data/sample_docs/climate_change.txt

Climate Change

Climate change refers to long-term shifts in global temperatures and weather patterns.
Since the industrial revolution, human activities have been the main driver of 
climate change, primarily through the burning of fossil fuels.

Greenhouse Effect:
The greenhouse effect is a natural process that warms Earth's surface. Greenhouse 
gases in the atmosphere trap heat from the sun. Without the greenhouse effect, 
Earth's average temperature would be about -18°C instead of the current 15°C.

Major Greenhouse Gases:
- Carbon dioxide (CO2): Largest contributor, from burning fossil fuels
- Methane (CH4): 25 times more potent than CO2, from agriculture and landfills
- Nitrous oxide (N2O): 298 times more potent than CO2, from fertilizers
- Fluorinated gases: Synthetic gases from industrial processes

Key Statistics:
- Global average temperature has risen by 1.1°C since pre-industrial times
- Atmospheric CO2 levels reached 421 ppm in 2023, highest in 800,000 years
- Sea levels have risen by about 21-24 cm since 1880
- Arctic sea ice is declining at about 13% per decade

Effects of Climate Change:
- Rising sea levels threatening coastal communities
- More frequent and intense extreme weather events
- Ocean acidification affecting marine ecosystems
- Changes in precipitation patterns and water availability
- Shifts in plant and animal habitats and migration patterns
- Increased risk of wildfires and droughts

International Agreements:
The Paris Agreement was adopted in 2015 by 196 parties at COP21. Its goal is to 
limit global warming to 1.5°C above pre-industrial levels. Countries submit 
Nationally Determined Contributions (NDCs) outlining emission reduction targets.

The Intergovernmental Panel on Climate Change (IPCC) was established in 1988. 
It provides scientific assessments on climate change, its impacts, and potential 
response strategies.