Editing Little Ice Age (section)

==Central England temperature series==

[[File:Central England Temperature Seasonal1.png|thumb|upright=1.8|Seasonal values of Central England temperatures. The top panel shows group [[sunspot]] numbers: the grey area shows the annual values from telescopic observations, the mauve line its 11-year running means, and the green line the values deduced from the abundance of the [[Carbon-14]] [[Cosmogenic nuclide|cosmogenic isotope]] in tree trunks. The second panel shows the winter values of [[Central England temperature]], being the mean for December, January and February. The third panel shows the summer values, being the mean for June, July and August. The bottom panel gives the aerosal [[optical depth]], showing volcanic dust levels, from ice sheet cores. The vertical mauve lines are years in which frost fairs were held on the Thames in London and the vertical orange lines are the years when the ice there was reported as thick enough to walk on. The first cyan line is the date of the removal of the old [[London Bridge]] and wier and the second is the completion of the embankments: both riverine developments that increased the flow and ended Thames freezing events. All data sources are given in reference <ref name="lock1" />]]
The [[Central England temperature]] (CET) is the longest instrumental temperature record in existence anywhere in the world, and extends back continuously from the present day to 1659. Hence it starts in the middle of the Little Ice Age (LIA), however the LIA interval is defined. CET holds some very important implications for our understanding of the LIA. The CET data show that during the LIA there was an increased occurrence of exceptionally cold winters and these years coincided with years when frost fairs were held on the Thames and when exceptionally low temperatures were reported elsewhere in Europe.<ref name="lock1"/> It also agrees well with paleoclimate estimates in average trends.<ref name="owens1">{{Cite journal |last1=Owens |first1=M. J. |display-authors=et al. |date=October 2017 |title=The Maunder Minimum and the Little Ice Age: An update from recent reconstructions and climate simulations |url=https://centaur.reading.ac.uk/74244/ |journal=Journal of Space Weather and Space Climate |language=en |volume=7 |pages=A25 |doi=10.1051/swsc/2017019 |issn=2115-7251 |s2cid=37433045 |doi-access=free|arxiv=1708.04904 }}</ref> However, winters were not unremittingly cold during the LIA in the CET record. For example, the coldest winter (defined by the average temperature for December, January and February) in the whole CET data series is 1684 (the year of one of the most famous frost fairs) yet the fifth warmest winter in the whole CET data series to date occurred just two years later, in 1686. Furthermore, summer temperatures are not greatly depressed during the LIA and when they are these lower temperatures correlate highly with volcanic eruptions.<ref name="lock1" /> Hence the CET data strongly argue that the LIA, at least in Europe, should be regarded as a period of enhanced occurrence of exceptionally cold winters and hence lower average temperatures and not as an interval of unremitting cold.