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Showing posts with label LiDAR. Show all posts
Showing posts with label LiDAR. Show all posts

Sunday, August 20, 2017

LIDAR, Connecticut Forests, and Iowa Marching Bear Effigy Mounds

       Dr. Katharine Johnson from the University of Connecticut (UConn) focuses on uncovering  
hidden remnants of the past using LIDAR imaging. The name LIDAR, sometimes considered an acronym of Light Detection And Ranging (sometimes Light Imaging, Detection, And Ranging), was originally a portmanteau of light and radar. Johnson and her colleagues have been piercing dense forest cover to uncover historic sites in New England (as seen here in Plainfield, Connecticut).

      

     Many of the tree-covered landscapes of modern New England were not always so green. In the 17th century, the region was the site of widespread deforestation, as European colonists built farms and homesteads. Between 60 to 80 percent of the land was cleared for fields, pastures, and orchards; these were surrounded with stone walls, houses, outbuildings, and roads.



      The natural-color photograph above was shot during an aerial survey in 2012. The monochromatic light detection and ranging (LIDAR) image, captured in 2010, shows the same area with greater contrast and reveals features on the ground. 




      LIDAR instruments send out rapid pulses of laser light that reflect off of solid surfaces (such as tree limbs or the ground). A receiver detects the photons that bounce back to the instrument, parsing out subtle variations in land elevation and allowing researchers to distinguish bumps and surfaces on the terrain.




      LIDAR has been used by archaeologists in other landscapes, perhaps most famously in Belize, where researchers have used it to uncover ancient Maya sites. The startling Marching Bear Effigy Mounds in northeastern Iowa were highlighted with LIDAR as well.

        


     “You can see patterns people made as they were dividing the landscape and farming,” said Johnson. LIDAR imaging helped them uncover traces of stone walls, dams, abandoned roads, building foundations, farm structures, and relict charcoal hearths—all of which have been slowly hidden over the past two centuries as the forest reclaimed the land.




 “The biggest surprise was being able to see the extent to which historic land use had impacted the landscape, which is not something that is readily visible in high-resolution aerial photos.”



Happy 24th birthday to Zoƫ today! Here she is celebrating with fellow Peace Corps volunteers in Ethiopia.



Have you used LIDAR?
Steph

Eclipse photos. Moonshadow. Moonshadow. . .How was your solar eclipse experience?








Eclipse at the Great Sand Dunes, Colorado--whoa!



Thursday, October 15, 2015

From "The Sound of Silence" to "Slip Sliding Away": The Great Sand Dunes and the Music of Paul Simon

     As the quietest of all of our 58 national parks, Great Sand Dunes National Park's theme song could readily be Paul Simon's "The Sound of Silence."


     The soft sounds of the blowing sand are often the only noises heard from the spectacular, relatively new adobe and wooden beams Visitor Center




               
                   or out on the dunes




            or watching "sand snakes"




or just taking it all in. Thirty square miles of dunes up to 750 feet tall is a lot to ponder. . .



and can be exhausting.


 Maizie is loving soaking up the sunshine as she takes this "Advice from a Sand Dune" very seriously.



          LiDAR (Light detection and Ranging) mapping of the San Luis Valley in 2011 (which includes the Great Sand Dunes) shows that the volume of sand is 1.5 cubic miles or 6.5 billion cubic meters (minus at least a cupful in my clothes, shoes, and camping gear). The San Luis Valley is the size of Connecticut, USA.



     LiDAR has also accurately mapped Star Dune at 750 feet, five dunes over 700 feet, and 37 dunes over 600 feet tall. LiDAR was responsible for mapping the Crestone Crater, a bowl-shaped depression about 100 meters (300 feet) across. The "crater" is of unknown origin but could be akin to the 5 makhteshim in Israel (thanks, SuperZee!) which are erosional cirques and not true craters of volcanic or meterorite origin.

      The earworms of "I am a Rock" and "Loves me Like a Rock" played often at the dunes




as did "Kodachrome"




and "Patterns"







     We drove less than a mile past the "Point of No Return" point on the Medano Back Country Road (Medano is Spanish for sand dune and is pronounced MED-a-no). Paul Simon's "Slip Sliding Away" was particularly apt and played long after that afternoon's adventure. Even with tire pressure lowered to 20 psi, it is quite a ride. . .




      This deer did not appear to have experienced "A Bridge over Troubled Water."


          We certainly did not have any troubled water as we were "Homeward Bound" after swimming in and camping near local hot springs:



*********Ahhhhhhhh.*********

Do you have a favorite Paul Simon song connected to a National Park memory?





Yes, we are duned!
Steph