Variables
Historical Archive 2021
Historical Archive 2020
Historical Archive 2018
Climate indices
Percentiles
Return levels
Notes
Operational updates version 21.09(21.10) (historical archive available on Zenodo, click on the DOIs)
| VAR | nc | description | Time period | DOI | daily updates | unit |
|---|---|---|---|---|---|---|
| TG | tg | Mean temperature (yesterday at 06 UTC / today at 06 UTC) | 1957-2020 |  |
2021-01-01, today | Celsius degrees |
| TM | tm | Mean temperature (today at 00 UTC / today at 24 UTC) | 1957-2020 |  |
none | Celsius degrees |
| TX | tx | Maximum temperature consistent with TG/TN (yesterday at 18 UTC / today at 18 UTC) | 1957-2020 |  |
2021-01-01, today | Celsius degrees |
| TXa | txa | Maximum temperature without checking for consistency with TG/TM/TN | 1957-2020 |  |
none | Celsius degrees |
| TXb | txb | Maximum temperature consistent with TM/TN | 1957-2020 |  |
none | Celsius degrees |
| TN | tn | Minimum temperature consistent with TG/TX (yesterday at 18 UTC / today at 18 UTC) | 1957-2020 |  |
2021-01-01, today | Celsius degrees |
| TNa | tna | Minimum temperature without checking for consistency with TG/TM/TX | 1957-2020 |  |
none | Celsius degrees |
| TNb | tnb | Minimum temperature consistent with TM/TX | 1957-2020 |  |
none | Celsius degrees |
| RR | rr | Daily total of precipitation (precipitation day definition: yesterday at 06 UTC / today at 06 UTC) | 1957-2020 |  |
2021-01-01, today | mm/day |
| RRa | rra | Daily total of precipitation without adjustment for the wind undercatch | 1957-2020 | |
none | mm/day |
Archive version 20.05 (available on Zenodo, click on the DOIs)
| VAR | nc | description | Time period | DOI | daily updates | unit |
|---|---|---|---|---|---|---|
| TG | tg | Mean temperature (yesterday at 06 UTC / today at 06 UTC) | 1957-2019 |  |
none | Celsius degrees |
| TX | tx | Maximum temperature (yesterday at 18 UTC / today at 18 UTC) | 1957-2019 |  |
none | Celsius degrees |
| TX alt | txa | Maximum temperature without checking for consistency with TG/TN | 1957-2019 | |
none | Celsius degrees |
| TN | tn | Minimum temperature (yesterday at 18 UTC / today at 18 UTC) | 1957-2019 |  |
none | Celsius degrees |
| TN alt | tna | Minimum temperature without checking for consistency with TG/TX | 1957-2019 | |
none | Celsius degrees |
| RR | rr | Daily total of precipitation (precipitation day definition: yesterday at 06 UTC / today at 06 UTC) | 1957-2019 |  |
none | mm/day |
| RR alt | rra | Daily total of precipitation without adjustment for the wind undercatch | 1957-2019 | |
none | mm/day |
Archive version 18.12 (available on Zenodo, click on the DOIs)
| VAR | nc | description | Time period | DOI | daily updates | unit |
|---|---|---|---|---|---|---|
| TG | tg | Mean temperature (yesterday at 06 UTC / today at 06 UTC) | 1957-2017 |  |
none | Celsius degrees |
| TX | tx | Maximum temperature (yesterday at 18 UTC / today at 18 UTC) | 1957-2017 |  |
none | Celsius degrees |
| TN | tn | Minimum temperature (yesterday at 18 UTC / today at 18 UTC) | 1957-2017 |  |
none | Celsius degrees |
| RR | rr | Daily total of precipitation (precipitation day definition: yesterday at 06 UTC / today at 06 UTC) | 1957-2017 |  |
none | mm/day |
Climate Change Indices. The definitions of the core indices can be found at ETCCDI web page.
THIS IS AN EXPERIMENTAL PRODUCT, it can change at any time without notice (Cristian Lussana, 2022-06-07).
