System for Analysis of Wind Collocations (SAWC)

Aeolus level-2B (L2B) winds were derived from backscattering signals retrieved by the Aladin Flight Module A (FM-A) (or the backup FM-B) Doppler wind lidar instrument onboard ESA’s Aeolus satellite that traveled on a dawn/dusk orbit. The satellite completed one orbit approximately every 92 min, with global coverage achieved every 7 days. Winds were observed in profile along the laser’s Horizontal Line-of-Sight (HLOS).

Two main wind regimes were derived using ESA’s L2B processor: (1) Rayleigh-clear (molecular backscattering) representing winds in clear scenes, and (2) Mie-cloudy (aerosol backscattering) representing winds in cloudy scenes. Temporal coverage of the archived data spans the entire lifetime of Aeolus .

Loon was a network of stratospheric superpressure balloons deployed by Loon, LLC, a subsidiary of Google’s parent company Alphabet, to provide internet connectivity to regions with limited access from 2011-2021. The balloon configurations consisted of an instrument payload platform tethered to a tennis court-sized balloon specifically designed to withstand harsh stratospheric conditions. The balloons remained aloft for months at a time, and a ground team was able to control their movements by remotely adjusting the balloon pressure in order to move the configurations into different airstreams.

The dataset includes GPS and in situ sensor data from over 2000 flights across the project’s history. The observations were reported at balloon level (50-110 hPa or 18-20 km) at a frequency of ~1-20 minutes. The spatial coverage depended on the Loon mission at the time of deployment. Temporal coverage of the archived data spans from 2011 to 2021 when the Loon project ended.

Sondes (radio-, drop-, or rawinsondes) report in situ observations in profile at balloon level from the lower troposphere to the stratosphere. The observations are stratified by type of report, including but not limited to: rawinsondes launched from land and ship, dropsondes, and pilot balloon data (PIBAL) reports. The spatial coverage is limited to sonde launch sites, the majority of which are located on land.

Aircraft observations are reported at flight level in the upper troposphere/lower stratosphere (cruise altitude) and in the ascending and descending legs of each flight. The observations are stratified by type of report, including but not limited to: aircraft meteorological data reports (AMDAR) from the US, Canada, Europe, Korea, and others; US meteorological data collection and reporting system (MDCRS); tropospheric airborne meteorological data reporting (TAMDAR); and aircraft and pilot reports on weather conditions encountered during flight. The spatial coverage is dependent upon international commercial flight paths.

Atmospheric motion vectors are derived from tracking clouds and water vapor features in satellite imagery through time. The archived AMVs are winds derived from observations from both geostationary (GEO) and polar Earth-orbiting (LEO) satellites, including but not limited to GOES, NOAA, S-NPP, Himawari-8, Aqua, Terra, METOP, and METEOSAT. The complete dataset provides near-global spatial coverage at various vertical levels.