Respostas
Resposta:
What is climate change?
The planet's climate has constantly been changing over geological time, with significant fluctuations of global average temperatures.
However, this current period of warming is occurring more rapidly than any past events. It has become clear that humanity has caused most of the last century’s warming by releasing heat-trapping gases—commonly referred to as greenhouse gases—to power our modern lives. We are doing this through burning fossil fuels, agriculture and land-use and other activities that drive climate change. Greenhouse gases are at the highest levels they have ever been over the last 800,000 years. This rapid rise is a problem because it’s changing our climate at a rate that is too fast for living things to adapt to.
Climate change involves not only rising temperatures, but also extreme weather events, rising sea levels, shifting wildlife populations and habitats, and a range of other impacts.
What causes climate change?
There is an overwhelming scientific consensus that global warming is mostly man-made: 97% of climate scientists have come to this conclusion.
One of the biggest drivers by far is our burning of fossil fuels – coal, gas and oil – which has increased the concentration of greenhouse gases – such as carbon dioxide – in our atmosphere. This, coupled with other activities like clearing land for agriculture, is causing the average temperature of our planet to increase. In fact, scientists are as certain of the link between greenhouse gases and global warming as they are of the link between smoking and lung cancer.
This is not a recent conclusion. The scientific community has collected and studied the data on this for decades. Warnings about global warming started making headlines back in the late 1980s.
In 1992, 165 nations signed an international treaty, the UN Framework Convention on Climate Change (UNFCCC). They have held meetings annually ever since (called “Conference of the Parties” or COP), with the aim of developing goals and methods to reduce climate change as well as adapt to its already visible effects. Today, 197 countries are bound by the UNFCCC.