What is the strongest evidence that HCFCs are in the stratosphere? A) Chemical reactions predict there should be HCFCs in the upper atmosphere. B) Measurement of chlorine in air samples from the lower atmosphere. C) Measurement of HCFCs in air samples from the stratosphere. D) Satellite measurements of light passing through the atmosphere. Which of the following gases help form the earth’s protective shield? A) Methane B) Radon C) Stratospheric Ozone D) Carbon Dioxide What effect(s) can stratospheric ozone depletion have on the environment? A) Decreased crop yields and damage to marine organisms B) Reduced cataracts and skin cancers C) Decreased ground-level ozone D) Global warming What evidence demonstrates that chlorine in the stratosphere is primarily from man-made chemicals rather than from natural sources such as volcanoes? A) The rise in the amount of chlorine measured in the stratosphere matches the rise in the amount of fluorine, which has different natural sources than chlorine, over the same period. B) The rise in the amount of chlorine measured in the stratosphere matches the rise in ozone-depleting emissions over the same period. C) Samples of air taken from the stratosphere over erupting volcanoes show that volcanoes contribute a small quantity of chlorine to the stratosphere compared to CFCs and HCFCs. D) All of the listed reasons. What is one of the most serious results of damage to the stratospheric ozone layer? A) Increased acid rain B) Increased rates of asthma C) Increased rates of skin cancer in humans D) Higher natural background radioactivity Which type of refrigerant typically has the lowest global warming potential? A) HCFCs B) HFOs C) HFCs