Climate change may be due to natural internal processes or external forcings such as modulations of the solar cycles, volcanic eruptions and persistent human-induced changes in the composition of the atmosphere, ocean or in land use.
“Anthropogenic” or “human-induced climate change” results from human activities which are already affecting many weather and climate extremes in every region across the globe. These can include:
• burning of fossil fuels,
• land use and land use changes,
• livestock management,
• waste management, and
• industrial processes.
According to IPCC’s Sixth Assessment Report, human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming. The 10-year average global surface temperature for 2011-2020 is estimated to be 1.1 °C above the 1850-1900 pre-industrial baseline (IPCC AR6 Synthesis Report).
Human-induced climate change has led to widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere, affecting many weather and climate extremes in every region across the globe and causing widespread adverse impacts and related losses and damages to nature and people.
Global greenhouse gas emissions have continued to increase, with unequal historical and ongoing contributions arising from unsustainable energy use, land use and land-use change, lifestyles and patterns of consumption and production across regions, between and within countries, and among individuals. Only with deep, rapid and sustained reductions in greenhouse gas emissions can we limit the temperature increases and avoid the worst impacts of climate change. (Source: IPCC Synthesis Report).