<human>:  What are the causes of climate change?
<bot>: The primary causes of climate change are increasing levels of greenhouse gases in the atmosphere, primarily from the burning of fossil fuels and from deforestation. Other causes include changes in the Earth's orbit, changes in the amount of solar radiation, and natural climate variability. Human activities such as burning coal, oil, and gas, and deforestation are increasing the concentration of heat-trapping gases in the atmosphere and amplifying the natural greenhouse effect, resulting in climate change.