This page lists notable changes to the service. If the service behaves in new or unexpected ways, the changelog might give a hint as to what has recently been changed in the code base.

DateDescription of change
2021-06-01 Some of the time series have had misleading and wrong element IDs and are moved from these old element IDs to new element IDs:

Old element IDNew element ID
2021-06-01 Removal of period from the element ID of some time series, where period varies as time since last main observation time: 00, 06, 12, and 18 UTC.

Some of the time series that used to have one of the following element IDs:
  • max(wind_speed PT10M)
  • max(wind_speed PT6H)
  • max(wind_speed PT3H)
will have their element ID renamed to just max(wind_speed).
2021-04-19 Updated element IDs:

Old element IDNew element IDOld convention element code
min(sea_surface_wind_wave_mean_period P1D)min(sea_surface_wave_mean_period P1D) PWAN_d
max(sea_surface_wind_wave_mean_period P1D)max(sea_surface_wave_mean_period P1D)PWAX_d
mean(sea_surface_wind_wave_mean_period P1D)mean(sea_surface_wave_mean_period P1D)PWAM_d
min(sea_surface_wind_wave_mean_height P1D)min(sea_surface_wave_significant_height P1D)HWAN_d
max(sea_surface_wind_wave_mean_height P1D)max(sea_surface_wave_significant_height P1D)HWAX_d
mean(sea_surface_wind_wave_mean_height P1D)mean(sea_surface_wave_significant_height P1D)HWAM_d
min(sea_surface_wind_wave_mean_period P1M)min(sea_surface_wave_mean_period P1M)PWAN_m
max(sea_surface_wind_wave_mean_period P1M)max(sea_surface_wave_mean_period P1M)PWAX_m
mean(sea_surface_wind_wave_mean_period P1M)mean(sea_surface_wave_mean_period P1M)PWAM_m
min(sea_surface_wind_wave_mean_height P1D)min(sea_surface_wave_significant_height P1D)HWAN_m
max(sea_surface_wind_wave_mean_height P1D)max(sea_surface_wave_significant_height P1D)HWAX_m
mean(sea_surface_wind_wave_mean_height P1D)mean(sea_surface_wave_significant_height P1D)HWAM_m
2019-09-23 Bug fix: When specifying referencetime=latest in the observations endpoint, the limit parameter now applies to reference times, not observations. When specifying for example limit=2, the output now contains all observations at the two most recent observation times for any given source/element combination. Note in particular that the output may contain more than one observation even when specifying limit=1. Observations for the same time will differ in some other meta attribute than source or element, like sensor level or time resolution.
2019-07-10 A new filtering feature has been made for the observations and availableTimeSeries endpoints. It is now possible to specify levels=default and timeoffsets=default. See the concepts page for more information.
2019-07-01 The exposure and perfomance category values are now being inserted from the metadata database, and should more correctly represent the stations that are less trustworthy.
2019-06-17 In the sources/ endpoint, the query parameter elements has been added as an additional filter. If specified, only station (sensor system) sources matching these elements may appear in the output.
2019-04-14 The value of the max-age header in the response from the observations endpoint now shows the actual remaining period (in seconds) during which Frost will reply with the same response to this request. There is no point in resending the request during this period and the traffic can be saved.
  • Note: New observations relevant to the response may or may not arrive in backend database during the max-age period.
  • A max-age value of -1 means that the value is undefined or n/a, for example if the response is not cached internally at all by Frost.
2019-02-20 The maximum total number of observations that can be asked for in one request has been lowered to 100,000.
2019-02-08 In the sources/ endpoint, the query parameter externalid has been renamed to externalids and allows a comma-separated list of values.
2019-01-25 The term CF status has been renamed to CF version to reflect precisely what this attribute represents. Usually it will be an integer value, such as 44.
2018-11-29 When using repeating intervals for the time specification, a check is now made to ensure that the number of intervals is at least 2. Note: R1/from/to and R1/from/to/duration are both equivalent to just from/to.
2018-11-05 There is a new filter field in the observations/ endpoint, which allows you to request only certain qualities of data. For example you can request only the best qualities 0 and 1 by writing 0,1 in the qualites field. If you do not write anything in the field you will get all the qualities of data. Please be aware that some types of data (such as averages over time) do not have qualities, and so if you try to filter on quality you will get no data returned. You can read more about about what the quality codes mean in availableQualityCodes/.
2018-08-28 When using the nearest() function for geometry in the sources/ endpoint, an arbitrary number of sources (limited by nearestmaxcount) may now be returned. Distances from the reference point are included in the output. Note that the geometry feature currently applies to point sources only (i.e. weather stations, prefixed with 'SN').
2018-07-23 The request for observations now return status code 503 (Service unavailable) when there are to many requests in progress. Retry-After is set to the number of seconds to wait before retrying the request.
2018-06-25 As part of improving the overall resource allocation in Frost, a request for observations will be rejected if the response may result in more than 1000000 individual values. Moreover, it will not be possible to specify more than 1000 interval repetitions for the referencetime (e.g. R1001/2018-.../2018-... will be rejected). A request that exceeds any of these limits will be rejected with 403 Forbidden.
2018-04-30 When specifying referencetime=latest in a request for observations, the Cache-Control/max-age in the HTTP response header is set to the minimum value of the normal update periods of any of the following elements occurring in the request:
  • air_temperature (3600)
  • wind_speed (600)
  • wind_from_direction (600)
If none of these elements are requested, the default value is 3600.
2018-04-26 Added maxage and limit to reduce response time when specifying referencetime=latest in a request for observations.
  • maxage: don't retrieve observations older than this duration
  • limit: return values for at most limit observation times for each source/element combination, counting from the most recent time
2018-03-22 Updated IDs of elements and code tables:

Old element IDNew element IDOld convention element code
over_time(precipitation_type_primary_significance PT6H)over_time(weather_class1_primary_significance PT6H)V4
over_time(precipitation_type_primary_significance_intensity P1D)over_time(weather_class1_primary_significance_intensity PT6H)V4S
over_time(precipitation_type_secondary_significance P1D)over_time(weather_class1_secondary_significance PT6H)V5
over_time(precipitation_type_secondary_significance PT6H)over_time(weather_class1_secondary_significance PT6H)V5
over_time(precipitation_type_secondary_significance_intensity P1D)over_time(weather_class1_secondary_significance_intensity PT6H)V5S
over_time(precipitation_type_tertiary_significance PT6H)over_time(weather_class1_tertiary_significance PT6H)V6
over_time(precipitation_type_tertiary_significance P1D)over_time(weather_class1_tertiary_significance PT6H)V6
over_time(precipitation_type_tertiary_significance_intensity P1D)over_time(weather_class1_tertiary_significance_intensity PT6H)V6S
over_time(precipitation_type_quaternary_significance PT6H)over_time(weather_class1_quaternary_significance PT6H)V7

Old code table IDNew code table ID
2018-03-19 Removed leading zeros from a couple of time offset values:
  • PT00HPT0H
  • PT06HPT6H
2018-03-17 Updated element IDs that previously matched one the following patterns:
  • *sea_surface*
  • *precipitation_type*
  • humidity_mixing_ratio
  • In the observations/ endpoint, the referencetime parameter now accepts the word 'latest' to specify the latest available observation.
  • If 'latest' is specified for referencetime, the response header for now contains max-age=3600 as the value of Cache-Control. This will be fine for most elements. At a later point, the value of max-age may depend on the element in the request that is expected to be updated most frequently.
2018-03-06 Starting point.