What percentage of carbon dioxide released by humans is absorbed by the ocean and land biosphere?

The correct answer highlights a key aspect of the global carbon cycle, specifically how carbon dioxide (CO2) emissions due to human activities are managed by natural systems. Approximately 50% of the CO2 released by human activities is absorbed by the oceans, while the remaining 50% is absorbed by the land biosphere, which includes forests, soils, and other terrestrial ecosystems.

This balance is crucial for understanding climate change and its impacts, as it shows that natural systems play a significant role in mitigating the effects of greenhouse gas emissions by sequestering carbon. The oceans absorb CO2 through a variety of processes, including diffusion at the water's surface and biological processes that incorporate CO2 into marine organisms. Similarly, terrestrial ecosystems capture CO2 through photosynthesis, where plants convert CO2 into biomass.

The other options do not accurately represent the distribution of CO2 absorption. For instance, stating that 44% is absorbed by the ocean or 56% by the land biosphere misrepresents the balance, while the option indicating that 100% is absorbed into the atmosphere overlooks the crucial role of natural carbon sinks in regulating atmospheric CO2 levels. Understanding the correct percentages is vital for effective climate strategy formulation and analyzing the role of mitigation efforts.