Percentile classes for daily aggregated values. Based on the reference time period 1991-2020 and version 21.09. Summary of the calculation procedure for today's percentile class of one daily variable (RR, TG, TX or TN)
- First step, Calculation of the percentiles. We consider the 30-year time period from 1991-2020. Then, we consider a time window of 30 days centered on the same date as today's date over the 30-year reference period. We have a total of: 30 days x 30 years = 900 days (or 900 gridded fields) as the database for the calculation of percentiles. The percentiles are computed gridpoint-by-gridpoint on this database of gridded fields. Precipitation is considered only when the daily amount is higher than 1 mm and, as a consequence, the number of samples is usually less than 900 predictions. We will refer to these percentiles as gridpoint-percentiles in the following. Note that in order to optimize the computational time, the reference percentiles were prepared in advance but not for all days. For each month, we have used the days: 01 (1st), 05 (5th), 10, 15, 20, 25, 28; then, we use the day of the month closest to today.
- Second step, Regionalization. The percentiles obtained from seNorge_2018 for daily variables are more significant in climatic terms if aggregated over regions rather than presented as gridpoint-by-gridpoint comparisons. For this reasons, the percentile classes for temperature TGQ, TXQ and TNQ at each gridpoint represent the average of the gridpoint-percentiles in a squared neighborhood of 51 x 51 gridpoints centered on that gridpoint (i.e. corresponding to 50 x 50 km²). The regionalization for precipitation is different, because: i) the expected distribution of daily values is different between precipitation and temperatures, especially for the "ticker" tail of precipitation ii) we have less samples for precipitation than for temperature. For each gridpoint: we consider 100 random cells in a squared neighborhood of 51 x 51 gridpoints centered on that gridpoint (i.e. 50 x 50 km²); we compare today's precipitation value with the percentiles of the 100 cells, we have 100 possible percentile classes and we temporarily assign the lower class to that point; RRQ is the average of the provisional percentile classes in a squared neighborhood of 25 x 25 gridpoints centered on that gridpoint.
In conclusion, the variables RRQ, TGQ, TXQ, TNQ would like to define percentile classes for fairly extensive events, i.e. approximately 50 x 50 km², and we would like to try to avoid that the observations measured by one or a few stations (which may not be present in the reference period) decisively determine the percentile class in one point.
| VAR | nc | description | Reference time period | DOI | daily updates | unit |
|---|---|---|---|---|---|---|
| RRQ | rrq | daily total precipitation percentile class. Classes are: 1 = smaller than 75%, 2 = between 75% and 90%, 3 = between 90% and 95%, 4 = between 95% and 99%, 5 = greater than 99% | 1991-2020 | - | 2022-04-01, today | 1 |
| TGQ | tgq | mean daily air temperature percentile class. Classes are: 1 = smaller than 1%, 2 = between 5% and 10%, 3 = between 10% and 25%, 4 = between 25% and 50%, 5 = between 50% and 75%, 6 = between 75% and 90%, 7 = between 95% and 99%, 8 = greater than 99% | 1991-2020 | - | 2022-04-01, today | 1 |
| TXQ | txq | maximum daily air temperature percentile class. Classes are: 1 = smaller than 1%, 2 = between 5% and 10%, 3 = between 10% and 25%, 4 = between 25% and 50%, 5 = between 50% and 75%, 6 = between 75% and 90%, 7 = between 95% and 99%, 8 = greater than 99% | 1991-2020 | - | 2022-04-01, today | 1 |
| TNQ | tnq | minimum daily air temperature percentile class. Classes are: 1 = smaller than 1%, 2 = between 5% and 10%, 3 = between 10% and 25%, 4 = between 25% and 50%, 5 = between 50% and 75%, 6 = between 75% and 90%, 7 = between 95% and 99%, 8 = greater than 99% | 1991-2020 | - | 2022-04-01, today | 1 |
THIS IS AN EXPERIMENTAL PRODUCT, it can change at any time without notice (Cristian Lussana, 2022-06-07).
Return levels for daily precipitation totals based on version 20.05.
| VAR | nc | description | Reference time period | file | daily updates | unit |
|---|---|---|---|---|---|---|
| M5rr1d | M5 | 5-year return level | 1991-2020 | M5rr1d-nc | - | mm |
| M10rr1d | M10 | 10-year return level | 1991-2020 | M10rr1d-nc | - | mm |
| M50rr1d | M50 | 50-year return level | 1991-2020 | M50rr1d-nc | - | mm |
- "nc" is the abbreviation used in the netcdf files
- The observations undergo an automatic quality control procedure TITAN.
- The precipitation observations are adjusted for the wind-induced undercatch, unless otherwise specified.