Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity
Syukuro Manabe, Richard T. Wetherald
Summary
Manabe and Wetherald developed a one-dimensional radiative-convective model of the atmosphere that, given a fixed distribution of relative humidity, computed the vertical temperature profile in thermal equilibrium. Incorporating realistic radiative transfer for water vapor, carbon dioxide, and ozone together with a convective adjustment, they estimated the surface and atmospheric temperature response to changes in CO₂. The study is widely regarded as the first physically based estimate of equilibrium climate sensitivity and demonstrated the central role of water-vapor feedback in amplifying CO₂-induced warming.
Key findings
- Holding relative humidity (rather than absolute humidity) fixed yields a strong positive water-vapor feedback that roughly doubles the warming compared with a fixed-absolute-humidity assumption.
- Doubling atmospheric CO₂ concentration produced an equilibrium surface warming of about 2.3–2.4 K in the model with average cloudiness.
- Increasing CO₂ warms the troposphere and surface while cooling the stratosphere, a characteristic vertical fingerprint of CO₂-driven climate change.
Subjects & keywords
Cite this paper
Syukuro Manabe, & Richard T. Wetherald (1967). Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity. Journal of the Atmospheric Sciences. https://doi.org/10.1175/1520-0469(1967)024<0241:TEOTAW>2.0.CO;2
@article{manabe1967thermal,
author = {Syukuro Manabe and Richard T. Wetherald},
title = {Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity},
journal = {Journal of the Atmospheric Sciences},
year = {1967},
doi = {10.1175/1520-0469(1967)024<0241:TEOTAW>2.0.CO;2},
url = {https://doi.org/10.1175/1520-0469(1967)024%3C0241:TEOTAW%3E2.0.CO;2}
}