Probing the vertical structure of the lower atmosphere over Svalbard

This is chapter 9 of the State of Environmental Science in Svalbard (SESS) report 2019 (https://sios-svalbard.org/SESS_Issue2). Understanding the causes and mechanisms of climate change requires an enormous number of continuous and accurate measurements. To measure atmospheric parameters along the vertical profile, one must either fly the instrumentation or infer such information at a distance from the emissions or reflections of components in the atmosphere (remote sensing). Techniques that use one of these approaches have been developed since the 1940s. However, both approaches suffer from limitations on the accuracy of the measurements and the amount of information that can be obtained. Recent technological development has enabled production of small, low-cost sensors with capabilities similar to those used in the laboratory. These sensors can be installed on balloons or small unmanned aerial vehicles, allowing direct measurements in the lower atmosphere. With more accurate information on the status of the atmosphere, researchers can refine their mathematical data interpretation techniques. The research station in Ny-Ålesund is already well equipped for a number of standard vertical profile measurements. Fewer activities are performed at other stations in Svalbard. This is clear from the studies we cited in our contribution: about 60 papers. Half were based on remote sensing, 22 on balloons (tethered or free), 5 on dropsondes and 5 on drones. Although we do not claim that this list is exhaustive, it may represent the status of activities in Svalbard. The limited air traffic in the Arctic means that carrying out measurements with balloons and small radio-controlled airplanes is easier than elsewhere.