A new video by the NASA shows what our planet would look like if the oceans dried up, reports Forbes.
In 2008 Dr. Horace Mitchell, from NASA, made an animated video where the three-fifths of the globe’s surface that are covered by the ocean could be seen. Now Dr. James O’Donoghue, a scientist in Japan’s Aerospace Exploration Agency, before with NASA, has remade the video with better resolution. The animation is slower at first to see the continental shelves as the sea level starts to drop.
The video provides interesting information about human evolution at a time when the sea levels were lower. The last glacial maximum (LGM) was the time during the Last Glacial Period when the extent of ice sheets covering North America, Northern Europe and Asia was at its peak. It occurred between 26,000 and 19,000 years ago. Because much of the ocean’s water was frozen on top of continents, the sea level was about 125 meters lower than today.
Shaded relief image of the Earth's topography and bathymetry. Credit: NASA
As we watch sea levels starting to drop in the video, we can see land bridges appear joining continents and islands, bridges which early humans used to migrate around the globe: from continental Europe to the British Isles, from eastern Siberia through the Bering Strait to Alaska. Land also connected parts of Southeast Asia and Australia.
Also interesting to observe in the video as the sea levels continue to drop is the appearance of oceanic ridges ─ mountain ranges where the seafloor spreads along a divergent plate boundary ─ for instance, in the centre of the Atlantic and Pacific Oceans.
Although we do not need to be concerned about sea levels lowering anytime soon, the video provides an interesting look at the world our ancestors lived in, and what it might look like again during the next ice age. It is also a reminder of how the Earth’s climate has changed at the geologic time scale and the profound effects on the human species.