Description

Learn about fresh water lakes and the different studies conducted on lakes.

Transcript

Learn About the Fresh Water of Lakes Lakes are bodies of water not connected to the ocean. Most contain fresh water which makes them a focus for life as all land the based animals require fresh water to survive. Only 1/3 of 1 % of the earth’s fresh water exist as surface water. Just 3% of the world’s water is fresh but 2/3 being locked away in polar or glacier ice and most of the rest in underground aquifers, two lake systems North America’s Great Lakes and Russia’s lake Baikal account for the more than 50% of the earth’s fresh surface water. Recently, a Russian expedition attempted to send the mini submarine to the bottom of Lake Baikal. Formed in ancient reef valley, Lake Baikal is the deepest body of fresh water in the world and it holds a greater volume of water than any other lake. Organized by the metro pool group in collaboration with the PP Shirshov Institute, to submersibles Mir-1 and Mir-2 were sent down to collect samples of the bed rock at the floor of the lake. The PP Shirshov Institute is part of the Russian Academy of Sciences. It has a fleet of research submersibles designed to function at extreme depths. The Mir craft used for the Baikal dive are capable of descending to 2,000 meters. This was the first time it had been used in fresh water. The dive lasted almost 5 hours in the symbolic gesture, the expeditioners drink a sample of water collected from the bottom, a depth of 1,637 meters. Lake Baikal is a UNESCO world heritage site. During the winter months the lake freezes over with an average ice thickness of one meter, the surface becomes a highway. The Trans Siberian Railway passes along the edge of the lake. Completed in 1914 the railway was indented to open up Russia’s vast Eastern Region but the area is still relatively undeveloped. Situated near the border of Russian Siberia and Mongolia, the lake Baikal region is home to more than 1,700 species of plants and animals most of which are unique to the area. But the region is undergoing changes due to a warming climate. A vast expanse of soil that has been frozen for tens of thousands of years has started to thaw. Huge ice wages have been exposed by the thawing process. The wedges are normally covered by vegetation but as the ice melts, the solid land around it turns into mud and subsides causing trees to fall over and exposing more ice. The thaw is just part of what could be a much greater problem. The frozen soil is known as permafrost as it melts, it releases methane a green house gas but in this case has been trapped in the frozen soil the 20,000 years. The process will accelerate the rate of global warming. Sergei Simov has studied the Siberian Permafrost for over 25 years. He says the melting of the permafrost exposes ancient soil formed during the last ice age when large herbivores like mammoth and bison roamed Siberia. The thaw creates an ever growing number of lakes where methane bubbles up to the surface. Where the natural vegetation of mosses, shrubs and trees has been disturbed the thaw is faster and causes land subsidence. Simov’s research team is trying to find out just how fast this matter is melting, they measure the release of the gases at a test site in the coniferous swamps. To induce the thaw of permafrost they’ve removed the vegetation that normally works as thermal insulation. Ancient organic matter is frozen beneath one million square kilometers of Siberia. It is this ancient compost that is now melting releasing methane and CO2. Humanity emits about 7 billion tons of carbon a year. Simov says permafrost areas hold 500 billion of tons of carbon which if it melts can release methane and carbon dioxide with frightening speed. The methane released as the swampy new lakes continue to grow is 20 times more insulating than CO2 making it a very potent green house agent. In just 10 years, a main road to a goldmine in the neighboring region of Checotah has subsided into an impossible ampi canyon up to seven meters deep in some places. This was the region’s main road. Everyday huge tracks brought cargo over this road but as the permafrost melted the road sank becoming a ravine. The same thing is happening to other roads build above permafrost. Cherski is a depressed town with a population of around 3,000. Here many houses have been demolished or abandoned by tenants after the concrete walls cracked as the ancient ice under their foundations melted. The people of this sparsely populated region depend on fishing for their survival but the thaw is also affecting the fish stocks. Rivers become swollen when the weather warms sometimes bursting their banks and flooding. This is increasing the number and the size of lakes across the region but it interferes with the breeding cycles of the fish and number are declining. Another lake in North Western Italy had the residents of the village of Macanaga worried when H2 was expanding. Lake Ephemeral is fed by melt water from the build of Bilbo de glacier in Italy’s Pier de Bont region and usually causes no problems. But after year of the record breaking heat wave of 2002 run off from the glacier had increased dramatically and civil defense authorities who are using helicopters into six pumps to keep the water level under control. The possibility that it could burst sending 3 million cubic meters of water cascading into Macanaga was very real. During three weeks, the lakes level had raised by a meter a day before a drop in temperatures slowed the rate of melting giving more time for experts to find a solution. A Sonar system was put in place to monitor water levels in Lake Ephimoral around the clock. Occasional bad weather slowed emergency operations already hampered by the lakes location 2,300 meters of above sea level. The camping operation proved effective but the Bilbo de glacier remains diminished.