SPEIbase: Standardised Precipitation-Evapotranspiration Index database, Version 2.9

CSIC/SPEI/2_9
Dataset Availability
1901-01-01T00:00:00Z–2023-01-01T00:00:00Z
Dataset Provider
Earth Engine Snippet
ee.ImageCollection("CSIC/SPEI/2_9")

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

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');
Open in Code Editor
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), …
CSIC/SPEI/2_9, climate,climate-change,drought,evapotranspiration,global,monthly,palmer,precipitation,temperature
1901-01-01T00:00:00Z/2023-01-01T00:00:00Z
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