This page describes the main features of the SHICrivm package.
The software package SHICrivm contains
- analysis of spectral wavelength shifts
- spectral anomalies (shape-errors, spikes, variability)
- calculation of standardized UV-spectra (common slit-function, common wavelength-scale)
- calculation of weighted UV-doses
The SHICrivm software package was developed over the past years in teh context of the EDUCE and SUVDAMA projects, aiming at improving the comparability of data sets obtained with different spectral instruments, and as a QA/QC-tool for checking or calibrating spectral wavelength shifts and spectral shape errors (spikes, variability). The methods have been extensively tested for a wide variety of instruments in the context of several large scale intercomparison campaigns, and in routine monitoring.
The SHICrivm software package combines several routines and includes the following functionality:
- a determination of wavelength dependent spectral wavelength scale errors/shifts of the measured solar UV-spectrum by comparing the spectral strucutre with a hiogh resolution extraterrestrial spectrum (shift determinations on 16 nm intervals from 290 nm up to 600 nm are possible; analysis up to 400 nm extensively tested)
- alignment of the measured solar spectrum, correction of the wavelength error/shift
- deconvolution of the measured spectrum (using the user-specified slit function or a triangular slit with user specified Full Width at Half Maximum FWHM)
- calculation of a spectrum corrected for wavelength shifts, and calculation of a standardised 1 nm FWHM spectrum (the latter two are based on the deconvolved spectrum)
- calculation of effective UV for a set of action spectra, and irradiances integrated over a set of wavelength intervals (using the deconvolved spectrum)
- check of the spectral structure, identifying possible (local) spectral anomalies (spikes in a spectrum)
- identification of the lowest irradiance levels where the readings become reliable, including the determination of the "starting" wavelength where readings become reliable
- full EDUCE-quality flagging: for wavelength shifts (spectral and integrated in two wavelength regions); flagging for spikes and spectral shape errors; flagging for lowest irradiance and starting wavelength of the spectrum; flagging for (cloud) variability during the scan
- identifaction of cloud-transmission and cloud varibility during the scan
- calculation of spectral atmospheric transmission (accounting
for earth-sun distance)
Developer and
contact: Harry Slaper
Laboratory for Radiation Research (LSO)
National Institute of Public Health and the
Environment
PO box 1
3720 BA Bilthoven
The Netherlands
harry.slaper@rivm.nl
Tel: 31 (0)30
2743488