Data
Index datasets
A catalogue of the climate hazard index datasets earthflux produces, and plans to produce, from public data sources. Each entry lists its inputs and the sources it can be generated from; live previews show real calculated values for the products published so far.
PreviewPreviews cover SPI and SPEI only, calculated from NOAA nClimGrid on a sampled grid (about 0.33°), not the full-resolution product. Everything else in the catalogue is planned. Full-grid Zarr and NetCDF downloads are not published; the addresses below are examples, not live links.
Dataset catalogue
2 live previews41 planned datasetsPreview: values are browsable below. Planned: on the roadmap, not yet published.
Drought
| Index | Inputs | Datasets by source |
|---|---|---|
| Standardized Precipitation IndexSPI | Precipitation |
|
| Standardized Precipitation Evapotranspiration IndexSPEI | Precipitation, PET |
|
| Self-calibrated Palmer Drought Severity IndexscPDSI | Precipitation, PET, available water capacity |
|
| Palmer Drought Severity Index familyPDSI, PHDI, PMDI, Z-Index | Precipitation, PET, available water capacity |
|
| Evaporative Demand Drought IndexEDDI | Reference evapotranspiration |
|
| Potential evapotranspiration, ThornthwaitePET | Mean temperature, latitude |
|
| Potential evapotranspiration, HargreavesPET | Min and max temperature, latitude |
|
| Reference evapotranspiration, Penman–MonteithETo | Temperature, humidity, radiation, wind |
|
| Percentage of normal precipitationPNP | Precipitation |
|
| Precipitation Concentration IndexPCI | Daily precipitation |
|
Fire
| Index | Inputs | Datasets by source |
|---|---|---|
| Keetch–Byram Drought IndexKBDI | Daily max temperature, daily precipitation, mean annual precipitation |
|
| Canadian Forest Fire Weather Index SystemFFMC, DMC, DC, ISI, BUI, FWI, DSR | Noon temperature, relative humidity, wind, 24-hour precipitation |
|
| Fosberg Fire Weather IndexFFWI | Temperature, relative humidity, wind |
|
| Hot-Dry-Windy IndexHDW | Temperature, humidity and wind on pressure levels |
|
| Haines IndexHaines | Temperature and dew point at two pressure levels |
|
Flood
| Index | Inputs | Datasets by source |
|---|---|---|
| Effective precipitationPE | Daily precipitation |
|
| Effective Drought IndexEDI | Daily precipitation |
|
| Flood IndexI_F | Daily precipitation |
|
| Antecedent Precipitation IndexAPI | Daily precipitation |
|
Energy
| Index | Inputs | Datasets by source |
|---|---|---|
| Heating, cooling and energy degree daysHDD, CDD, EDD | Daily mean temperature, heating and cooling base temperatures |
|
| Hub-height wind speedWind profile | Wind speed, reference and hub heights, shear method |
|
| Wind capacity factorWind CF | Hub-height wind speed, power curve, air density |
|
| PV capacity factor, temperature-deratedPV CF | Surface solar radiation as a mean flux (W m⁻²), 2 m temperature, 10 m wind |
|
| Standardized Renewable Energy Production IndexSREPI | Renewable production proxy or capacity factor, timescales, calibration years |
|
| Standardized demand indexDemand index | Energy demand proxy, timescales, calibration years |
|
| Standardized Residual Load IndexSRLI | Residual-load proxy (signed), timescales, calibration years |
|
Preview viewer
Real SPI and SPEI values calculated from NOAA nClimGrid inputs, sampled at every 8th source grid cell for fast browsing. Gamma-distribution maps and location histories cover 1, 2, 3, 6, 9, 12, 24 and 36 months through August 2026. Other indices appear here as their datasets are published.
SPI-12, gamma
Loading
Loading index data
- Extremely dry≤ −2.0
- Severely dry−2.0 to −1.5
- Moderately dry−1.5 to −1.0
- Near normal−1.0 to 1.0
- Moderately wet1.0 to 1.5
- Very wet1.5 to 2.0
- Extremely wet≥ 2.0
Planned files for SPI-12, gamma, nClimGrid monthly
Each product is planned as a Zarr store for partial reads over HTTPS and a single NetCDF file. The intended coverage is the full 1/24° grid from January 1895.
https://data.earthflux.org/nclimgrid/monthly/nclimgrid_spi_gamma_12.zarrhttps://data.earthflux.org/nclimgrid/monthly/nclimgrid_spi_gamma_12.ncExample paths and commands only. Do not use these addresses until the first products are published.
# Read only the cells and months you need (no account or key required)
import xarray as xr
ds = xr.open_zarr(
"https://data.earthflux.org/nclimgrid/monthly/nclimgrid_spi_gamma_12.zarr",
)
oklahoma_city = ds["spi_gamma_12"].sel(lat=35.47, lon=-97.52, method="nearest")
august_2011 = ds["spi_gamma_12"].sel(time="2011-08")
# Or copy the whole NetCDF file
curl -O https://data.earthflux.org/nclimgrid/monthly/nclimgrid_spi_gamma_12.nc
Input sources
nClimGrid monthly
NOAA NCEI
Contiguous US, about 5 km, 1895 to present. Precipitation, mean, min and max temperature. 596 by 1385 cells at 1/24°.
s3://noaa-nclimgrid-monthly-pds7 catalogue datasets, 2 in preview
nClimGrid daily
NOAA NCEI
Contiguous US, about 5 km, 1951 to present. Precipitation, mean, min and max temperature.
s3://noaa-nclimgrid-daily-pds8 catalogue datasets
ERA5 (NSF NCAR curated)
ECMWF, curated by NSF NCAR
Global, 0.25°, hourly. Precipitation, temperature, humidity, wind, radiation.
s3://nsf-ncar-era526 catalogue datasets
CMIP6 projections
WCRP CMIP6
Global, model grids, historical and future scenarios. Precipitation, temperature and more, by model.
s3://cmip6-pds2 catalogue datasets
Your own data
You
Any grid or set of points with a time dimension. Map your variable names to precipitation and temperature.
An s3:// path or a local file
How datasets are made
- Inputs
- Read from public open-data registries such as the AWS Registry of Open Data, or from your own Zarr or NetCDF files. Each dataset is tied to the source it was generated from.
- Derived variables
- Thornthwaite PET from mean temperature and latitude feeds SPEI and the Palmer indices on nClimGrid. Sources with humidity, wind and radiation also allow Penman–Monteith reference evapotranspiration, which EDDI needs.
- Soil water
- The Palmer indices also need available water capacity. nClimGrid doesn’t include it, and the source grid is still to be chosen.
- Calibration
- Set per index and source. The available gamma SPI and SPEI calculations use 1950 to 2010; future products may differ.
- Validation and provenance
- Each index’s evidence is summarized on the Indices page and recorded in VALIDATION.md. Published files will record the climate_indices software version and parameters in their metadata.
- Attribution and updates
- Datasets are attributed to their sources. Current previews derive from NOAA Monthly U.S. Climate Gridded Dataset (nClimGrid), Vose et al. 2014, doi:10.7289/V5SX6B56; these are modified data and are not endorsed by NOAA. A monthly refresh is planned, and recent nClimGrid inputs may be revised by NCEI.
Tools for the planned files
xarray in a notebook
Open the Zarr store lazily and pull out a region, a month or a single location without downloading the rest.
xcube Viewer
Serve the Zarr store with xcube and browse it on a map, with time navigation and point time series.
Panoply
NASA's desktop viewer for NetCDF files. Good for quick maps and plots without writing code.