Photosynthesis is the process by which trees absorb carbon dioxide from the atmosphere and store it in their biomass, making them an important tool in mitigating climate change.

Fossilization is the process by which organic matter is converted into fossil fuels over millions of years. Fossil fuels, such as coal, oil, and natural gas, are non-renewable sources of energy that contribute to greenhouse gas emissions.

Deforestation contributes to greenhouse gas emissions by releasing carbon stored in trees into the atmosphere. Trees are also important for carbon sequestration, making deforestation a double threat to the environment.

Hydroelectric power harnesses the power of moving water to generate electricity, making it a renewable energy source.

Deforestation is not a direct cause of ocean acidification. The primary cause is increased levels of carbon dioxide in the atmosphere, which can dissolve in the ocean and lower its pH.