New USDA UVB synthetic spectra algorithm

John M. Davis; James R. Slusser

doi:10.1117/12.620269

12 September 2005 New USDA UVB synthetic spectra algorithm

John M. Davis, James R. Slusser

Proceedings Volume 5886, Ultraviolet Ground- and Space-based Measurements, Models, and Effects V; 58860B (2005) https://doi.org/10.1117/12.620269
Event: Optics and Photonics 2005, 2005, San Diego, California, United States

Abstract

The US Department of Agriculture's (USDA), UVB Radiation Monitoring and Research Program¹ makes routine measurements of ultraviolet radiation at over 30 sites in the United States, Canada and New Zealand. UV measurements of total, direct and diffuse horizontal irradiances, in seven spectral channels at two nm nominal bandwidths are made with a Yankee Scientific Inc., Multiple Filter Rotating Shadow band Radiometer (UV MFRSR). A similar instrument takes measurements in the visible region with 10 nm bandwidths. The UVB group has provided, upon request, a high resolution UV product referred to as "synthetic spectra," based on application of a non-linear estimation method described in Min and Harrison² (1998) to UV MFRSR data. This presentation examines typical problems encountered when the synthetic spectra algorithm is applied to data collected at large solar zenith angles and when the application is extended to spectral regions beyond 368 nm, the center of the longest wavelength UV MFRSR channel. In particular, the effects on derived products such as the Caldwell or Flint³ action spectra are discussed. The useful spectral region of the algorithm has been expanded by including one or more of the datum from the visible MFRSR. This extension properly constrains the derived spectrum beyond 368 nm providing especially improved Flint action values, and can be used to estimate a PAR value if extended to include the 862 nm measurement. The extent of disagreement between measurements from LICOR PAR sensors and 'synthetic PAR' values will be presented. Planning for the next version of the synthetic spectra algorithm on the new USDA UVB web site is discussed.

Citation Download Citation

John M. Davis and James R. Slusser "New USDA UVB synthetic spectra algorithm", Proc. SPIE 5886, Ultraviolet Ground- and Space-based Measurements, Models, and Effects V, 58860B (12 September 2005); https://doi.org/10.1117/12.620269

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available