It's a lightly processed version of the daily and monthly summaries climate dataset released by the Spanish metoffice (AEMET) during 2011 and up until November 2012. It includes basic weather observations like precipitation and temperature for 114 Spanish weather stations for the period between 1920 and 2012, in a format that makes it easier to use for data analysis.
This dataset was available free of charge during 2011 and most of 2012 but due to a change in government policy it's now only accessible for a fee, see [here] (https://sede.aemet.gob.es/AEMET/en/GestionPeticiones/solicitudes) for how to access an updated version of these data, subject to charge.
The original raw data this dataset is derived from is available here. Its a copy hosted by a trusted member of the Spanish stormchaser community. I can't 100% guarantee its integrity or provenance, however myself and others who have made use of it have found no issues so far.
I've also included the python scripts I used to process the original data into standard format csv files, as well as scripts to load these csv files into Sqlite.
Here's a field by field description of the changes I made:
stations.csv (description of each weather station):
- indisinop: id, removed as redundant
- lat,long: converted from degrees, minutes, seconds to decimal degrees
- place: replaced commas with colons and removed inverted commas
- region: added Spanish region each stations is in
spanish_daily.csv:
- place, province, altitude: removed, redundant as present in stations file
- average temperature: removed , redundant as derived from min and max
- times of max and min temperature and pressure and gust speed: removed as too detail for most analyses
- precipitation: replaced the string 'trace' with .05, half way between 0 and .1, the minimum quantity non-zero recorded, also replaced string 'Acum' with empty, unsure what this is meant to be ( presumably 'Accumulated')
- direction of strongest gust: converted from tens of degree to degrees, also there were some fields with values 99 and 88, outside the allowed range 0-36, that appear to mark days where gust direction was variable
- highest gust speed, average wind speed: converted from m/s to km/hr
spanish_monthly.csv:
- place, province, altitude: same as above
- times of max and min temperature, pressure, precipitation, highest wind speed : removed as too detail for most analyses
- direction of strongest gust: same as above
- highest gust speed, average wind speed: same as above
wind_directions.csv :
- added csv file (and corresponding db table) to map wind direction degrees to compass directions, for convenience
all:
- converted to utf-8 from the original latin-1 encoding
- replaced continental decimal point , to .
- replaced field separator ; with ,
- translated original Spanish to English
units:
- temperature: degrees Celsius
- precipitation: millimeters/liters per square metre
- pressure: millibars/hectopascals
- wind speed: kilometres per hour
- lat,long: decimal degrees
- wind direction: degrees from north (clockwise)
The code is MIT-licensed. The license for the original data was none of the well known ones but my reading of it is that it was essentially a permissive MIT-style one. My translation of the Spanish original:
The collection and processing of meteorological information, the result of
scientific and technical work by the State Meteorological Agency
(AEMET), in line with scientific and technological progress,
are a form of intellectual property governed by Article
10 of Royal Legislative Decree 1/1996 of 12 April (Intellectual Property Law).
AEMET retains ownership and exercise of all rights,
both moral and economic, which form the exclusive right to
the exploitation and dissemination of such information.
The information obtained and processed by AEMET is created with the highest
reliability afforded by current technology. This service is provided
with the means available at the time.
The information on this server is provided free to
citizens so that it can be freely used by them, with the sole
commitment to explicitly mention AEMET as processors of it
each time it is used for purposes other than individual and private ones.
AEMET declines all responsibility for damages that may
be incurred by the interpretation and use of the information made
available to the public on this server.
AEMET does not guarantee the full presentation of data on a continuous basis
on the server, also it reserves the right to modify, add or delete information
contained thereon.