The three-dimensional view of the dense Amazon forest have given the NASA researchers a scope for in-depth analysis of the significant number of branch falls as well as tree mortality that occurs at the time of drought conditions. Such research has lead to the revealing of the fact that El Nino-driven drought that happened in the year of 2015-16 led to the death of almost 65 percent of trees and branches as compared to an average death in any particular year. As the scientists can have a detailed analysis of such effects of drought, it will give them a better picture to understand what could be the condition of carbon that is present within the tropical forest if such natural calamities take place more frequently in the coming future.
According to Mr. Doug Morton, who is an Earth system scientist at the Goddard Space Flight Centre of NASA which is situated at Greenbelt, Maryland said that the climatic assumptions for the Amazon basin exhibit warmer and drier conditions in the coming days. He further added that droughts give the scientists a brief idea about how tropical forests will react to warmer conditions.
In the absence of abundant rainfall in the tropical forest regions, it becomes difficult for the trees to suck in more water from the soil and sent them to their canopies which are almost 15 to 20 stories high. As a result, the risk of trees dying becomes more. It is a huge challenge to identify the number of trees that are dying in a rainforest as vast as Amazon, mainly when branches falling are more in numbers.
Usually, researchers make an overall survey of a few acres of land to find out the living trees and also the dead debris on the ground. With the help of Light Detection and Ranging (LiDAR), Morton and his teammates took resort to bird’s eye approach. They mounted this technology on the top of an airplane to create a 3D reconstruction of the look-alike forest spanning over three different flights in the year of 2013, 2014 and 2016.
In Brazil, a team of researchers flew for over two 30 mile swaths close to the city of Santarem within the state of Para. One of the expeditions was carried over Tapajos National Forest while the other team was carried over privately owned forest which had got fragmented as a result of land issues.