Final answer:
Atmospheric carbon dioxide levels are rising due to the burning of fossil fuels and deforestation, disrupting the natural carbon cycle and intensifying the greenhouse effect, leading to global warming and climate change.
Step-by-step explanation:
Understanding the Rising Carbon Dioxide Levels
The observable increase in atmospheric carbon dioxide levels worldwide is largely due to the burning of fossil fuels. The carbon cycle naturally involves the uptake and release of CO₂ through processes such as photosynthesis and cellular respiration. However, human activities, primarily the combustion of fossil fuels and deforestation, have significantly disrupted this balance. The burning of coal, oil, and natural gas for energy and transportation releases vast amounts of carbon dioxide, further exacerbating the greenhouse effect and contributing to global warming. The destruction of forests reduces the planet's capacity to absorb this greenhouse gas, which plants typically sequester during photosynthesis.
Since the Industrial Revolution, the concentration of carbon dioxide has escalated from 280 parts per million to over 400 ppmV. These heightened levels of CO₂ contribute to climate change, with effects including sea level rise, ocean acidification, and changes in global biodiversity. An increase in atmospheric carbon dioxide can boost plant growth in some regions, acting as a 'fertilizer,' but the broader implications of climate change often outweigh this local benefit. Therefore, a shift to renewable sources like hydroelectric, solar, wind, and nuclear power is essential for mitigating further environmental impacts.