- A recent study that analyzed atmospheric pressure and temperature data for the period 1979-2012 has indicated that half of global warming has occurred not by greenhouse gases but by natural viability of atmospheric temperatures.
- This was particularly with respect to the warming observed in north eastern Canada and Greenland.
- In Greenland and north eastern Canada, part of the warming is caused by Rosby train of waves that originate in the central tropical Pacific Ocean due to abnormally high sea surface temperatures and carry warm air to these regions.
- Another factor responsible for the warming is the North Atlantic Oscillation (NAO) which is the leading mode of circulation variability in the North Atlantic region. A negative trend has been observed in the NAO for the last 30 yrs.
- Read at: http://www.thehindu.com/todays-paper/tp-features/tp-sci-tech-and-agri/when-climate-change-is-not-fully-responsible-for-warming/article5987670.ece
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