Unmanned aerial vehicles (UAVs), also known as drones, are aircrafts that are able to be operated without a pilot on board. UAVs can either be controlled by a human being on the ground, or autonomously, through the use of a computer program1.
UAVs have already found several applications for military purposes, such as reconnaissance and attack roles, search and rescue operations as a result of their ability to provide a rapid overview of the situation, disaster relief purposes, due to their sustainable nature in extreme conditions, sports photography, wildlife and atmospheric research2,3.
Apart from being a great source of volatile and trace elements, volcanos play a key role in the geochemical cycling of trace elements through the Earth’s system. Despite this, large volcanic eruptions can negatively impact the global climate in several ways due to the lava, eruptive clouds formed from the ash, and the emitted gases, such as sulfur dioxide (SO2), hydrogen chloride (HCl), hydrogen sulfide (H2S) and hydrogen fluoride (HF)5.
Large quantities of carbon dioxide (CO2) that are produced during the volcanic eruptions can trap the heat radiated off the earth’s surface, thereby forming an insulation around the planet that results in an excessive warming on the global scale5.
Volcanic eruptions can also lead to the formation of atmospheric haze as a result of the injection of ash particles and sulfur rich gases into the troposphere and stratosphere, which decrease the amount of sunlight reaching the Earth’s surface5.
Sulfurous gases combine with water vapor that is present within the atmosphere to form acidic aerosols that absorb incoming solar radiation and scatter it back out into the space5. These sulfur aerosols take several years to settle out of the atmosphere, causing widespread and long lasting effects on global temperatures, as well as depletion of the ozone layer5.
Studying volcanos and the clouds will require the collection of data from hazardous and inaccessible volcanic environments, making it almost impossible to carry out such direct investigations6. Drones appear to be a promising solution to the challenges of the in situ sampling and routine monitoring of volcanic emissions, especially from the near vent regions where volcanos erupt.
Sensor-equipped drones provide valuable information to better the understanding of volcanos, while also helping in alerting local communities of impending eruptions6.
A team of volcanologists and engineers from the University of Bristol and Cambridge University have employed drones that are equipped with lightweight modern sensors to collect information regarding the temperature, humidity and thermal data that is present within the volcanic clouds of both Volcán de Fuego and Volcán de Pacaya in Guatemala6.
The sensor-equipped UAVs were able to reach distances of up to 8 kilometers (km) away and 10,000 feet above the launch site, successfully flying beyond visual line of sight (BVLOS) 6. Using these drones, Emma Liu’s team was able to take pictures of multiple volcanic eruptions, and the sensors of the drones allowed for the simultaneous measurement of the temperature, humidity and thermal data within the volcanic clouds6.
The multiple imaging flights from the observatory carried out by Liu’s team over several days allowed for the capturing of the rapidly changing topography of Fuego’s summit6. The topological mapping of the Fuego summit revealed that the volcano was erupting from two separate active vents. Furthermore, the team were also able to map the barranca, which is a term used to describe a narrow river gorge, and the volcanic deposits that are present within it6.
The researchers discovered that these deposits were recently formed by a pyroclastic flow, which is a fast-moving cloud of superheated ash and gas, that travelled down the barranca from Fuego6.
The data obtained using this drone technology will facilitate the modelling of the flow pathways, while also providing valuable information on the potential impact of future volcanic eruptions on nearby settlements6.
This group of researchers are currently working on how to incorporate additional sensors, such as atmospheric sensors and a multiGAS gas analyzer that would allow them to analyze CO2, SO2 and H2S, carbon stubs for ash sampling and thermal and visual cameras in order to improve the effectiveness of the drones in data acquisition6.
- “Drones” – Live Science
- “The UAV” – TheUAV.com
- "Search & Rescue: UAVs / Drones for Fire Service, Monitoring Etc." – Microdrones.
- “Volcano Facts and Types of Volcanos” – Live Science.
- “How do volcanos affect world climate?” – Scientific American
- “Drones collect measurements from a volcanic plume at Volcán de Fuego, Guatemala” – University of Bristol
- Image Credit: Shutterstock.com/loca4motion