Alternative small scale meteorology input to a chemical transport ...

2.1. Historical remarks
CHAPTER 2. BACKGROUND INFORMATION
Ambient air composition over the Earth has undergone several changes throughout the
years. Anthropogenic activities, especially since the 17-th century, when coal began to replace
wood as the primary source of energy, have played a significant role in the earth’s atmosphere
balance. These anthropogenic pollutants have often generated locally unhealthful air quality with
short term episodic effects or difficult to predict adverse effects. The emergence of petroleum
products in the twentieth century has characterized a new industrial revolution and the
recognition that petroleum products are responsible for the so called “photochemical” summer
smog, like the smog in the Los Angeles area. The last decades of the twentieth century have
been characterized by a growing interest in long range air pollution transport phenomena and
global effects.
These days, the society is showing increasing interest towards the air quality and the
environment. In response, air quality modeling has increasingly become a more important part of
the study of the environment. Modeling, like monitoring, is not the solution to the air pollution
problem. But modeling provides a powerful tool for studying the environment and, with the
advance of science, to better represent the real processes in the atmosphere.
2.2. The “one atmosphere” perspective
Comprehensive air quality modeling of large domains started in the late 1970's. The
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