Meteorological responses in the atmospheric boundary layer over southern England to the deep partial eclipse of 20 March 2015

Abstract

A wide range of surface and near-surface meteorological observations were made at the University of Readings Atmospheric Observatory in central southern England (latitude 51.441° N, longitude 0.938°W, altitude 66m above mean sea level) during the deep partial eclipse on the morning of 20 March 2015. Observations of temperature, humidity, radiation, wind speed and direction, and atmospheric pressure were made by computerized logging equipment at 1 Hz, supplemented by an automated cloud base recorder sampling at 1 min intervals and a high-resolution (approx. 10m vertical interval) atmospheric sounding by radiosonde launched from the same location during the eclipse. Sources and details of each instrumental measurement are described briefly, followed by a summary of observed and derived measurements by meteorological parameter. Atmospheric boundary layer responses to the solar eclipse were muted owing to the heavily overcast conditions which prevailed at the observing location, but instrumental records of the event documented a large (approx. 80%) reduction in global solar radiation, a fall in air temperature of around 0.6°C, a decrease in cloud base height, and a slight increase in atmospheric stability during the eclipse. Changes in surface atmospheric moisture content and barometric pressure were largely insignificant during the event. This article is part of the themed issue Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse.