Speaking of the famous Sahara Desert, I believe few people are unfamiliar with it. The Sahara Desert is the largest desert globally, covering an area of over 9 million square kilometers. It stretches approximately 4,800 kilometers in length and 1,800 kilometers in width, making it 27 times the size of China's Taklamakan Desert. Just the thought of it is chilling.
The Sahara Desert is located in northern Africa and boasts the harshest climate conditions globally. Characterized by prolonged droughts and high temperatures, it can even reach highs of 57.7°C at times. When viewed on satellite maps, the northern part of the Sahara Desert appears as a reddish-brown color, regarded by humans as the most inhospitable area for life on Earth. It is indeed the world's driest desert.is indeed the world's driest desert.
Many people are under the impression that in the endless Sahara Desert, there may be only inexhaustible golden sand and scorching sunlight, and building a solar power station is a good idea, because there seems to be nothing else. Can use barren barren, lifeless, barren, desolate, desolate, silent and other words to express its desolation and tragedy. But this is not the case, and today the western Sahara Desert has undergone a welcome change, an area of about 1.3 million square kilometers of desert covered with trees and mountains.
In 2020, researchers from the University of Copenhagen in Denmark and the National Aeronautics and Space Administration (NASA) in the United States collaborated to form an international team to conduct field surveys of the environment in West Africa. They were astonished to find that the Sahel region and semi-humid areas were home to a significant amount of tree growth. The trees were spaced only a few meters apart from each other, and if the density of trees were to double, it could form a vast forest.
Obviously, this new discovery has overturned many people's perceptions. Prior to this, it was widely believed that this area was barren. In response, NASA deployed high-tech reconnaissance satellites to survey the tree count across the entire West African region. They utilized a sophisticated algorithm provided by researchers from the Computer Science Department at the University of Copenhagen. This algorithm enabled computers to rapidly count trees over large areas and quickly determine the total quantity. The survey revealed the astonishing presence of 1.8 billion trees over 1.3 million square kilometers of land, averaging 13.4 trees per hectare.
Photos show that several regions in West Africa have undergone remarkable transformations, with vast numbers of trees sprouting up across the landscape, evenly distributed across sandy terrain.
It's worth mentioning that the algorithm provided by experts at the University of Copenhagen is actually a deep learning model capable of identifying other trees based on the shape of one tree. Consequently, it can automatically recognize thousands of satellite images from NASA satellites. In just a few hours, it can tally the number of trees in all satellite images, thus generating a comprehensive tree map.
If we were to rely on manual counting, it's likely that it would take a lifetime or more to complete the task. It goes to show the tremendous convenience that advancements in science and technology bring to many areas of scientific research.
