title: Meteorological effects of the solar eclipse of 20 March 2015: analysis of UK Met Office automatic weather station data and comparison with automatic weather station data from the Faroes and Iceland.
abstract: Here, we analyse high-frequency (1 min) surface air temperature, mean sea-level pressure (MSLP), wind speed and direction and cloud-cover data acquired during the solar eclipse of 20 March 2015 from 76 UK Met Office weather stations, and compare the results with those from 30 weather stations in the Faroe Islands and 148 stations in Iceland. There was a statistically significant mean UK temperature drop of 0.83±0.63°C, which occurred over 39 min on average, and the minimum temperature lagged the peak of the eclipse by about 10 min. For a subset of 14 (16) relatively clear (cloudy) stations, the mean temperature drop was 0.91±0.78 (0.31±0.40)°C but the mean temperature drops for relatively calm and windy stations were almost identical. Mean wind speed dropped significantly by 9% on average during the first half of the eclipse. There was no discernible effect of the eclipse on the wind-direction or MSLP time series, and therefore we can discount any localized eclipse cyclone effect over Britain during this event. Similar changes in air temperature and wind speed are observed for Iceland, where conditions were generally clearer, but here too there was no evidence of an eclipse cyclone; in the Faroes, there was a much more muted meteorological signature.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'.
authors.affiliation: Department of Geography, University of Sheffield, Sheffield S10 2TN, UK ehanna@sheffield.ac.uk.
authors.forename: Edward
authors.identifier: http://orcid.org/0000-0002-8683-182X
authors.initials: E
authors.lastname: Hanna
authors.affiliation: Met Office, Edinburgh EH11 3XQ, UK.
authors.forename: John
authors.initials: J
authors.lastname: Penman
authors.affiliation: Icelandic Met Office, 108 Reykjavik, Iceland.
authors.forename: Trausti
authors.initials: T
authors.lastname: Jónsson
authors.affiliation: Department of Geography, University of Sheffield, Sheffield S10 2TN, UK.
authors.forename: Grant R
authors.initials: GR
authors.lastname: Bigg
authors.affiliation: Icelandic Met Office, 108 Reykjavik, Iceland.
authors.forename: Halldór
authors.initials: H
authors.lastname: Björnsson
authors.affiliation: Deildin fyri infrakervi/Infrastructure Department, Landsverk, FO-110 Tórshavn, Faroes.
authors.forename: Sølvi
authors.initials: S
authors.lastname: Sjúrðarson
authors.affiliation: Deildin fyri infrakervi/Infrastructure Department, Landsverk, FO-110 Tórshavn, Faroes.
authors.forename: Mads A
authors.initials: MA
authors.lastname: Hansen
authors.affiliation: Danish Meteorological Institute, DK-2100 Copenhagen Ø, Denmark.
authors.forename: John
authors.initials: J
authors.lastname: Cappelen
authors.affiliation: Department of Geography, University of Sheffield, Sheffield S10 2TN, UK.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Bryant
keywords: meteorology; pressure; solar eclipse; temperature; wind