Clim. Past, 12, 2087–2106, 2016 www.clim-past.net/12/2087/2016/ doi:10.5194/cp-12-2087-2016 © Author(s) 2016. CC Attribution 3.0 License. Jens Esmark’s Christiania (Oslo) meteorological observations 1816–1838: the first long-term continuous temperature record from the Norwegian capital homogenized and analysed Geir Hestmark1 and Øyvind Nordli2 1Centre for Ecological and Evolutionary Synthesis, CEES, Department of Biosciences, Box 1066 Blindern, University of Oslo, 0316 Oslo, Norway 2Norwegian Meteorological Institute (MET Norway), Research and Development Department, Division for Model and Climate Analysis, P.O. Box 43 Blindern, 0313 Oslo, Norway Correspondence to: Geir Hestmark (
[email protected]) Received: 1 June 2016 – Published in Clim. Past Discuss.: 20 June 2016 Revised: 17 October 2016 – Accepted: 19 October 2016 – Published: 18 November 2016 Abstract. In 2010 we rediscovered the complete set of me- and 2012 by the Astronomical Observatory at the University teorological observation protocols made by Jens Esmark of Oslo and the Norwegian Meteorological Institute (MET (1762–1839) during his years of residence in the Norwegian Norway) (Nordli et al., 2015). Previous to 1837, long-term capital of Oslo (then Christiania). From 1 January 1816 to 25 observations of the Oslo weather were known to have been January 1839, Esmark at his house in Øvre Voldgate in the made by Jens Esmark (1762–1839), professor of mining sci- morning, early afternoon and late evening recorded air tem- ences at the University of Oslo (then Christiania). A first re- perature with state-of-the-art thermometers. He also noted air analysis of Esmark’s observations was made by meteorolo- pressure, cloud cover, precipitation and wind directions, and gist B.