Lake Vostok (click here) in Antarctica has been in place since it's first discovery in 1959. It is actually 1600 feet below sea level. It is closed off to the Circumpolar Ocean (The East and West Wind Drifts) surrounding Antarctica. The distinctive feature of Lake Vostok is the smooth as glass appearance at the top of the ice. The ice in Antarctica flows. Regardless, of it's movement the section moving over the lake always remains without a ripple. Lake Vostok is liquid because of the pressure of the ice above it which includes 3769 meters. It has the purest water in the world.
When the Russians reached the lake they were met with enormous pressure that refroze the drill hole. The reports of life in that lake begins with this:
July 8, 2013
By Becky Oskin
Microbes (click here) that live inside fish intestines are among the array of life that appear to have been found in ice drilled from above Lake Vostok, the deepest lake buried beneath Antarctica's ice sheet....
The issue with Greenland is very different. There are innumerable entries about the Greenland ice on this blog. NASA takes pictures regularly and measures what is called 'the meander' of the glacier. Greenland Ice, like Antarctica, sits a top land and it's base is frozen into those dips in the landscape, but, every Spring with top melt water from the sun, there is a hydraulic effect and the glacier floats and meanders over the land.
If there are glacial lakes under the Greenland Ice, it is not due to pressure of the ice above so much as the hydraulic effect of the melt water. The water mass is probably greater this Spring than any other. Greenland Melt Extent (click here)
The graph to the right shows the season's beginning. It is not good news.
Streams and rivers that form on top of the Greenland ice sheet during
spring and summer are the main agent transporting melt runoff from the
ice sheet to the ocean. Credits: NASA’s Goddard Space Flight
Center/Maria-José Viñas September 22, 2015
By Pakalolo
The Greenland ice sheet (click here) is the largest body of permanent ice in the Northern Hemisphere. Climate Change is happening swiftly in the Arctic, and consequently it is causing rapid and relentless melting of the sheet from both above (Albedo or dark ice) and below the ice due to warming ocean temperatures as well as large volumes of warm melt water at the bedrock). Most of us know that this run away melting is raising sea levels across the Globe. The hydrologic system of the Greenland ice sheet is extremely complex and there has been little data about how it works for some time. Slowly we are beginning to solve some mysteries.
Each summer, the hydrological system becomes activated as massive amounts of melt water produced on its surface, evaporates into the atmosphere, percolates into partially formed layers of ice, and feeds runoff into supraglacial lakes (a lake formed on top of the ice sheet), streams and rivers to the ice sheet margins.
Recently 2 sub-glacial lakes were discovered in Greenland. These lakes form below the ice and can stay unfrozen for decades. Particularly unusual is the fact that these lakes are associated with Antarctica and not the Arctic. They were unknown in Greenland until recently. The sub-glacial lake can be stable for decades, but can drain in one season and refill quickly with melt water from the surface....
