Abstract
Abstract. We have evaluated the magnitude and makeup of error in cryospheric radiation observations due to small sensor misalignment in in situ measurements of solar irradiance. This error is examined through simulation of diffuse and direct irradiance arriving at a detector with a cosine-response fore optic. Emphasis is placed on assessing total error over the solar shortwave spectrum from 250 to 4500 nm, as well as supporting investigation over other relevant shortwave spectral ranges. The total measurement error introduced by sensor tilt is dominated by the direct component. For a typical high-latitude albedo measurement with a solar zenith angle of 60°, a sensor tilted by 1, 3, and 5° can, respectively introduce up to 2.7, 8.1, and 13.5 % error into the measured irradiance and similar errors in the derived albedo. Depending on the daily range of solar azimuth and zenith angles, significant measurement error can persist also in integrated daily irradiance and albedo. Simulations including a cloud layer demonstrate decreasing tilt error with increasing cloud optical depth.
Subject
Earth-Surface Processes,Water Science and Technology
Reference39 articles.
1. Anderson, G., Clough, S.,
Kneizys, F., Chetwynd, J., and Shettle, E.: AFGL atmospheric
constituent profiles (0–120 km), Hansom AFB,
Bedford, MA, 1986.
2. Aoki, T., Aoki, T., Fukabori, M.,
Hachikubo, A., Tachibana, Y., and Nishio, F.: Effects of snow
physical parameters on spectral albedo and bidirectional reflectance
of snow surface, J. Geophys. Res., 105, 10219–10236, 2000.
3. Augustine, J. A.,
DeLuisi, J. J., and Long, C. N.: Surfrad – a national surface
radiation budget network for atmospheric resarch,
B. Am. Meteorol. Soc., 81, 2341–2357, 2000.
4. Bais, A. F., Kazadzis, S.,
Balis, D., Zerefos, C. S., and Blumthaler, M.: Correcting global
solar ultraviolet spectra recorded by a brewer spectroradiometer for
its angular response error, Appl. Optics, 37, 6339–6444, 1998.
5. Bernhard, G. and
Seckmeyer, G.: Uncertainty of measurements of spectral solar UV
irradiance, J. Geophys. Res., 104, 14321–14345, 1999.
Cited by
19 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献