GLOBAL EARLY INSTRUMENTAL CLIMATE DATA DIGITIZED BY THE CLIMATOLOGY GROUP, INSTITUTE OF GEOGRAPHY, UNIVERSITY OF BERN

Lead Author: Yuri Brugnara
Contact: Stefan Brönnimann (stefan.broennimann@giub.unibe.ch)
License: CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)
Funding: ERC PALAEO-RA (Grant ID 787574)
Version: 1.0 (06-Apr-2021)
DOI: https://doi.org/10.5072/91

For the inventory of the stations see file Inventory_PALAEO-RA_digi.csv


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Notes on Station Exchange Format
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The format (SEF) documentation is available at https://datarescue.climate.copernicus.eu/st_formatting-land-stations.

HEADER METADATA
The following additional metadata are included in the header of the SEF files:
- name of observer(s)
- correction for local gravity (PGC) and for temperature (PTC) applied to pressure measurements (Yes/No)
- observation times as reported in the source (for monthly means, if available)
- calendar (if different from Gregorian, see below)
- description and height of instrument (if available)

JULIAN CALENDAR
78 monthly series (27 pressure, 34 temperature, 14 precipitation, and 3 wet days series), mainly in northern Europe (before ca. 1750) and in Russia,
were calculated following the Julian calendar (i.e., 10-12 days behind Gregorian, depending on the century). 
There are two possible scenarios when the Julian calendar is adopted:
- the source provided the monthly means/totals after the Julian calendar with no corrections (metadata entry: 'Calendar=Julian');
- the source interpolated the Julian monthly means to the Gregorian calendar (metadata entry: 'Calendar=Interpolated').
Different interpolations are used. For example 'Calendar=Interpolated (1/3 + 2/3)' indicates that the monthly mean X of the month i was calculated as:
X(i) = [J(i-1) + 2*J(i)] / 3
where J indicates the original monthly means after the Julian calendar.

MID-RANGE AVERAGES
17 monthly mean series (15 pressure, 2 temperature series), all from the 18th century, were calculated from the average of the monthly minimum and maximum values.
For these series the statistic 'mid_range' is used in the SEF header instead of 'mean'.

COLUMN METADATA
The following metadata are included in the column Meta of the SEF files:
- original value as keyed (with original units, see below)
- original date (if different from UTC date)
- original observation time (if available)
- quality control flags (label 'qc=', as generated by R package dataresqc v1.1: https://cran.r-project.org/package=dataresqc)
- attached temperature of the barometer in the original units (for pressure only, if available)

ABBREVIATIONS
Parameter abbreviations follow the Copernicus Climate Service (C3S) guidelines (https://datarescue.climate.copernicus.eu). The most important are:
p = surface pressure
ta = air temperature
Tx = daily maximum air temperature
Tn = daily minimum air temperature
rr = precipitation amount
nr = number of wet days
rrt = precipitation type
dd = wind direction
w = wind force
rh = relative humidity
tb = wet bulb temperature
sd = snow depth

The following abbreviations are used for original non-metric units:
in = British inch (25.4 mm)
Pin = Paris inch (27.07 mm)
Pl = Paris line (2.256 mm)
Rh.in/Rin/Din = Rijnland/Danish inch (26.154 mm)
Swed.in = Swedish inch (29.69 mm)
Br.in = Breslau inch (23.996 mm)
F = Fahrenheit
R = Réaumur
DC = Micheli du Crest
De = Delisle
H = Royal Society's (Hauksbee) thermometer


Note that some series (mainly temperature and humidity) are non available in SEF because of insufficient information available on the instrument/scale (see inventory).


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Note on coordinates
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Geographical coordinates refer in general to an approximate position that can differ by up to a few tens of kilometers from the actual station location.
Elevation, when available, was usually obtained from the data source (i.e., its accuracy is at best equal to that achievable at the time of the measurements).


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Note on data sources
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The data were keyed from a large number of heterogeneous sources: manuscripts, periodical, books... Details on most of the sources can be found in the Supplementary Materials of:
Brönnimann, S., et al. (2019). Unlocking Pre-1850 Instrumental Meteorological Records: A Global Inventory, Bulletin of the American Meteorological Society, 100(12), ES389-ES413.
https://doi.org/10.1175/BAMS-D-19-0040.1