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Updated: Jul 11, 2026
08:20
In Situ Soil Moisture Sensors in Undisturbed Soils
Published on: November 18, 2022
Identification of human-induced changes in atmospheric moisture content
B D Santer1, C Mears, F J Wentz
1Program for Climate Model Diagnosis and Intercomparison, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA. santer1@llnl.gov
Summary
Global atmospheric moisture content has risen significantly since 1988, with climate models attributing this trend to human-caused greenhouse gas emissions, not natural variability.
Area of Science:
- Atmospheric Science
- Climate Science
- Remote Sensing
Background:
- Satellite data reveal a decadal increase in atmospheric moisture over oceans.
- Observed water vapor trends exceed natural climate variability.
- Previous studies lacked definitive attribution of observed moisture changes.
Purpose of the Study:
- To detect and attribute the causes of observed increases in atmospheric moisture.
- To differentiate between anthropogenic and natural factors influencing water vapor content.
- To provide evidence for an emerging anthropogenic signal in atmospheric moisture.
Main Methods:
- Analysis of Special Sensor Microwave Imager (SSM/I) satellite data from 1988 onwards.
- Formal detection and attribution analysis using pooled results from 22 climate models.
- Comparison of observed trends with climate model simulations under various forcing scenarios (greenhouse gases, solar forcing, volcanic recovery).
Main Results:
- A statistically significant increase of 0.41 kg/m(2) per decade in total atmospheric moisture over oceans was observed.
- The simulated "fingerprint" of anthropogenic water vapor changes was identified in SSM/I data with high confidence.
- Attribution analysis indicated that increased greenhouse gases are the primary driver, outweighing solar forcing or volcanic effects.
Conclusions:
- The observed increase in atmospheric moisture is primarily driven by human-induced greenhouse gas emissions.
- This study provides preliminary evidence of an emerging anthropogenic signal in Earth's atmospheric moisture content.
- Findings support the role of human activities in altering global water vapor levels.
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