Human activities primarily contributing to climate change include:

1. Burning Fossil Fuels: The combustion of coal, oil, and natural gas for energy is the largest source of greenhouse gas emissions. This releases carbon dioxide (CO2) and other pollutants into the atmosphere.
2. Deforestation: Clearing forests for agriculture, logging, and urban development reduces the number of trees that absorb CO2. This contributes to higher atmospheric CO2 levels.
3. Industrial Processes: Manufacturing, cement production, and other industrial activities release greenhouse gases like CO2, methane (CH4), and nitrous oxide (N2O).
4. Agricultural Practices: Livestock digestion (which produces methane), rice paddies (which emit methane), and the use of synthetic fertilizers (which release nitrous oxide) all contribute to greenhouse gas emissions.
5. Waste Management: Landfills produce methane as organic waste decomposes. Improper disposal and incineration of waste also release greenhouse gases.
6. Transportation: Vehicles powered by fossil fuels emit CO2 and other pollutants. Air travel, shipping, and road transportation are significant contributors.
7. Urbanization: As cities grow, energy demands increase, leading to higher emissions from buildings, transportation, and infrastructure development.

These activities have intensified since the Industrial Revolution, causing a rapid increase in greenhouse gas concentrations in the atmosphere. This accumulation traps heat, leading to global warming and climate change, with far-reaching impacts on ecosystems, weather patterns, sea levels, and human societies worldwide. Addressing these activities through mitigation strategies is crucial to limiting future climate change and its adverse effects.