Answer:
The emission of certain substances to the atmosphere produces a greenhouse effect contributing to the global warming. Their origin is diverse. In some instances, they have a natural origin, as is the case of methane generated by living organisms, in particular in the oceans.
However some substance are not naturally produced, some are emitted through human activities. Such as vehicles smoke, pollution and more. Especially burning fossil fuel to make electricity. As the practice of burning fossil fuels grows, so does the amount of carbon dioxide emitted to the atmosphere.
All the chemical and substances we emitted to the atmosphere contribute to the already worsening climate change.
