Air pollution is one of the most important problems in urban areas that always threaten citizen's health. Photochemical smog is one of the main factors of air pollution in large cities like Tehran. Usually smog is not only a part of nature, but is being analyzed as an independent matter, which highly affects on the nature. It has been used as relationship between atmospheric elements such as te...

Global warming has become a major threat to life on the earth, and recognizing its impacts can definitely be useful in controlling mitigating adverse effects. In this study, time series variations air temperature indices (frost days, Tmin, Tmax, Tmean, Tminmin, Tmaxmax, Tsoil-min), De Martonne aridity index (IDM), total precipitation were investigated using long-term meteorological data (1960–2...

Cholera is an acute infectious disease with high mortality if left untreated. Historically, between the 19(th) and 20(th) centuries seven great pandemics of cholera occurred and worldwide, thousands of people died. Based on an old theory, cholera was considered an air-born disease and the emergence of its outbreaks were attributed to bad weather or miasma. However later in the 18(th) century, B...

Airborne particulate matter with a diameter of 2.5 microns or less (PM2.5), as well as slightly bigger particles (PM10), arrive from the westerly direction and collect in the city centre of Tehran, the capital of Iran. The statistical characteristics and daily trend of the air quality index (AQI) in Theran were studied over an 11-year period (2002- 2012). Various statistical analyses were appli...