Baikal: the Magic of Water

The lake keeps 80% of Russia's fresh water, or one-fifth of the world's. Probably everybody on Earth knows that this is the planet's largest water depository, but this is not the only remarkable thing about the lake.

The locals remember the legend that says that Baikal has 336 sons and the only daughter named Angara. The sons are the rivers flowing into Baikal. Jan Czerski, a Polish explorer of Siberia, believed there were 336 of them, but recent studies say that there are 544. About 150 of these are seasonal, which means that they only appear in spring when the snow is melting.

Because of its large volume, the water in Baikal is very cold. Even in summer, the upper layers do not get warmer than +8°C. The lake has great heat storage capacity–it stays warm or cold for a long time. This is why in the area around the lake, spring and autumn come from 10 to 15 days later than in places farther away from it. Baikal water is slightly mineralised; it contains about 40 various elements, including sulphur, calcium, magnesium, sodium, potassium, silicon, iron, and phosphorus, but it lacks iodine.  

The water is highly aggressive, and the remains of fish, snails and other animals that end up at the bottom of the lake are fully decomposed. Thanks to active photosynthesis, Baikal water is rich in oxygen. The sun shines above the lake 317 days a year, which is a lot, and the algae are constantly processing carbon dioxide. Because of the low temperatures, the resulting oxygen does not evaporate but stays dissolved in the water.

The water in the lake stays clear thanks to a local endemic, an Epischura baikalensis copepod. It feeds on the algae and other organic matter and filters the water. Furthermore, it is the primary feed of the Baikal omul, another local endemic. A drop of water that enters Baikal stays there for an amazingly long time: 225 years in the North basin, 132 years in the Central basin, and 66 years in the South basin. Over the years, it is filtered by the Epischura copepods, obtains oxygen, freezes and melts again–multiple times. All this makes the water clear as crystal. Another reason why the lake stays clean are its inflowing rivers. 
Baikal has appeared because of tectonic movement and feeds on clean mountain rivers and springs, so the water of the lake is clean as well.

It is important to note that Baikal water is not simply clean–it is incredibly clear as well. You can see the lake's bottom as deep as 40 metres down. 

The best time to try and see the bottom of Baikal is spring when the lake's surface is slightly blue, before algal bloom starts. In summer and autumn, the growing algae make the water less clear, and it becomes greenish. It is especially true for coastal areas where the water is warmer.

It is remarkable that water composition stays consistent throughout different parts of the lake. There are two reasons for that: currents and winds. The currents aren't strong, but they create continuous water circulation. There are three main streams: the southern, the central, and the northern. They are going in circles, counter-clockwise.

There are many winds on Baikal, and nearly each one has its own name. For example, the wind Barguzin blows from the Barguzin Valley and more often than not, brings clear sunny weather. Kultuk is a southwestern wind that, on the opposite, brings clouds and rainfall. Before it comes, the Khamar-Daban mountain range hides in mist.

Sarma is a rough, gusting wind that is extremely swift–up to 60 metres per second. It raves in the middle part of the lake and can float away boats, cattle, and even tear down roofs. Local legends give this wind a personality of an austere, commanding woman who does as she pleases. When Sarma blows, the waves can get 4 to 6 metres high. This is the time when no fisherman goes sailing.