- Dataset Availability
- 1901-01-01T00:00:00Z–2023-01-01T00:00:00Z
- Dataset Provider
- Spanish National Research Council (CSIC)
- Earth Engine Snippet
-
ee.ImageCollection("CSIC/SPEI/2_9")
- Tags
Description
The Global SPEI database (SPEIbase) offers long-time robust information about drought conditions at the global scale, with a 0.5 degree pixel size and monthly cadence. It provides SPEI time scales from 1 to 48 months.
The Standardized Precipitatin-Evapotranspiration Index (SPEI) expresses, as a standardized variate (mean zero and unit variance), the deviations of the current climatic balance (precipitation minus evapotranspiration potential) with respect to the long-term balance. The reference period for the calculation in the SPEIbase corresponds to the whole study period. Being a standardized variate means that the SPEI condition can be compared across space and time.
The SPEIbase is based on the FAO-56 Penman-Monteith estimation estimation of potential evapotranspiration. This is a major difference with respect to the SPEI Global Drought Monitor, that uses the Thornthwaite PET estimation. The Penman-Montheith method is considered a superior method, so the SPEIbase is recommended for most uses including long-term climatological analysis.
Bands
Resolution
55660 meters
Bands
Name | Min | Max | Description |
---|---|---|---|
SPEI_01_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous month |
SPEI_02_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 2 months |
SPEI_03_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 3 months |
SPEI_04_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 4 months |
SPEI_05_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 5 months |
SPEI_06_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 6 months |
SPEI_07_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 7 months |
SPEI_08_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 8 months |
SPEI_09_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 9 months |
SPEI_10_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 10 months |
SPEI_11_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 11 months |
SPEI_12_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 12 months |
SPEI_13_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 13 months |
SPEI_14_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 14 months |
SPEI_15_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 15 months |
SPEI_16_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 16 months |
SPEI_17_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 17 months |
SPEI_18_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 18 months |
SPEI_19_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 19 months |
SPEI_20_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 20 months |
SPEI_21_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 21 months |
SPEI_22_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 22 months |
SPEI_23_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 23 months |
SPEI_24_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 24 months |
SPEI_25_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 25 months |
SPEI_26_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 26 months |
SPEI_27_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 27 months |
SPEI_28_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 28 months |
SPEI_29_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 29 months |
SPEI_30_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 30 months |
SPEI_31_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 31 months |
SPEI_32_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 32 months |
SPEI_33_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 33 months |
SPEI_34_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 34 months |
SPEI_35_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 35 months |
SPEI_36_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 36 months |
SPEI_37_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 37 months |
SPEI_38_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 38 months |
SPEI_39_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 39 months |
SPEI_40_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 40 months |
SPEI_41_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 41 months |
SPEI_42_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 42 months |
SPEI_43_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 43 months |
SPEI_44_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 44 months |
SPEI_45_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 45 months |
SPEI_46_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 46 months |
SPEI_47_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 47 months |
SPEI_48_month |
-2.33 | 2.33 | Standardized Precipitation-Evapotranspiration Index (SPEI) where precipitation and evapotranspiration data was accumulated over the previous 48 months |
Terms of Use
Terms of Use
The SPEI database is available under the CC-BY 4.0 license.
Any public use of the database or works derived from it must include proper attribution. Attribution should be given by referencing the document titled: Beguería, Santiago; Vicente Serrano, Sergio M.; Reig-Gracia, Fergus; Latorre Garcés, Borja; 2023; SPEIbase v.2.9 [Dataset]; DIGITAL.CSIC; Version 2.9. doi:10.20350/digitalCSIC/15470
Citations
Reig-Gracia, Fergus; Latorre Garcés, Borja; 2023; SPEIbase v.2.9 [Dataset]; DIGITAL.CSIC; Version 2.9. doi:10.20350/digitalCSIC/15470
Related publication: Vicente-Serrano S.M., Beguería S., López-Moreno J.I. (2010): A Multi-scalar drought index sensitive to global warming: The Standardized Precipitation Evapotranspiration Index - SPEI. Journal of Climate 23(7), 1696-1718. doi:10.1175/2009JCLI2909.1
DOIs
Explore with Earth Engine
Code Editor (JavaScript)
// Retrieve the last date from the SPEI dataset. var dataset = ee.ImageCollection("CSIC/SPEI/2_9"). filterDate('2022-12-01', '2023-01-01'); // Select the 24-month analysis. var spei24 = dataset.select('SPEI_24_month'); // Set the visualization ranges and color palette. var visParams = { min: -2.33, max: 2.33, palette: [ '8b1a1a', 'de2929', 'f3641d', 'fdc404', '9afa94', '03f2fd', '12adf3', '1771de', '00008b', ] }; // Set the map center to Spain's location. Map.setCenter(-3.75, 40.47, 4); // Display the SPEI 24-month layer. Map.addLayer(spei24, visParams, 'SPEI 24 month');