Why the Aral Sea is dryed?




Environmental Impacts


Water Levels

The primary effect of the Aral Sea desiccation has been the significant loss of water in the sea. The water level has dropped approximately 23 meters since the onset of its primary sources of water being diverted (Zavialov 2005). Although the water level has fluctuated up to a few meters in the past due to natural variability in the water flow from the rivers, by 1970, the water loss exceeded the limit of natural water level variation that has occurred in the past. 

The water budget is determined by several components: Inflow from the river, evaporation, precipitation rates, and groundwater inflow. Net evaporation is defined as the difference between evaporation and precipitation at the surface (Micklin

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Corrientes marinas (in english)




Tipos y causas de las corrientes.




The movement of ocean water is one of the two principal sources of discrepancy between dead reckoned and actual positions of vessels. Water in motion is called a current; the direction toward which it moves is called set, and its speed is called drift. Modern shipping speeds have lessened the impact of currents on a typical voyage, and since electronic navigation allows continuous adjustment of course, there is less need to estimate current set and drift before setting the course to be steered. Nevertheless, a knowledge of ocean currents can be used in cruise planning to reduce transit times, and current models are an integral part of ship routing systems. Oceanographers have

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Famous tidal bores




Title Wave

Famous tidal bores have unique names.

•      aegir (Trent River, England)

•      benak (Batang River, Malaysia)

•      mascaret (Seine River, France)

•      pororoca (Amazon River, Brazil)

•      silver dragon (Qiantang River, China)

A tidal bore occurs along a coast where a river empties into an ocean or sea. A tidal bore is a strong tide that pushes up the river, against the current. A tidal bore is a true tidal wave.

A tidal bore is a surge. A surge is a sudden change in depth. When a channel suddenly gets deeper, it experiences a positive surge. When a channel suddenly gets shallower, it experiences a negative surge. Tidal bores are positive surges.

Not all coasts feature tidal bores. In fact,

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Earth's Inconstant Magnetic Field



Our planet's magnetic field is in a constant state of change, say researchers who are beginning to understand how it behaves and why.

Every few years, scientist Larry Newitt of the Geological Survey of Canada goes hunting. He grabs his gloves, parka, a fancy compass, hops on a plane and flies out over the Canadian arctic. Not much stirs among the scattered islands and sea ice, but Newitt's prey is there--always moving, shifting, elusive.

His quarry is Earth's north magnetic pole.

At the moment it's located in northern Canada, about 600 km from the nearest town: Resolute Bay, population 300, where a popular T-shirt reads "Resolute Bay isn't the end of the world, but you can see it from here." Newitt stops there

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Storms at Sea: A Common Natural Phenomenon


Storm at sea is a very common natural phenomenon that keeps occurring in the sea. We have often seen many paintings by great artists of a storm in the sea. The paintings are powerful and captivating. Have you ever wondered from where these storms occur and what exactly happens behind a sea storm? Well it is a fury of nature that we cannot control.

Today man knows a lot about it and can also predict it to a certain extent. Often alert messages are given in the coastal areas and belts expecting bad weather. The fishermen and the ships on the high sea are told to take extra care and be safe. In spite of all these measures and precautions every year

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