Climate change is more than just an increase in global temperatures – it’s the impact of changing weather patterns on things that we depend upon and value, like water, energy, wildlife, agriculture, ecosystems and human health. Human activities are driving climate change and it is already causing impacts around the world, such as sea level rise, hotter and more frequent heat waves and droughts, wildfires, floods and storms.
Climate changes are caused by a combination of natural and human factors, but the majority of warming since 1950 has been driven by human emissions of heat-trapping gases. These are known as greenhouse gases and they include carbon dioxide, methane, nitrous oxide and chlorofluorocarbons. They are produced by burning fossil fuels for energy, clearing forests, land-use change, livestock and some industrial processes.
As these gases are emitted into the atmosphere, they cause the Earth to warm by blocking some of the sun’s radiation from escaping into space. This effect is called the greenhouse effect and it’s important because it helps to sustain life on Earth.
But it can also lead to some very bad outcomes, such as melting glaciers and ice sheets, rising sea levels, more frequent and severe heat waves and extreme weather events and decreasing crop yields. The effects of climate change are already being felt in every corner of the planet, but some communities are at greater risk than others.
This is because, as the climate changes, some people are more likely to be exposed to harmful impacts and not be able to adapt to them. This includes those living in low-income communities, some communities of color, people with limited English proficiency, immigrants, children and pregnant women, older adults, vulnerable occupational groups and people with medical conditions.
Humans are the main driver of global temperature increases and the most significant contributor to current and future climate change. Scientists have found that the average global temperature has risen by about 1.98°F offsite link (1.1°C) since 1901. The anthropogenic contribution to that warming has been calculated to be about 48%.
The effects of climate change will have an impact on all regions of the globe and are likely to have profound implications for the quality of life. These impacts are already being experienced by many communities across the United States, for example heat waves, flooding, wildfires and extreme weather events that disrupt or destroy lives and property.
The good news is that we can slow and reverse the harmful effects of climate change by making changes to how we produce and use energy, food, transportation and build our cities and towns. For starters, we can stop using fossil fuels. We can shift to clean energy sources, such as solar power and wind turbines. We can make a commitment to recycle and reduce waste, and we can invest in green products and services. We can also support legislation that will help to cut the production of climate change-causing greenhouse gases. This will require all of us to work together.