CNN 2012-08-24(在线收听

 A lot of stuff we use goes up and down the Mississippi River. We are talking steel, coal, ore, grain. The problem is now a lot of those barges had had to lighten their loads, and even doing that, they are still running aground. There is a real fear that there could be a possibility of closing the Mississippi River.

That`s from a report that Martin Savidge filed on August 10th, the possibility he mentioned is now reality. The U.S. Coast Guard closed down 11 miles of the Mississippi River on Monday. The problem is low water levels, historically low water levels. This is a historic drought combined with extreme heat, and those have combined to drop the level along parts of the Mississippi. Usually around 50 ships a day pass through the area that was closed down on Monday. Officials say the closure has already affected nearly 100 boats and barges.
Diana Nyad is out of the water. 62-year old was making her fourth and possibly last attempt to swim from Cuba to the Florida Keys, but this try, like the others, felt short. Matt Sloane, with the CNN medical unit has been following the story for us. He was in touch with Diana Nyad`s team during her swim. Matt, talk to us about what happened.
Well, Carl, ultimately we know she didn`t succeed in the swim attempt that started 63 hours before she finished up. Just about 40 miles off the coast of Key West. It`s a pretty remarkable fit, no matter how you look at it. Diana actually swam longer in this attempt than she has ever before, even in 1978, she swam only about 41 hours and 42 minutes, this time 41 hours and 45 minutes of actual swimming time. Now, we know she did get out of the water the second night into the swim because of some very bad storms that was actually dangerous for her to continue to stay in the water because of lightning strikes, and jelly fish. You know, the jellyfish have continued to plague her as she does any of these swims, you know she actually had a jellyfish suit on that covered almost all of her body, with the exception of her lips, and jellyfish managed to get the stingers right across her lips and made it very difficult for her to continue swimming. 
One of the other things she is very concerned about, of course, is sharks. She has a device called the shark shield, that`s actually an electronic antenna that goes on a boat that swims right next to her that keeps the sharks away. They don`t like it. It overwhelms their senses. They didn`t see any sharks for most of the swim. Towards the end, they started to get a little bit concerned as the waters got churned up with the storms. A couple of other things that she`s facing that can be very dangerous: sun exposure, dehydration, malnutrition. We know she is burning about 700 calories an hour, she has to replace that somehow. She is now headed back to Key West, she says this will be her last attempt, and she is moving on to bigger and better things. Carl.
This is a very different swim, and a very different body of water. It`s Lake Ontario, one of the Great Lakes. The person you see swimming across it is, Annelise Carr. Nearly 50 other swimmers, including Diana Nyad, have made it across Lake Ontario. But Annelise is the youngest. She is just 14. She took on the challenge to raise money for a childhood cancer center. Annelise said she wanted to accomplish something difficult for kids who fight cancer. According to her parents, Annelise raised close to $80,000. She started the 31.6 mile swim Saturday evening, and 27 hours later, reached the other side.