Hi to All
Are there any Model that calculate the Albedo of a complex urban texture? I am familiar with Photon Tracking method based on Monte Carlo method for calculating the Urban Albedo, and I'v read articles that introduce this method. I'v seen also a web-based Calculator that calculate urban albedo of a simple model with only four buildings and three options of building patterns.
Regards
Alipour
Dear Mykhailo Illich Fyk
I want to calculate the "Albedo" of a real urban area, including all its elements, such as buildings, trees, roads and ... . As I said, I found only one model for calculating "Urban Albedo" with mentioned method that considers only four building blocks without trees. and results of this model as it does NOT consider trees are far from real values.
Alipour
I concur with Mykhailo - what is the problem you are seeking to solve? If you are trying to measure the amount of solar energy being reflected into the atmosphere above a city, why? What is the underlying problem that the answer to this question would help you solve?
Dear Shawn Zhang
ENVI-met model does not provide the Albedo of the simulated area as an output. The Albedo value in the simulation outputs of ENVI-met (in the Building folder), is the surface albedo that specified by the user. With few exceptions, the Albedo of an urban area can be obtained by the ratio of "Reflected Sw Radiation" to "Direct Sw Radiation+Diffuse Sw Radiation" at top of 3D model. in this way, the reflected Lw Radiation and Lw radiation from upper-hemisphere will not be considered.
Generally, the use of ENVI-met results to obtain Albedo values has two disadvantages. First, it is very time consuming, and second, it doesn't provide reflected long wave radiation.
Regards
Alipour
Difficult to find a simple answer to your question. Try to scan the outcomes from the last conference on Urban Climate in Web (http://www.meteo.fr/icuc9). There is a lot of short papers related to your problem, and I suggest to contact the authors, for example:
Neighbourhood morphology and solar irradiance in relation to urban climate, by Mohajeri et al.
On the impact of surface heterogeneities on the radiative response of a simplified urban surface, by Kotthaus et al.
Simulation of urban fluxes with a 3D canopy model, by Kastendeuch and Najjar.
Regards
Valeri Goldberg
Dear Goldberg
Thanks for your attention and helpful recommendation.
Best regards
Alipour