I’ve been researching the topic of climate change for an essay, but I’m struggling to understand the main causes of it. Could you explain the major causes of global warming, and how human activities have contributed to the current environmental situation? Could you cite some recent sources or studies, too?
Humans contribute to global warming primarily through releasing greenhouse gases into the atmosphere through activities such as burning fossil fuels for energy, deforestation, and intensive farming practices.

1. **Burning Fossil Fuels**: This is the leading cause of global warming. Human activities like driving cars, operating power plants, and operating factories require energy, which typically comes from the combustion of fossil fuels like coal, oil, and gas. During the combustion process, carbon dioxide (CO2), a potent greenhouse gas, is released. Producing electricity and heat is responsible for the largest percentage of global greenhouse gas emissions.

2. **Deforestation**: Trees absorb CO2, reducing the amount in the atmosphere. However, when we cut down or burn trees, that absorbed CO2 gets released back into the atmosphere. Additionally, deforestation for agricultural purposes often entails the burning of vegetation, which releases particulates and monoxides into the atmosphere.
   
3. **Agriculture**: Intensive farming also contributes to global warming. Methane (another potent greenhouse gas) is released by livestock during digestion due to enteric fermentation and is also released from manure. Agriculture, Forestry, and Other Land Use sector produces about 24% of global greenhouse gas emissions according to the Food and Agriculture Organization (FAO).

4. **Industrial Processes**: In certain industries like cement production or in the production of goods like plastic and steel, heavy amounts of CO2 and other greenhouse gases are released. Industrial processes (including the energy required to undertake those processes) contribute significantly towards global warming.

Studies have repeatedly shown the impact of these activities:

- A study published in the journal "Nature Climate Change" shows the impact of fossil fuels on rising global temperatures.
- A report by the Intergovernmental Panel on Climate Change (IPCC) outlines the various ways in which deforestation and land use contribute to global warming.
- A comprehensive study in the journal "Science" examines the contribution of agriculture to greenhouse gas emissions.

Understanding and addressing these causes is crucial to mitigating the detrimental effects of climate change.