Thousands of days ago , the Sahara desert was a lush and verdant topographic point more consanguineal to a savannah , wheregiraffes , hippopotamus , and crocodilesroamed , farmers countenance their dairy herds graze , andpeople wipe out a lot of fish . A vast lake – bigger than the Caspian Sea , the humanity ’s biggest lake today – resided in Central Africa , sprawl 400,000 square kilometre ( 150,000 square miles ) , realize it the soubriquet Lake Mega Chad .
Sometime around 7,000 eld ago , the wet , humid estate became one of the most inhospitable space on Earth ; the vast sandlike desert we recognize today . Lake Chad still exist , but it ’s a darkness of its former self . Like therock prowess and bonesthat differentiate us the animate being that once roamed this savannah , grounds of this once - with child consistence of H2O can still be seen in the ancient shorelines etch into the landscape painting .
In one of the most striking recent images from itsImage of the Dayseries , NASA ’s Earth Observatory has revealed this incredible persuasion of it from above .
Data from the Shuttle Radar Topography Mission ( SRTM ) reveal the former shoreline ; lower - elevation areas appear darker in the look-alike , while a exposure engage by NASA and the United States Geological Survey ’s ( USGS ) Landsat 8 satellite locates the present - day lake .
The tiptop data also highlight the ridges and Baroness Dudevant spit that formed along its northeast shore . In the Holocene , when Mega Chad flourish , winds blew from the northeastern United States , drive currents that push the grit and sediment to build toward the southwest .
Lake Chad still sits inside the tail of its ancient large babe but it only took a twosome of hundred years to shrink to its current 350 square kilometers ( 135 square miles ) . Bordered on all side by Chad , Cameroon , Niger , and Nigeria , around 40 million hoi polloi rely on the lake for freshwater and resource , stand for that overuse , as well as droughts give to desertification , are do it to shrivel further .
NASA ’s Earth Observatory is a vital tool for studying our satellite and even getting a glimpse into our past . We often reckon of NASA as indicate towards the star , but when we remember topoint the lens back at Earth , not only do we learninvaluable data about our world , it ’s nice to be reminded that we are also , in fact , rather beautifulto await at too .
