The effect of temporal variations in atmospheric optical depth on the determination of the zero-airmass voltage via Langley plot fitting of solar radiometer data is analyzed. It is shown that short-term variations in optical depth can be detected fairly accurately with only an approximate estimate of the zero-airmass voltage. Simulations are presented to assess the effect of specific time variations in optical depth on zero-airmass voltage determinations. It is shown that the fractional error in the zero-airmass voltage determination varies in an approximately one to one relation to the absolute change in optical depth. It is also shown that the error in the zero-airmass voltage determination can be much greater than the standard deviation of this voltage obtained form the least-squares straight-line fit of the Langley plot data.
|Original language||English (US)|
|Number of pages||5|
|Journal||European Space Agency, (Special Publication) ESA SP|
|State||Published - Dec 1 1984|
ASJC Scopus subject areas
- Aerospace Engineering
- Space and Planetary Science