The Dead Sea

Sounds kinda creepy, doesn't it? The name 'Dead Sea' is actually a kinder, gentler translation from the Hebrew name 'Yam ha Maved', which means, 'Killer Sea'. The surface of the Dead Sea is over 1,300 feet below sea level. The very bottom of the sea, in the deepest part, is over 2,300 feet below sea level. The Dead Sea has some of the most saline water on earth; as much as 35% of the water is dissolved salts! The Dead Sea is completely landlocked and it gets saltier with increasing depth. The surface, fed by the River Jordan, is the least saline. Down to about 130 feet (40 meters), the seawater comprises about 300 grams of salt per kilogram of seawater. That's about ten times the salinity of the oceans. Below 300 feet, though, the sea has 332 grams of salt per kilogram of seawater and is saturated. Salt precipitates out and piles up on the bottom of the sea.

There are no fish or any kind of swimming, squirming creatures living in or near the water. There are, however, several types of bacteria and one type of algea that have adapted to harsh life in the waters of the Dead Sea. What you'll see on the shores of the Sea is white, crystals of salt covering EVERYTHING. And this is no ordinary table salt, either. The salts found in the Dead Sea are mineral salts, just like you find in the oceans of the world, only in extreme concentrations. The water in the Dead Sea is deadly to most living things. Fish accidentally swimming into the waters from one of the several freshwater streams that feed the Sea are killed instantly, their bodies quickly coated with a preserving layer of salt crystals and then tossed onto shore by the wind and waves. Brutal!

The guy on top is actually floating in the Dead Sea. "But, hey, I thought you said the Dead Sea was DEADLY!" Not to us. Humans are remarkably adaptable. We can swim in the Dead Sea, just like we can swim in the ocean. Well, people don't really "swim" in the Dead Sea - they just "hang out". That's what's so cool about the Dead Sea. Because of the extremely high concentration of dissolved mineral salts in the water its density is way more than that of plain fresh water. What this means is our bodies are more buoyant in the Dead Sea - so you bob like a cork. In fact, people are so buoyant in this water, it makes it kinda tough to actually swim. Most people like to just kick back in the water and read. It almost looks as though this guy is sitting on an air mattress that has sunk below the surface, but he's not. He's really just floating, without having to hold is feet in that position! If you think this is easy, try floating like this in a freshwater swimming pool.

Why is the Dead Sea so Salty?

We talked about how the surface of the Sea got down so low in elevation, but why is it so salty? All roads lead to the Sea when it comes to the rivers in the area. The Dead Sea is continually fed water from the rivers and streams coming down off the mountains that surround it. But the kicker is this....no rivers drain out of the Dead Sea. The only way water gets out of the Sea is through evaporation. And boy does it evaporate! This part of the world get plenty hot. When the water evaporates, it leaves behind all the dissolved minerals in the Sea, just making it saltier. In fact, it's through the dual action of; 1) continuing evaporation and 2) minerals salts carried into the Sea from the local rivers, that makes the Sea so salty. The fact that the water doesn't escape the Sea just traps the salts within its shores.

Source:http://www.extremescience.com/zoom/index.php/earth-records/37-dead-sea