Tethered Balloon System Operations & Modeling Efforts at ARM AMF3 Site at Oliktok Point, AK

Oliktok Point has been the home of the Atmospheric Radiation Measurement Program’s (ARM) third ARM Mobile Facility, or AMF3, since October 2013.  The AMF3 is operated through Sandia National Laboratories (SNL) and hosts instrumentation collecting continuous measurements of clouds, aerosols, precipitation, energy, and other meteorological variables.

SNL has operated ARM’s tethered balloon system (TBS) at the AMF3 since September 2015.  The TBS has operated within clouds and at altitudes up to 3,500’ AGL.  A variety of new instruments have been deployed on the TBS, including a Distributed Temperature Sensing (DTS) system.  The DTS uses optical fiber to measure temperature at 1 m spatial resolution along the tether.  Supercooled liquid water content (SLWC) sensors have been deployed simultaneously with the DTS.  A Printed Optical Particle Spectrometer (POPS) and miniSASP (Scanning Aerosol Solar Photometer) have also been deployed on the TBS.  Wind speed, pressure, temperature, and humidity are recorded at multiple locations along the tether during all flights.  The TBS has profiled throughout the cloud layer over several hours, and data from the TBS have been compared with ground-based instrumentation at the AMF3.

Atmospheric general circulation models (AGCM) are used to improve understanding of atmospheric processes, but often contain biases leading to unrealistic atmospheric states in the Arctic.   It is expected that improvements in AGCMs, combined with in situ cloud and meteorological measurements, will improve understanding of physical processes and help AGCMs better characterize the Arctic.  AALCO (Aerial Assessment of Liquid in Clouds at Oliktok), is an ARM field research campaign being conducted by SNL at the AMF3.  Under AALCO, SLWC sensors have been deployed on the TBS in order to reduce the number of unknown inputs in high-resolution Arctic cloud modeling.  The prognostic ice concentration in the System for Atmospheric Modeling, a Large-Eddy Simulation (LES), was tuned to be in agreement with the in situ measurements reported by the SLWC sensors.

This presentation will provide an overview of the sensors used, analysis of the data collected by the TBS, and an overview of modeling efforts complemented by the TBS data.