CLIMATE WATCH - What's Causing Global Warming?

If the climate changed before humans, how can we be sure that human activities are responsible for the warming that’s happening today?1

First, we can eliminate many of the factors that can cause global climate change.

1)  The sun has been dimming slightly for the last half-century while the Earth heats up, so global warming cannot be blamed on the sun.

2)  Volcanoes can produce CO2, but adding up all the CO2 produced by every volcano on Earth per year gives a number less than 1% of the CO2 produced by burning fossil fuels.      

3) Orbital cycles that produce changes such as ice ages are currently in the wrong phases to account for the current warming, and the changes they cause happen over very long time periods, not a century or two.

Scientists have carried out studies of all the possible "natural" causes.  None can account for the current warming. 

However, CO2 has been known to have a property often called "The Greenhouse Effect" since the 19th century.  

So.........


From: http://solar-center.stanford.edu/sun-on-earth/glob-warm.html


Some useful links:

A short video from Carbon Brief: https://www.youtube.com/watch?v=sKDWW9WlPSc&t=82s

An article by geologist Howard Lee: https://www.quantamagazine.org/how-earths-climate-changes-naturally-and-why-things-are-different-now-20200721/

The UK Met Office: https://www.metoffice.gov.uk/weather/climate-change/causes-of-climate-change

The British Geological Survey: https://www.bgs.ac.uk/discovering-geology/climate-change/what-causes-the-earths-climate-to-change/


More from Carbon Brief:  https://www.carbonbrief.org/analysis-why-scientists-think-100-of-global-warming-is-due-to-humans/






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