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09:55
Surface Renewal: An Advanced Micrometeorological Method for Measuring and Processing Field-Scale Energy Flux Density Data
Published on: December 12, 2013
Initial ground-based thermospheric wind measurements using Doppler asymmetric spatial heterodyne spectroscopy (DASH)
Christoph R Englert1, John M Harlander, John T Emmert
1US Naval Research Laboratory, Space Science Division, Washington, District of Columbia 20375, USA. Christoph.Englert@nrl.navy.mil
Optics Express
|January 4, 2011
Summary
We report the first thermospheric wind measurements using a Doppler Asymmetric Spatial Heterodyne (DASH) spectrometer. This novel technique provides accurate wind data despite challenging conditions, validating against established methods.
Area of Science:
- Atmospheric Science
- Geophysics
- Optical Spectroscopy
Background:
- Accurate measurements of thermospheric winds are crucial for understanding upper atmosphere dynamics and space weather.
- Traditional methods for thermospheric wind measurement face limitations in certain environmental conditions.
- The oxygen red-line nightglow emission is a key indicator of thermospheric processes.
Purpose of the Study:
- To demonstrate the efficacy of a Doppler Asymmetric Spatial Heterodyne (DASH) spectrometer for thermospheric wind measurements.
- To present the first ground-based measurements of thermospheric winds using DASH and the oxygen red-line emission.
- To assess the quality and reliability of DASH wind data under challenging observational conditions.
Main Methods:
- Utilized a Doppler Asymmetric Spatial Heterodyne (DASH) spectrometer for ground-based observations from Washington, DC.
- Employed the oxygen red-line nightglow emission as the target spectral feature.
- Incorporated simultaneous calibration measurements to correct for instrument drifts and ensure data accuracy.
Main Results:
- Successfully obtained high-quality thermospheric wind measurements despite challenging thermal and light pollution conditions.
- Achieved photon statistics uncertainties ranging from approximately 3 to 29 m/s, contingent on nightglow intensity.
- Demonstrated that the DASH-derived wind data are comparable to established Fabry-Perot interferometer measurements from Millstone Hill under similar solar and geomagnetic conditions.
Conclusions:
- The Doppler Asymmetric Spatial Heterodyne (DASH) spectrometer is a viable and effective instrument for thermospheric wind measurements.
- This new method provides reliable wind data even in the presence of environmental noise and instrument drift.
- The results validate the DASH technique against existing methodologies, paving the way for broader application in upper atmospheric research.
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