Rainfall estimates (CHIRPS)

Date modified: 12 January 2022

Aperçu du produit

Contexte

Digital Earth Africa (DE Africa) provides free and open access to a copy of the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) monthly and daily products over Africa. The CHIRPS rainfall maps are produced and provided by the Climate Hazards Center in collaboration with the US Geological Survey, and use both rain gauge and satellite observations.

The CHIRPS-2.0 Africa Monthly dataset is regularly indexed to DE Africa from the CHIRPS monthly data. The CHIRPS-2.0 Africa Daily dataset is likewise indexed from the CHIRPS daily data. Both products have been converted to cloud-opitmized GeoTIFFs, and can be accessed through DE Africa’s Open Data Cube. This means the full archive of CHIRPS daily and monthly rainfall can be easily used for inspection or analysis across DE Africa platforms, including the user-interactive DE Africa Map.

A Jupyter Notebook which demonstrates loading and using CHIRPS datasets in the Sandbox is also available.

This page details how to access CHIRPS products through DE Africa platforms. For more information on the dataset, see the official CHIRPS website:

« Estimating rainfall variations in space and time is a key aspect of drought early warning and environmental monitoring. An evolving drier-than-normal season must be placed in a historical context so that the severity of rainfall deficits can be quickly evaluated. However, estimates derived from satellite data provide areal averages that suffer from biases due to complex terrain, which often underestimate the intensity of extreme precipitation events. Conversely, precipitation grids produced from station data suffer in more rural regions where there are less rain-gauge stations. CHIRPS was created in collaboration with scientists at the USGS Earth Resources Observation and Science (EROS) Center in order to deliver complete, reliable, up-to-date data sets for a number of early warning objectives, like trend analysis and seasonal drought monitoring. »

Spécifications

Couverture spatiale et temporelle

DE Africa provides the monthly and daily CHIRPS datasets as two seperate products.

Table 1: Rainfall CHIRPS products” specifications

Specification

Nom du produit

Rainfall - CHIRPS daily

Rainfall - CHIRPS monthly

Cell size - X (degrees)

0.05 (~5 km)

0.05 (~5 km)

Cell size - Y (degrees)

0.05 (~5 km)

0.05 (~5 km)

Système de référence des coordonnées

EPSG : 4326

EPSG : 4326

Résolution temporelle

1 day

1 month

Plage temporelle

1981 – present

1981 – present

Fréquence de mise à jour

Quotidiennement

Monthly

Table 2: Rainfall CHIRPS products” measurements

Nom du produit

ID de la bande

Description

Unités

Type de données

Aucune valeur de données

Rainfall - CHIRPS daily

rainfall

Monthly Atmospheric Precipitation

mm

float32

-9999.0

Rainfall - CHIRPS monthly

rainfall

Daily Atmospheric Precipitation

mm

float32

-9999.0

Both rainfall CHIRPS products have the same geographic extent. Data is available for the region shaded in Figure 1.

Specific temporal and geographic extents can be explored as an interactive map on the Digital Earth Africa Metadata Explorer:

Figure 1: CHIRPS products” geographic extent

Rainfall CHIRPS Geographic Extent

Traitement

The Climate Hazards group Infrared Precipitation with Stations (CHIRPS) algorithm was developed by the Climate Hazards Center and is described in Funk, C., Peterson, P., Landsfeld, M. et al. (2015).

Médias et exemples d’images

Image 1: Animation of monthly Rainfall CHIRPS over Nigeria from 2020 to 2021.

Rainfall over Nigeria

Credit: Contains Rainfall CHIRPS Product courtesy of the Climate Hazards Center, processed by Digital Earth Africa.

Image 2: Mean monthly rainfall for 2020, calculated using monthly CHIRPS rainfall.

Mean monthly rainfall per country

Credit: Contains Rainfall CHIRPS Product courtesy of the Climate Hazards Center, processed by Digital Earth Africa.

Références

Funk, C., Peterson, P., Landsfeld, M. et al. (2015). The climate hazards infrared precipitation with stations—a new environmental record for monitoring extremes. Sci Data 2, 150066. https://doi.org/10.1038/sdata.2015.66

CHIRPS website

Licence

CHIRPS data is in the public domain as registered with Creative Commons. From the CHIRPS website:

To the extent possible under the law, Pete Peterson has waived all copyright and related or neighboring rights to Climate Hazards Group Infrared Precipitation with Stations (CHIRPS).

Remerciements

The CHIRPS monthly and daily products are provided by the Climate Hazards Center (CHC), UC Santa Barbara.

Accès aux données

Amazon Web Service S3

The Digital Earth Africa CHIRPS products are available in AWS S3.

Tableau 3 : Détails de l’accès aux données AWS.

Détails sur AWS S3

Seau ARN

arn:aws:s3:::deafrica-input-datasets

Région

af-south-1

Nom du produit

rainfall_chirps_monthly, rainfall_chirps_daily

Le seau se trouve dans la région AWS af-south-1 (Cape Town). Des spécifications de région supplémentaires peuvent être appliquées comme suit :

aws s3 ls --region=af-south-1 s3://deafrica-input-datasets/

The following file path conventions apply to the rainfall_chirps_monthly and rainfall_chirps_daily products respectively:

s3://deafrica-input-datasets/rainfall_chirps_monthly/

s3://deafrica-input-datasets/rainfall_chirps_daily/<year>/<month>/

Services Web de l’OGC (OWS)

The CHIRPS product rainfall_chirps_monthly is available through Digital Earth Africa’s OWS.

Table 4: OWS data access details

Détails de l’OWS

Nom

DE Africa Services

URL des services cartographiques Web (WMS)

https://ows.digitalearth.africa/wms?version=1.3.0

URL du service de couverture Web (WCS)

https://ows.digitalearth.africa/wcs?version=2.1.0

Nom de la couche

rainfall_chirps_monthly

Les détails de Digital Earth Africa OWS peuvent être trouvés sur https://ows.digitalearth.africa/.

Pour obtenir des instructions sur la manière de se connecter à OWS, consultez ce tutoriel.

Open Data Cube (ODC)

CHIRPS products can be accessed through the Digital Earth Africa ODC API, which is available through the Digital Earth Africa Sandbox.

ODC product names: rainfall_chirps_monthly, rainfall_chirps_daily

The rainfall_chirps_monthly and rainfall_chirps_daily products have only one band of data, rainfall, which can be called by using the band name as listed in the table below. ODC Datacube.load commands without specified measurements will also load the rainfall band.

Table 5: Rainfall - CHIRPS ODC products and band names

Nom du produit

Nom du groupe

Noms alternatifs

rainfall_chirps_monthly

rainfall

rainfall_chirps_daily

rainfall

Les noms de produits et de groupes sont sensibles à la casse.

Instructions on how to access and use CHIRPS products from the DE Africa Open Data Cube are provided in the Rainfall CHIRPS dataset example notebook.

Technical Information

Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) is a 35+ year quasi-global rainfall data set, spanning 50°S-50°N (and all longitudes) and ranging from 1981 to near-present. CHIRPS incorporates the Climate Hazards group Precipitation climatology (CHPclim) that incorporates satellite information to represent sparsely gauged locations, 0.05° resolution satellite-only CCD-based Climate Hazards group Infrared Precipitation (CHIRP) estimates, and in-situ station data to create gridded rainfall time series for trend analysis and seasonal drought monitoring.

For more information on the algorithm used to generate the CHIRPS datasets visit the CHIRPS pulication.