Horst trebs driver#
The relevance of the problem of pollutant dispersion has been a primary driver for many research efforts focused on atmospheric processes over complex terrain in recent decades. As a consequence, significant concentrations of harmful species, especially secondary pollutants, may also be found in areas where they were not locally emitted. Furthermore, pollutants may be transported by orographic flows towards mountainous areas from adjacent regions, where they are emitted. High levels of pollutants are harmful, not only to humans, wildlife and livestock, but may also cause damage to the environment, especially vegetation and forest heritage. In fact, in such conditions, atmospheric dispersion, i.e., the combined effect of transport/advection by the mean wind and diffusion due to turbulent mixing, may be strongly inhibited.
Under unfavorable meteorological situations, pollutants may accumulate at the bottom of valleys and basins, implying that a large part of the population is potentially exposed to high concentrations. This is shown, as an example, in Figure 1, displaying annual emissions of NO x and PM 10 in South Tyrol, in the Italian Alps. Major sources of pollutants in mountainous regions are generally located inside valleys and basins, where the main urban areas and traffic routes develop, and most of the population lives. In particular, one of the most serious hazards involves pollutant emissions and their effects on air quality. As a consequence, the anthropogenic impact on mountainous areas raises concerns from many viewpoints. For example, the Alps are crossed by 4200 km of main roads, with 6 million vehicles and 1.24 × 10 11 kg of freights being transported across the Alpine range every year.
Mountain valleys and passes are also often crossed by main transport routes connecting different countries.
0 kommentar(er)
