The graph above not only shows the scientific measurements, but it also underscores the fact that humans have a great capacity to change the climate and thereafter, the planet. The problems truly begin when GHG levels get too high, because of our activities.
Since the Industrial Revolution in the 18th Century, the concentration of GHGs in the atmosphere has been increasing significantly, mainly due to the burning of fossil fuels. Higher concentration’s of GHGs in the atmosphere means that less heat is able to escape into space and is instead being trapped in our atmosphere by these gases, heating up the Earth’s surface and its lower atmosphere more and more. This results in a long term trend of increasing average global temperature, or in other words, global warming.
Even small changes in the average global temperature can cause major and dangerous shifts in climate and weather such as; changes in precipitation patterns, increased prevalence of droughts, heat waves, and other extreme weather. These changes are referred to as climate change.
Since the pre-industrial period, human activities are estimated to have increased Earth’s global average temperature by about 1°C, and if that doesn’t seem like much to you, just consider the difference between 0 and 1°C… that 1°C means the difference between ice and water.