Obstacles

This page is part of the UV Exposure Model (UVEM) documentation.
It contains a documentation about the implementation of obstacles in the basic uv exposure model.
For an overview of all UVEM-related pages, see the UV Exposure Model main page?.

3-dimensional UV Exposure Model in an Urban Environment

To calculate the biologically weighted human exposure in an obstructed environment, where for example buildings or vegetation are covering parts of the sky, information about the present obstructions for each considered location are needed. The additional parameter obstruction (obs) is included in the exposure model equation presented in section basic model? and is then given by:

The additional parameter obstruction depends on the azimuth and incident angle and contains the information to what percentage the sky is visible (unobstructed) for the corresponding solid angle (direction). Due to the low reflectivity of most surfaces in the UV wavelength range, it is assumed that the radiance from obstructed sky regions can be neglected.

Determination of obstrcution information

The obstruction information can be derived from topography data (voxel data). In the Figure on the left an examplary imaginary three-way intersection is shown. The different colors indicate different building height and the red miniature block in the middle represents a human.

The obstruction information can be derived from topography data (voxel data). In the Figure on the left an examplary imaginary three-way intersection is shown. The different colors indicate different building height and the red miniature block in the middle represents a human. NOCH DOPPELT

References:

• Seckmeyer, G., Schrempf, M.Wieczorek, A., Riechelmann, S., Graw, K., Seckmeyer, S., and Zankl, M. 2013. A Novel Method to Calculate Solar UV Exposure Relevant to Vitamin D Production in Humans, Photochem. Photobiol., 89(4), 974-983, DOI: 10.1111/php.12074.
• Schrempf, M., Thuns, N., Lange, K., and Seckmeyer, G. 2017a. Einuss der Verschattung auf die Vitamin-D-gewichtete UV-Exposition eines Menschen, Aktuelle Derm, DOI: 10.1055/s-0043-105258.
• Schrempf, M., Thuns, N., Lange, K., and Seckmeyer, G. 2017b. Impact of Orientation on the Vitamin D Weighted Exposure of a Human in an Urban Environment, Int. J. Environ. Res. Public Health, 14(8), 920, DOI: 10.3390/ijerph14080920.