The Human Impacts Database

A collection of useful numbers for quantifying the impacts of the human presence on Earth.

Global surface relative humidity change

Atmospheric & Biogeochemical CyclesWater Vapor

This quantity comes from a time series measurement and the most recent value (2019) is reported.

Value: -0.62 ± 0.29 %rh
HuID: 13406
Relevant Year(s): 2019
Summary: The global surface relative humidity change (or anomaly) with respect to the 1981-2010 reference period. Relative humidity is the ratio of specific humidity of the air to the specific humidity of saturated air at the same temperature. The change in global surface relative humidity is mainly driven by relative humidity changes over land. These changes are due to increasing surface temperatures with global warming and a tight coupling between the specific humidity of air over oceans and over land, see Byrne & O'Gorman, 2018. Data were obtained from the HadISDH.blend dataset.
Method: The HadISDH blend surface humidity dataset is computed by weighting and combining the HadISDH land and HadISDH marine datasets. Relative humidity is computed from temperature measurements and dew point data taken at stations over land and ICOADS observations from marine stations on ships, buoys, and ocean platforms. The anomalies are calculated with monthly resolution and averaged over 5° gridboxes. The 2 sigma uncertainty estimates represent the combination of sampling uncertainty, regional coverage uncertainty, and measurement uncertainty (which reflects uncertainties in climatology, measurement, and homogeneity adjustment).
Source: Met Office Hadley Centre HadISDH blend (land and marine) - gridded global surface humidity dataset. (2020)
Dataset: Contains time-series anomalies of land + marine relative humidity relative to 1981-2010. (HadISDH_relative_humidity_1973-2019.csv)
global resolution
Original Data License: OGL 3.0
Added By: nsarai