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Abstract The THINICE field campaign, based from Svalbard in August 2022, provided unique observations of summertime Arctic cyclones, their coupling with cloud cover, and interactions with tropopause polar vortices and sea ice conditions. THINICE was motivated by the need to advance our understanding of these processes and to improve coupled models used to forecast weather and sea ice, as well as long-term projections of climate change in the Arctic. Two research aircraft were deployed with complementary instrumentation. The Safire ATR42 aircraft, equipped with the RALI (RAdar-LIdar) remote sensing instrumentation and in-situ cloud microphysics probes, flew in the mid-troposphere to observe the wind and multi-phase cloud structure of Arctic cyclones. The British Antarctic Survey MASIN aircraft flew at low levels measuring sea-ice properties, including surface brightness temperature, albedo and roughness, and the turbulent fluxes that mediate exchange of heat and momentum between the atmosphere and the surface. Long duration instrumented balloons, operated by WindBorne Systems, sampled meteorological conditions within both cyclones and tropospheric polar vortices across the Arctic. Several novel findings are highlighted. Intense, shallow low-level jets along warm fronts were observed within three Arctic cyclones using the Doppler radar and turbulence probes. A detailed depiction of the interweaving layers of ice crystals and supercooled liquid water in mixed-phase clouds is revealed through the synergistic combination of the Doppler radar, the lidar and in-situ microphysical probes. Measurements of near-surface turbulent fluxes combined with remote sensing measurements of sea ice properties are being used to characterize atmosphere-sea ice interactions in the marginal ice zone.
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Guided Observations of Dynamic Shear Instability Layers over Antarctica (GODSILA) field campaign dataset
The GODSILA (Guided Observations of Dynamic Shear Instability Layers over Antarctica) field campaign was carried out over 44 days between the 25th of December 2023 and the 6th of February 2024 at the Antarctic Syowa Station to achieve the primary research goals of this project. In situ measurements of standard meteorological parameters including high-resolution turbulent wind and temperature fluctuations were acquired using a custom balloon-borne instrument called HYFLITS (Hypersonic FLights in the Turbulent Stratosphere) concurrently with twice daily radiosonde launches. Continuous observations from the PANSY radar system surveyed the tropo-stratospheric column over Syowa Station throughout the field campaign. The PANSY radar data and the twice-daily AMPS forecasts were extensively used to determine the HYFLITS instrument deployment schedules. The GODSILA field campaign dataset comprises in situ meteorological measurements from 40 successfully deployed HYFLITS payloads, 96 radiosonde soundings, and over 1000 hours of PANSY radar observations of mean and turbulent wind components.
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- Award ID(s):
- 2326960
- PAR ID:
- 10644919
- Editor(s):
- Doddi, Abhiram; Lawrence, Dale
- Publisher / Repository:
- U.S. Antarctic Program (USAP) Data Center
- Date Published:
- Edition / Version:
- 1
- Subject(s) / Keyword(s):
- Air Temperature Pressure Relative Humidity Turbulence Wind Speed Polar Atmosphere
- Format(s):
- Medium: X Size: 400MB Other: .nc
- Size(s):
- 400MB
- Institution:
- University of Colorado Boulder
- Sponsoring Org:
- National Science Foundation
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