Dr. Roberts considers threats to the Earth's ozone layer and traces the history of research on the ozone layer. Walter Orr Roberts informal series, "Provocations." Each issue consists of provocative comments related to scientific issues that mostly focus on weather, climate, the sun, or near spac... Show moreDr. Roberts considers threats to the Earth's ozone layer and traces the history of research on the ozone layer. Walter Orr Roberts informal series, "Provocations." Each issue consists of provocative comments related to scientific issues that mostly focus on weather, climate, the sun, or near space, with the aim of creating a forum for discussion. Show less
