Climate Change refers to the changes to Earth’s atmosphere, ocean and land caused by human activity. It is the overall warming of the planet, with associated impacts such as extreme heat, protracted drought, flooding and more frequent and intense storms.
Almost half of the energy that reaches Earth from the Sun is absorbed by its atmosphere and oceans. The rest radiates back into space, but long-lasting, heat-trapping gases in the atmosphere slow outgoing radiation and cause a planet to warm. These gases are known as greenhouse gases, and they are mostly created by burning fossil fuels like coal, oil and natural gas. Since the Industrial Revolution began in the late 19th century, global temperatures have been rising fast.
The increase in temperature correlates directly with the rise in greenhouse gases, mainly carbon dioxide (CO2) and methane. Scientists have examined many different types of evidence – including air bubbles trapped in ancient ice and data from tree rings and coral reefs – and have concluded that the Earth is warmer now than it has been for hundreds of thousands of years.
Scientists agree that human activity is driving these changes and that the effects will continue to grow worse. We will see further warming of the atmosphere, ocean and land, along with melting glaciers and ice sheets, rising sea levels and more severe weather events.
Warming is happening everywhere on Earth, but polar regions are especially vulnerable. In the Arctic, summer sea ice is rapidly shrinking and habitats are changing dramatically. In Antarctica, the underlying structure of ice sheets and glaciers is being undermined by thermal expansion as water in them melts. And climate change is having profound impacts on our rivers and lakes, as they warm up.
Climate change affects everyone, but the people most at risk are those who contribute least to its causes and have fewer resources to protect themselves. These include people living in low-income and disadvantaged countries and communities, those who are already vulnerable to health threats such as malnutrition and water scarcity, and people with pre-existing mental illness, who can be more easily harmed by extreme weather events.
The best way to reduce the risks is to cut emissions of greenhouse gases. This can be done through a range of ways, such as switching to clean power, increasing energy efficiency and improving farming techniques. It’s also important to recognise that the climate crisis is a global problem, and that we all have a responsibility to address it. We can do this by promoting sustainable lifestyles, working with governments and other international bodies to implement binding agreements, and raising awareness of the issues. The UN Framework Convention on Climate Change, which has near-universal ratification, is an important step in this process. Its aim is to limit the climate change problem by preventing further warming and enabling nations to adapt to any consequences they can’t avoid. It is the only way we can ensure that the world’s most vulnerable people will be able to live their lives in safety and prosperity.