Anthropogenic Space Weather

Anthropogenic effects on the space environment started in the late 19th century and reached their peak in the 1960s when high-altitude nuclear explosions were carried out by the USA and the Soviet Union. These explosions created artificial radiation belts near Earth that resulted in major damages to several satellites. Another, unexpected impact of the high-altitude nuclear tests was the electromagnetic pulse (EMP) that can have devastating effects over a large geographic area (as large as the continental United States). Other anthropogenic impacts on the space environment include chemical release ex- periments, high-frequency wave heating of the ionosphere and the interaction of VLF waves with the radiation belts. This paper reviews the fundamental physical process behind these phenomena and discusses the observations of their impacts.Comment: 71 pages, 35 figure

Characteristics of gaseous and particulate air pollutants at four different urban hotspots in Tehran, Iran

This study reports a characterization of outdoor gaseous and particulate pollutants and their associated health effects in four different urban hotspots in Tehran, Iran during winter and summer. Buses, taxis, and cars are prominent sources of toxic pollutants in Tehran. There is a significant level of exposure to emissions from diesel buses in bus terminals, especially with boarding, disembarking, and waiting. Mean concentrations (μg/m3) in summer and winter, respectively, ranged from 10 to 20.67 and 17�21 for PM1, 52.50�79.19 and 58.33�85.33 for PM2.5, 64.50�102 and 78.83�125.83 for PM7, 130.17�204.67 and 157�231.67 for PM10, 261�409.50 and 305.83�458.83 for TSP, and 372.50�418.33 vs. 351.27�373.47 for CO2 (ppm). Particulate concentrations were higher in winter, especially the first three days of the week, assisted in part by the shallower mixing layer height as compared to summer. Mean hazard quotient (HQ) values for both PM2.5 and PM10 in both seasons for bus terminals in three scenarios ranged between 0.81 and 4.96, which exceeded reference levels (1 < HQ). The results of this study have implications for public health, especially in dense traffic areas. © 2021 Elsevier Lt