Global warming is the long-term heating of Earth’s climate system observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere. The term is frequently used interchangeably with the term climate change, though the latter refers to both human- and naturally produced warming and the effects it has on our planet. It is most commonly measured as the average increase in Earth’s global surface temperature.
Since the pre-industrial period, human activities are estimated to have increased Earth’s global average temperature by about 1 degree Celsius (1.8 degrees Fahrenheit), a number that is currently increasing by 0.2 degrees Celsius (0.36 degrees Fahrenheit) per decade. Most of the current warming trend is extremely likely (greater than 95 percent probability) the result of human activity since the 1950s and is proceeding at an unprecedented rate over decades to millennia.
The largest human influence on climate change has been the emission of greenhouse gases such as carbon dioxide, methane and nitrous oxide. The primary source of these emissions is from burning fossil fuels for electricity, heat and transportation. Greenhouse gases act like a blanket around Earth, trapping energy in the atmosphere and causing it to warm.
The impacts of climate change are already being felt around the world, and are expected to become more severe in the future. These impacts include rising sea levels, more extreme weather events, changes in agricultural yields, and loss of biodiversity.
Global warming may result in the following:
- Flood: As the Earth’s temperature rises, the ice caps and glaciers melt, causing sea levels to rise. This can lead to flooding in coastal areas.
- Cyclone: Climate change can also lead to more extreme weather events, such as cyclones. These events can cause widespread damage and loss of life.
- Decrease in forest productivity: Forests play an important role in absorbing carbon dioxide from the atmosphere. However, as the Earth’s temperature rises, forests are becoming more stressed and less productive. This can lead to a decrease in the amount of carbon dioxide that is absorbed from the atmosphere.
All of these impacts can have a devastating effect on human society and the natural world. It is therefore essential that we take action to reduce greenhouse gas emissions and mitigate the impacts of climate change.