Climate Change - Separating Natural Temperature Trends from Human Factors


The Earth's temperature is a response to various factors.

These are called climate forcings.

They are - changes in the gases in the air; changes in the Earth's orbit and rotation (which alters the amount of energy reaching the surface from the Sun); plate movements; ocean currents - and some other thingss.

 Various research groups have investigated the possibility that the current warming could be caused by natural factors.

This kind of research is called an attribution study. The graph below shows the outcome of one study of that kind.




This shows that the natural factors cannot be driving the current warming.

 The warming trend fits what would be expected to be caused by combining the natural factors with the effects of human activity.

 Other attribution studies include 

 "Global temperature evolution 1979–2010" - Foster & Rahmstorf, 2011

 and

 "A probabilistic quantification of the anthropogenic component of twentieth century global warming" - Wigley & Santer, 2012.



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