Chapter 21: Problem 33
Describe three human activities that generate carbon dioxide. List two major mechanisms for the uptake of carbon dioxide.
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Fossil Fuels
The combustion of fossil fuels for electricity, heating, and transportation is the largest source of greenhouse gas emissions globally. The energy released during combustion comes from breaking the chemical bonds in these substances, turning potential energy into usable energy. However, this also results in CO2, a major contributor to the greenhouse effect, which traps heat in the Earth’s atmosphere.
Efforts to reduce fossil fuel emissions include using alternative energy sources, increasing energy efficiency, and capturing CO2 emissions before they escape into the atmosphere. Transitioning to renewable energy sources such as solar, wind, and hydroelectric power can help decrease reliance on fossil fuels.
Photosynthesis
During photosynthesis, these organisms take in CO2 and water and, with the help of sunlight, transform them into glucose (a sugar) and oxygen. The chemical equation for photosynthesis can be represented as:
\[ 6CO_2 + 6H_2O + light \rightarrow C_6H_{12}O_6 + 6O_2 \]
This process not only supplies oxygen, which is crucial for life on Earth, but it also serves as a critical natural mechanism for reducing CO2 in the atmosphere. Although deforestation and land-use changes threaten this balance, reforestation and sustainable practices in agriculture can help bolster the role of photosynthesis in carbon uptake.
Ocean Absorption
Oceans absorb CO2 directly from the atmosphere when surface waters come in contact with the air. Additionally, marine organisms like phytoplankton utilize CO2 for photosynthesis through a process known as the biological pump. This not only helps in reducing atmospheric CO2 but also forms the base of the marine food chain.
While the ocean's ability to absorb CO2 is beneficial, it also leads to increased ocean acidity, which can harm marine life and ecosystems. Ocean acidification affects calcifying organisms such as corals, mollusks, and some plankton species critical for oceanic biodiversity and health.
Strategies to improve ocean health and CO2 absorption include protecting marine habitats, restoring coastal ecosystems like mangroves and seagrasses, and reducing other human-induced pressures on marine environments.