Invention:
This invention is a location estimation method for the sky’s neutral points, specifically applied to the Babinet neutral point, that uses ultraviolet polarization imaging to determine the polarization signature of the sky. This invention further develops the Ultraviolet Linear Stokes Imaging Polarimeter (ULTRASIP), a ground-based instrument that captures ultraviolet light, to determine the position of the Babinet neutral point from linear Stokes images over 10 hours of observations. This invention has presented the first images of the Babinet neutral point in an ultraviolet waveband that can support future correlation studies between neutral point positions and atmospheric turbidity.
Background:
Monitoring the polarization signature of the sky can be a valuable tool for navigation, meteorology, and remote sensing, but the neutral points (Babinet, Brewster, Arago, and Fourth) are underutilized in these fields. Observations of the Arago and Babinet neutral points have shown that their positions are indicators of atmospheric turbidity, or aerosol content. The Aerosol Robotic Network (AERONET) is a method of taking ground-based measurements to determine atmospheric turbidity, but it has some limitations, such as the inability to process cloudy data. Unlike AERONET, neutral point positions do not rely on direct line-of-sight measurements. Taking neutral point observations can complement AERONET and offer a faster means of estimating atmospheric turbidity, which would be especially useful in scenarios that are quickly evolving, such as in the event of a wildfire.
Applications:
- Meteorology and climate research
- Navigation
- Remote sensing for atmospheric studies
- Air quality assessment
Advantages:
- Continuous and autonomous operation
- Reduced disturbances from clouds
- Rapid detection before turbidity is visible
