Climate Change refers to the long-term average changes in Earth’s temperature, atmospheric composition and weather patterns. This change has been caused primarily by human activities that increase the levels of heat-trapping greenhouse gases in the atmosphere. These gases warm the planet by trapping some of the sun’s heat and stopping it from escaping into space. The most common greenhouse gas is carbon dioxide, produced by burning fossil fuels, deforestation and some kinds of industrial processes.
Increasing temperatures cause all sorts of problems. They lead to heat waves, droughts, floods and severe wildfires. They cause glaciers and ice sheets to melt, and they raise sea levels. They make the oceans more acidic and disrupt wildlife habitats. In addition, they alter the flow of water around the world and alter weather patterns, resulting in more extreme rainfall events.
Climate change threatens human health and well-being by affecting our food, air and water. It has already harmed hundreds of millions of people worldwide. These people include poorer nations, low-income communities and disadvantaged groups who cannot afford to protect themselves against the effects of climate change. In fact, climate change is causing a growing divide between those who can afford to adapt to its impacts and the billions of people who cannot.
The impacts of climate change are expected to worsen, particularly for the most vulnerable people in developing countries. These people will have the least ability to pay for the necessary adaptations and will suffer most from the increased risk of hunger, disease and displacement resulting from climate change. This is because the countries and communities that contribute most to climate change have the least capacity to respond to it.
The scientific community agrees that the current changes to our climate are largely due to human activity, and it is clear that we need urgent action to limit global warming to a level that can be safely supported by the planet’s ecosystems. In a series of UN reports, thousands of scientists and government reviewers have agreed that limiting global warming to 1.5°C would help avoid the worst climate impacts and maintain a livable climate. Taking this action will require all nations to work together. However, the nations that produce the most emissions should reduce their carbon footprints first. This should be done through a combination of policies, including taxes, regulations, incentives and investments in clean energy. To see how climate change is affecting the world, click on a region below. The Northeast is particularly affected by extreme temperatures, flooding and wildfires. These impacts threaten infrastructure, agriculture, wildlife habitats and biodiversity. They also challenge the region’s capacity to adapt, with varying degrees of difficulty across states and communities.