Spectral UV

Instrument Working Group

Long Term Changes in UV
Attribution of Changes in UV
UV Sky Radiance Measurement
UV Effects from Australian Bushfires
Uncertainty Evaluation in Measurement and Modeling of UV Irradiance
Health Effects of UV Radiation
Long-Term UV Measurements in Polar Regions

The main aim of the NDACC Spectral UV group is to maintain the highest quality measurements of spectral UV irradiance, and to make them accessible to researchers in order to better understand geographical and temporal differences.

Figure 1 illustrates why spectral measurements, rather than broad band measurements of quantities such as erythemally-weighted irradiances (peaking near 305-310 nm), are required for trend detection.

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Graph of sensitivity to ozone change as a function of wavelength

Figure 1. Sensitivity to ozone change as a function of wavelength

 

Our particular interest is in detecting long term changes in UV, and attributing the causes of those changes. Times series of weighted irradiances are archived in the NDACC database. Full spectral data are available from the instrument PIs.

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Graph depicting comparison of spectra from UV spectrometers at 3 NDACC sites and one urban site.

Figure 2. Comparing spectra from UV spectrometers at 3 NDACC sites and one urban site.

Data Requirements: The data requirements for acceptance by NDACC are demanding. Detailed data specifications, and instructions to apply for NDACC acceptance are provided on this website under the 'DATA' tab, then select 'Protocols'.

The results of inter comparison campaigns are used to understand capabilities and limitations of spectrometer systems before acceptance to NDACC.  See for example:

Bernhard, G., R. L. McKenzie, M. Kotkamp, S. Wood, C. R. Booth, J. C. Ehramjian, P. Johnston, and S. E. Nichol (2008),Comparison of ultraviolet spectroradiometers in Antarctica, J. Geophys. Res., 113, D14310, doi:10.1029/2007JD009489.

Pissulla, D. , Seckmeyer G., Cordero R. R., Blumthaler M., Schallhart B., Webb A., Kift R., Smedley A., Bais A. F., Kouremeti N., Cede A., Herman J., Kowalewski M.: Comparison of different calibration methods to derive spectral radiance as a function of incident and azimuth angle, Photochem. Photobiol. Sci., 2009, 8, 516 - 527, DOI: 10.1039/b817018e, 2009.

Group Meetings

Most group interaction is via e-mail, apart from meetings associated with other events.