What is the main environmental issue caused by increased emissions of carbon dioxide?

Increased emissions of carbon dioxide are primarily linked to global warming, which is a significant environmental issue. The rise in carbon dioxide levels in the atmosphere contributes to the greenhouse effect, where greenhouse gases trap heat from the sun. This process results in an increase in the Earth's average temperature, leading to various climate changes.

Global warming can cause severe weather events, rising sea levels, and shifting ecosystems, all of which pose threats to natural habitats and human societies. The increased temperature can result in the melting of polar ice and glaciers, exacerbating issues like flooding in coastal areas and impacting freshwater sources.

While ozone layer depletion, loss of biodiversity, and acid rain are serious environmental concerns, they are not directly caused by increased carbon dioxide emissions. Ozone layer depletion is primarily associated with substances like chlorofluorocarbons (CFCs), loss of biodiversity can result from various factors including habitat destruction and pollution, and acid rain is mainly related to sulfur dioxide and nitrogen oxides from industrial processes. Thus, global warming remains the most relevant issue directly consequent to rising carbon dioxide levels.