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Design and Use of a Full Flow Sampling System (FFS) for the Quantification of Methane Emissions
Published on: June 12, 2016
Continuing worldwide increase in tropospheric methane, 1978 to 1987
Science (New York, N.Y.)
|March 4, 1988
Summary
Global methane levels rose 11% between 1978 and 1987. This increase in tropospheric methane may have significantly boosted stratospheric water vapor, potentially impacting polar stratospheric cloud formation.
Area of Science:
- Atmospheric Chemistry
- Climate Science
Background:
- Methane is a potent greenhouse gas with increasing atmospheric concentrations.
- Tropospheric methane levels have shown a significant upward trend over recent decades.
Purpose of the Study:
- To analyze the trend of global tropospheric methane mixing ratios from 1978 to 1987.
- To investigate the potential impact of rising methane on stratospheric water vapor and polar stratospheric cloud formation.
Main Methods:
- Analysis of global atmospheric methane measurements.
- Statistical assessment of methane growth rates.
- Modeling potential stratospheric water vapor changes.
Main Results:
- Global average tropospheric methane increased by 11% (1.52 to 1.684 ppmv) from 1978 to 1987.
- The annual growth rate was approximately 0.016 ppmv/year, with a possible slight decrease in the last 5 years.
- No significant impact of El Niño-Southern Oscillation or El Chichón events on global methane was detected.
Conclusions:
- Rising tropospheric methane concentrations may have increased stratospheric water vapor by up to 45% over two centuries.
- This increase in stratospheric water could enhance the formation of polar stratospheric clouds.
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