What human activity contributes to increased levels of carbon dioxide in the atmosphere?

The activity that contributes to increased levels of carbon dioxide in the atmosphere is the combustion of fossil fuels. When fossil fuels such as coal, oil, and natural gas are burned for energy, carbon stored in these fuels is released as carbon dioxide gas. This process is a major source of greenhouse gases, contributing significantly to climate change and global warming.

Combustion of fossil fuels occurs in various sectors, including transportation, electricity generation, and industrial processes. As these activities increase, so does the amount of carbon dioxide emitted into the atmosphere. This not only enhances the greenhouse effect but also disrupts the balance of carbon in the carbon cycle.

In contrast, while agricultural practices and deforestation do play roles in carbon emissions and environmental changes, they do not contribute to carbon dioxide levels to the same extent as fossil fuel combustion. Agricultural practices may lead to methane emissions or nitrous oxide, but they are not the primary source of carbon dioxide. Deforestation does release carbon dioxide when trees are cut down, as trees act as carbon sinks, but again, this is a secondary effect compared to the extensive use of fossil fuels. Solar energy, on the other hand, generates energy without emissions of carbon dioxide during its use, supporting cleaner energy initiatives.