Climate Change is the term used to describe long-term changes in average weather patterns that have come to characterize local, regional and global climates. Climate change impacts human health and well-being in a variety of ways.
The most significant impact is a warming trend in Earth’s surface temperatures. This has been caused by human activities – particularly the burning of fossil fuels – which increases heat-trapping greenhouse gases in the atmosphere. These gases are mainly carbon dioxide (CO2), but also include methane and other trace gases. The warming effect of these gases is amplified by other human activities that alter the natural environment – such as deforestation and agricultural land-use changes.
In the past few decades, temperatures have been much higher than in any other comparable period in the history of recorded global temperature data. In the words of the Intergovernmental Panel on Climate Change (IPCC), it is “extremely likely” that human activity is responsible for more than half of all modern warming.
Climate change affects many different aspects of life on Earth, including the oceans and other water bodies, terrestrial vegetation, animal species, soil microbes, and ecosystem functions such as energy cycling or nutrient recycling. Ecosystems are complex, and they respond to many different climate change-related forcings, which vary in their strength and timing.
Some of the most important drivers of climate change are changes in ocean currents and wind patterns, shifts in Arctic sea ice extent, long-term changes in atmospheric circulation, the length of the growing season, and rainfall patterns.
Climate Change is causing biodiversity to shrink, and this threatens food security around the world. Changing weather patterns, particularly drought, are making it harder for crops to grow in some regions. This is especially true in the countries and regions that today supply the majority of the world’s food.
Increasingly frequent and intense extreme events have also been linked to climate change. These events can cause physical health problems, such as heat-related illnesses, flooding and water-borne diseases from contaminated floodwaters, and they can harm mental health by leading to loss of loved ones or property, displacement, chronic stress, and feelings of powerlessness.
Scientists estimate that humans are releasing more than 500 billion tons of carbon into the air each year through the use of fossil fuels and other human activities. This is a huge burden on the planet, and will have lasting effects for future generations. Some of this carbon is trapped in the Arctic permafrost, and if it thaws out, it can release methane into the atmosphere – which is 34 times more powerful as a greenhouse gas than CO2 over a century. This is why it is so important to reduce the amount of carbon we are putting into the atmosphere.