9.2.2 Human Activities which Contribute to an Increase in Greenhouse Gases in the Atmosphere

Carbon Dioxide (CO₂)

Human activities that increase carbon dioxide levels in the atmosphere include:

• Burning Fossil Fuels: The combustion of fossil fuels, such as coal, oil, and natural gas, for energy production, transportation, and industrial processes releases carbon dioxide.
• Deforestation: Clearing forests for agriculture, logging, or urban development reduces the Earth's capacity to absorb carbon dioxide through photosynthesisThe process by which plants use light energy to produce glucose., leading to increased CO₂ levels.

Methane (CH₄)

Human activities that contribute to methane emissions include:

• Agriculture: Livestock farming, particularly cattle and sheep, produces methane as a byproduct of enteric fermentation, a digestive process in ruminant animals.
• Landfills: Decomposing organic waste in landfills generates methane gas, commonly known as landfill gas.
• Fossil Fuel Production: Methane is released during the extraction, transport, and distribution of fossil fuels, including coal, oil, and natural gas.

Global Climate Change

Based on extensive scientific research and peer-reviewed evidence, many scientists believe that human activities will cause an increase in greenhouse gases, leading to global climate change. The release of greenhouse gases traps more heat in the atmosphere, resulting in rising global temperatures and various impacts on climate patterns, ecosystems, and human societies.

Challenges in Modelling Climate Change

Climate change is a complex and dynamic process that involves numerous factors, interactions, and feedback loops.

• Modelling climate change requires simplifications and assumptions to represent the Earth's complex systems accurately.
• Different models can yield varying predictions and projections, leading to a range of interpretations and opinions in the media.
• It is essential to rely on peer-reviewed research and scientific consensus to understand the most accurate and reliable information about climate change.

Evaluating the Quality of Evidence

When evaluating the quality of evidence presented in reports about global climate change, it is important to consider the credibility and reliability of the sources, the methodology used in data collection and analysis, and the presence of bias or conflicts of interest.

Uncertainties in the Evidence Base

The field of climate science involves uncertainties due to the complexity of Earth's climate system and the limitations of data collection and modelling. Uncertainties can arise from factors such as the availability of long-term data, the complexity of climate interactions, and the challenges of making accurate predictions.

Importance of Peer Review

Peer review is a crucial process in scientific research, where experts in the field critically evaluate and provide feedback on research studies before they are published. Peer-reviewed studies undergo rigorous scrutiny, which helps identify errors, biases, or gaps in research methodology.