The Earth is naturally warmed by rays from the sun which pass through the atmosphere to the surface.
Much of this radiation is reflected back into space, but gases in the atmosphere – so-called greenhouse gases – create a thermal blanket, trapping some of this radiation.
This has kept the Earth at the right temperature to sustain life. The problem now, however, is that rising levels of greenhouse gases, primarily carbon dioxide, are trapping more radiation, pushing global temperatures up.
Some argue that rising temperatures are part of natural meteorological cycles, but the conclusion based on an overwhelming amount of scientific evidence is inescapable – human activity is increasing global temperatures.
Some also joke that increases in temperature are welcome, a new Mediterranean-style climate allowing us to get a better tan and grow new flowers, vegetables and fruit in our gardens.
The reality is that increases in temperatures might be pleasant initially, but will quickly give way to increasingly violent weather extremes here and abroad that will have a devastating impact on billions of people.
So the goal isn't really to save the planet, but ourselves - the Earth would merrily continue on without us if we were gone…
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