A Bird’s-Eye View: Development of an Operational ARM Unmanned Aerial Capability for Atmospheric Research in Arctic Alaska

Abstract

Thorough understanding of aerosols, clouds, boundary layer structure, and radiation is required to improve the representation of the Arctic atmosphere in weather forecasting and climate models. To develop such understanding, new perspectives are needed to provide details on the vertical structure and spatial variability of key atmospheric properties, along with information over difficult-to-reach surfaces such as newly forming sea ice. Over the last three years, the U.S. Department of Energy (DOE) has supported various flight campaigns using unmanned aircraft systems [UASs, also known as unmanned aerial vehicles (UAVs) and drones] and tethered balloon systems (TBSs) at Oliktok Point, Alaska. These activities have featured in situ measurements of the thermodynamic state, turbulence, radiation, aerosol properties, cloud microphysics, and turbulent fluxes to provide a detailed characterization of the lower atmosphere. Alongside a suite of active and passive ground-based sensors and radiosondes deployed by the DOE Atmospheric Radiation Measurement (ARM) program through the third ARM Mobile Facility (AMF-3), these flight activities demonstrate the ability of such platforms to provide critically needed information. In addition to providing new and unique datasets, lessons learned during initial campaigns have assisted in the development of an exciting new community resource.

The relative impact of cloud condensation nuclei and ice nucleating particle concentrations on phase partitioning in Arctic mixed-phase stratocumulus clouds

“…For example, in the Indirect and Semi-Direct Aerosol Campaign (ISDAC) that took place off the coast of Utqiaġvik, (Barrow) Alaska, in the spring of 2008, the number of INPs available were observed to be 4 orders of magnitude smaller than the number of aerosols serving as CCN. However, it is important to note that only a few INPs are needed to glaciate a cloud (see discussion in DeMott et al, 2010).…”

Atmospheric observations made at Oliktok Point, Alaska, as part of the Profiling at Oliktok Point to Enhance YOPP Experiments (POPEYE) campaign

“…Additionally, a Silixa XT distributed temperature sensing (DTS) system was flown. This system, which includes a long fiberoptic cable suspended along the tether, provides a high-resolution, continuous measurement of air temperature based on Raman scattering (Keller et al, 2011;de Jong et al, 2015). Using this system, the temperature is typically measured along the length of the optical fiber every 30 to 60 s at 0.65 cm spatial resolution.…”

HOVERCAT: a novel aerial system for evaluation of aerosol–cloud interactions

“…In addition, the launched balloon platforms provide information on one to two aerosol profiles (i.e., ascent and sometimes descent) and are limited by payload weight. Particle spectrometers have also been deployed and retrieved on tethered balloon systems (de Boer et al, 2018;Greenberg et al, 2009;Maletto et al, 2003;Renard et al, 2016;Siebert et al, 2004;Wehner et al, 2007), affording information on aerosol layer locations and evolution by means of multiple profiles. A few studies have deployed miniature aerosol filter samplers on launched or tethered balloon systems, yielding information on aerosol chemistry (Hara et al, 2011;Rankin and Wolff, 2002); however, such samplers contained one filter per flight, thus providing information on aerosol properties at only one altitude (i.e., not a profile).…”