Who killed Spring 2013? Suspect #3: The Sun!?

March 27, 2013 — 1 Comment

Whilst the output of the sun varies very little (it is called “solar constant” for good reason), various other measurable factors such as solar magnetic activity, sunspot cycles and irradiance have all been raised as possible suspects for the crime of killing Spring 2013 across the northern hemisphere. Low solar energy receipt has been correlated with a colder northern hemisphere by influencing northern blocking.  A low point in sunspot activity called the “Maunder Minimum” has been closely associated with the onset of the Little Ice Age when the Thames regularly froze over every winter. Solar flares have been associated with warming of the upper atmosphere which has, in turn, been linked to higher pressure in the polar regions.
Links (correlations) have also been found between sunspot cycles and the extent of sea ice in the North Atlantic. Nevertheless, correlating solar activity and the climate on Earth has been surprisingly difficult to pin down.  Importantly, correlating sunspot activity with any climatic variable does not indicate a causal link. Wiggly lines on graphs may coincide but does one cause the other?  It is all still full of controversy. Even the IPCC recognise that, whilst there is some evidence to suggest a link between warming and increases in solar activity between 1750 and 1950, the measurable increase in global warming far exceeds any change in solar output. Since 1979, when measurements of sun output started in space, there has been no long-term significant increase in solar energy.  Sunspots are frequently hauled in to account for weather and climate changes but the evidence is hard to pin on them and almost entirely circumstantial!  Sunspots are intertwined with the greatest driver of our weather, the Sun, however, with such flimsy evidence the jury is still out on this suspect. With other major suspects under questioning it seems reasonable to let solar energy go free.

Climate Cluedo!

Trackbacks and Pingbacks:

  1. Climate Cluedo! Who killed Spring 2013? « Reigate Grammar School Weather Station - March 27, 2013

    […] Solar activity: sunspot cycles […]

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s