Why does climate change matter?
Greenhouse gases can live in our atmosphere for tens or hundreds of years. The gases that are already in our atmosphere are effectively locked in and will contribute to increasing temperatures.
Even if we stop all emissions today, we cannot avoid some level of warming. The amount of warming we will see, beyond what we have already caused, depends on the changes we make.
The United Nations Intergovernmental Panel on Climate Change (IPCC) Special Report on Global Warming of 1.5 degrees Celsius was published in October 2018 and describes the enormous harm that a 2 degrees Celsius is likely to cause compared to a rise of 1.5 degrees. Climate-related risks to health, livelihoods, food security, water supply, human security, and economic growth are projected to increase with global warming of 1.5°C and increase further with 2°C.
It is estimated that, globally, humans need to reduce our CO2eq (carbon equivalent) emissions from the current 6.5 tonnes per person per year to less than 2 tonnes as soon as possible. This will need ambitious action from national and sub national authorities, civil society, indigenous peoples and local communities. Current local and global plans and policies are not going to meet this target.