Ifanadiana ERA5 Relative Humidity

Relative humidity represents the ratio between the quantity of water vapor present in the air and the maximum quantity the air can contain at a given temperature. Data are available from 2000 to 2023, with an initial spatial resolution of 11,132 meters. They are derived from the dew point temperature and the air temperature at 2 meters, according to the formula :

Relative Humidity = 100 * (exp((17.625 * TD) / (243.04 + TD)) / exp((17.625 * T) / (243.04 + T)))
where TD is the dew point temperature and T is the air temperature.

These data have been aggregated by Commune and Fokontany to calculate monthly averages, expressed as a percentage (%), where 100% indicates complete saturation of the air with water vapor.

DOI :
https://doi.org/10.1175/1520-0450(1996)0352.0.CO;2

Columns :
- fid : numeric id of commune or fokontany
- date : date in format: YYYY-MM, corresponding to year and month
- new_commune : commune name after 2019
- old_commune : commune name before 2019
- comm_fkt : name of fokontany using standardized ‘new_commune’_’fokontany’ nomenclature
- mean : average monthly relative humidity (%)

Data and Resources

Additional Info

Field Value
Source The data needed to calculate relative humidity comes from the following Google Earth Engine (GEE) collections: `ECMWF/ERA5_LAND/MONTHLY_AGGR`, and the bands used are `dewpoint_temperature_2m` and `temperature_2m`.
Author RANDRIANJATOVO Tokiniaina
Maintainer RANDRIANJATOVO Tokiniaina
Last Updated August 20, 2025, 14:06 (UTC)
Created July 16, 2025, 13:30 (UTC)
Data link : https://developers.google.com/earth-engine/datasets/catalog/ECMWF_ERA5_LAND_MONTHLY_AGGR#bands
Processing steps data aggregation using the spatial average of the polygon in each administrative zone