lake usually does freeze, the water is relatively colder in the spring and summer, and cold water evaporates less rapidly than warm water.  So, the air picks up relatively less water from this cold water than it would if the water were warm, so the city is somewhat protected from lake effect "rain".
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Islands are pretty much the peaks of underwater mountains.  They stay above water because they've got more land underwater sitting on the ocean floor.
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Water (rain, snow, dew, ...) which ends up higher than sea level will flow toward the sea if there is any possible path. Since even a mountainous 'bowl' is likely to have a porous bottom, or to fill enough to find an outlet, there will almost always be a flow to lower levels. \n\nFlowing water is not a neglibible force. It will, over geologic time move, dissolve, pulverize, and remove material. Freeze/thaw cycles contribute more than a bit; the Old Stone Face in new Hampshire in N America has recently fallen (literally) to this. Some of that material will be dropped downstream, filling in an existing channel. Spring floods (in places in which snow and ice accumulate on high ground) will provide an annual increase in this erosion, and if they break over channel banks, will accelerate the deposition process (eg, the Nile floods until the installation of dams to stop them). \n\nOver geologic time, a stream (or river) will fill channels repeatedly and will find new flow paths after doing so. What with dumping material from higher levels, and doing it in channels here and there across the gap between highlands, there will be a gradual acretion of soil in that gap. \n\nEventually, the flowing water, combined on occasion with wind and plant and animal soil processing (earthworms, for instance), there will be a more or less level filiing of the gap between highlands, with water flowing across it on the way to the sea. \n\nThat space, with a history more or less as sketched is a valley. Tehy can be narrow (a kilometer or less) or wide (several hundred kilometes). In fact, they can be so wide that it's not possible for a human to see both highlands between which the water flows at the same time. Valleys can also be very long if the highlands are arranged to permit. Consider the Nile, the Danube, the Volga, the Mississippi, or the Ganges. \n\nIn short, highlands erode, flatten out, and fill in the gaps between them. This can be seen in Britain (whose hills and mountains wer once higher) and in the North American Appalacians (whcih were once very very impressively tall). The N American Rockies, S American Andes, and Asian Himalyas are examples of the early stages in this process. Some millions of years hence, all three of these mountain ranges will be much lower and rounder.
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Typically, headwaters only experience recharge, but a local depression in the land surface can create a window into the groundwater, usually in the form of a lake or swamp.  Water here can flow downstream, and thus can add to discharge.
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Unless the land it totally flat, rivers of water run downhill. The vast percentage of rivers on the planet flow in a southerly direction because the source (usually in the mountains) is to the north of the mouth. \nIf the source of a river is at a higher elevation than the mouth, that river will run from the source to the mouth. However, if that (higher) source is to the south of the mouth, that river will then flow to the north (downhill).