The Earth’s temperature is rising — a lot. It’s warmer than it was in the late 1800s and is warmer than any time in 100,000 years.
Climate change affects every living creature, although some are impacted more than others. It is especially harmful to poor people, communities of color, indigenous populations, and the oceans, where it’s causing severe and dangerous impacts.
A warming world means higher sea levels and more flooding, droughts and heat waves. It also leads to wildfires, landslides and extreme rainfall, all of which can lead to disease and death. A warmer planet also makes hurricanes more destructive and leads to the loss of coral reefs and melting ice sheets, which contribute to sea level rise.
The warming of the atmosphere is driven by human activities, such as burning fossil fuels, deforestation, and agricultural practices. These activities add about seven billion metric tons of carbon dioxide to the air each year, which is causing the climate to warm.
Scientists estimate that reducing greenhouse gas emissions can limit the global average temperature increase to less than 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels. That’s a crucial goal of the 2015 Paris Agreement adopted by world leaders.
But the science is clear that even a few more degrees will lead to major risks to people, ecosystems and economies. The risk of unchecked warming includes the possibility of irreversible changes in natural systems, like disappearing polar bears or a mass die-off of fish. It also could trigger a series of tipping points, where warming causes irreversible changes, including the loss of some species and irreversible shifts in the balance of the Earth’s carbon cycles.
Many of these risks can be influenced by climate policy, but the pace at which the Earth warms in the future is mostly determined by how much greenhouse gases are released and how long they remain in the air. Uncertainties around the rate of future global warming include natural influences on the climate system, such as water vapor and ice feedbacks, ocean circulation changes, and other unpredictable factors.
Those who produce the most greenhouse gas emissions are largely responsible for the climate crisis, and they must act first. But the climate impacts of their choices are felt by everyone on Earth, disproportionately in poor countries that have contributed the least to climate change but face the greatest risks from its consequences. Those countries need three to six times as much financial help to adapt to climate change and switch to non-polluting energy sources as rich nations, according to the IPCC report. They also need to take action soon. The report concludes that if they don’t, their citizens will be up to 15 times more likely to suffer the worst effects of climate change. The IPCC is urging all nations to speed up their response to climate change. Read the full report. The Associated Press’s Fabiano Maisonnave and Fabiano Borenstein contributed to this report.