4. According to the lectures, Los Angeles is a city with one of the highest levels of air pollution globally. a) In the box below draw a cross-sectional diagram of the city of Los Angeles and explain why its location is one of the key reasons why LA is subject to such high levels of air pollution. In your answer, discuss radiation inversion, subsidence inversion and lengths of occurrence of temperature inversion (e.g. hours, days or months). b) Consider that the urban area of Los Angeles covers an area of 550 km2 that is subject to an atmospheric inversion with an elevation of 250 m above ground level. The atmospheric carbon monoxide concentration at the start of the inversion was 1.3 ug m 3. The combined air emissions from all factories in the urban area include carbon monoxide which is emitted at a rate of 25 kg h-1. Estimate how long the factories can continue their air emissions before the carbon monoxide concentration in the air shed exceeds 11 ug m3. In your estimate assume complete mixing, no exchange of air with areas outside of the urban area and that the carbon monoxide emissions behave conservatively. 4. According to the lectures, Los Angeles is a city with one of the highest levels of air pollution globally. a) In the box below draw a cross-sectional diagram of the city of Los Angeles and explain why its location is one of the key reasons why LA is subject to such high levels of air pollution. In your answer, discuss radiation inversion, subsidence inversion and lengths of occurrence of temperature inversion (e.g. hours, days or months). b) Consider that the urban area of Los Angeles covers an area of 550 km2 that is subject to an atmospheric inversion with an elevation of 250 m above ground level. The atmospheric carbon monoxide concentration at the start of the inversion was 1.3 ug m 3. The combined air emissions from all factories in the urban area include carbon monoxide which is emitted at a rate of 25 kg h-1. Estimate how long the factories can continue their air emissions before the carbon monoxide concentration in the air shed exceeds 11 ug m3. In your estimate assume complete mixing, no exchange of air with areas outside of the urban area and that the carbon monoxide emissions behave conservatively