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Global Airborne Observatory

The Global Airborne Observatory (GAO), formerly the Carnegie Airborne Observatory (CAO), is an airborne laboratory developed by Dr. Greg Asner and his team that houses advanced Earth mapping technology. The GAO's mission is to make scientific discoveries, support conservation, and galvanize action to protect the environment at large geographic scales. Now in its third generation, the GAO is a complete airborne laboratory based on a highly modified Dornier 228-202 aircraft, and it carries what is widely regarded as the most advanced mapping technology operating in the civil sector today. 

The original CAO was launched in 2006 and has since undergone significant improvements in both the aircraft itself and in its instruments and computing package, which is called AToMS or Airborne Taxonomic Mapping System. AToMS is now in its fourth generation configuration, with advances in all sensors. AToMS has four integrated remote sensing technologies: (i) High Fidelity Visible-Shortwave Infrared (VSWIR) Imaging Spectrometer; (ii) Dual-laser, waveform Light Detection and Ranging (wLiDAR) Scanner, (iii) High-resolution Visible-to-Near Infrared (VNIR) Imaging Spectrometer, and (iv) High-resolution Digital Imaging Camera. The VNIR sensor images the chemical content of forests in fine spatial resolution. The VSWIR sensor measures the reflectance of the Earth's surface in 427 channels from the ultraviolet through the visible near-infrared and short wave infrared, allowing it to measure the chemicals in the environment, such as tree canopies, in fine spectral resolution. The wLiDAR sensor fires two laser beams out of the bottom of the GAO that sweep back and forth during flight, imaging the geometry of the forest by measuring all of the structure below, treetops, branches, and all the way to the ground.

Together, this system collects data about the structural, taxonomic, and chemical makeup of ecosystems and is able to map features on the Earth's surface in three dimensions, including all terrestrial ecosystems and human-built environments. AToMS can also image coral reefs and other aquatic habitats with spectral detail. Since the GAO is airborne, it can achieve a bird's eye view of ecosystems, gathering vast amounts of data at a scale humans can't measure and over many regions that humans can't reach, such as deep in the Amazon rainforest. 

The GAO has been deployed over a global range of ecosystems—from coral reefs to savannas to rainforests—in numerous countries such as Belize, Borneo, Colombia, Costa Rica, the Dominican Republic, Ecuador, Madagascar, Mexico, Peru, South Africa, parts of the U.S. (California and Hawaii), and St. Croix in the U.S. Virgin Islands. The data collected has contributed to significant discoveries, such as locating previously undetected illegal gold mining in the Amazon and the world’s tallest tropical tree (294 feet) in the Bornean rainforest. The maps derived from GAO data have directly shaped policy and conservation, such as efforts to track and contain a tree-killing fungus in Hawaii and plans for creating a new marine protected area in the Dominican Republic. The GAO has transformed our understanding of natural and managed ecosystems over large geographic scales to improve conservation, sustainable resource use, and environmental policy.

GAO Sensors
The VNIR sensor (red box) measures the chemical content of forests in fine spatial resolution while the VSWIR sensor (shiny gold) measure s the chemical content of forests in fine spectral resolution; they both measure reflected light but in different wavelengths. The wLiDAR sensor (white box) maps the geometry of the forest by measuring all of the structure below, treetops, branches, and all the way to the ground.