answer: #Person1# and #Person2# are talking about pollution. They think exhaust fumes contribute to water pollution and air pollution. Then they talk about the greenhouse effect and global warming. #Person2# thinks some people are pleased with global warming, while #Person1# thinks it's because people seem to make jokes to deal with unfortunate situations.
documents: #Person1#: The air quality in this city is horrendous. The pollution levels are so high that we are not supposed to go outside with a face mask again!
  #Person2#: Exhaust fumes from vehicles cause a great deal of damage to the environment.
  #Person1#: On top of that, there are a few large chemical factories in the suburbs, which are contributing to the high pollution levels in the water and the air in this city.
  #Person2#: As much as I love this city, I think I'm going to find a greener city to live in. Living in a polluted city like this just can't be good for my health.
  #Person1#: I know what you mean. However, there are so few places left that have not been affected by global warming. If it's not the pollution, then it's the natural disasters, deforestation, or the greenhouse effect.
  #Person2#: What is the greenhouse effect exactly?
  #Person1#: It's the gradual rise in the earth's temperature.
  #Person2#: I see, so it's similar to global warming?
  #Person1#: They're related to one another, yes.
  #Person2#: I heard that some people in England are pleased with the fact that the climate is becoming warmer because it's making their towns a more pleasant place to live.
  #Person1#: People joke about the benefits of the increase in temperature, but it's not all good news. They've been experiencing a lot of deadly storms there as well.
  #Person2#: People always seem to make jokes as a way to deal with unfortunate situations.
  #Person1#: I think if everyone pitches in, the world will be a better place.