Changes in the Asian monsoon have affected emissions of methane from the Tibetan Plateau over the last 6,000 years, finds a new paper.
The concentration of methane in the atmosphere has more than doubled over the past century, though it is very short lived compared to carbon dioxide and hasn't been considered much of a factor in climate change. Factors in methane levels include leaks from gas wells, increased rice cultivation and ruminant animals in the dairy and meat industry. It could also be caused partly by climate change feedbacks on natural processes, but that remains the subject of intense investigation.
The results focus on a single wetland from the Tibetan Plateau that experienced strong climate variations over the past 6,000 years. They show that during relatively dry intervals, the biomass of methane-producing microorganisms decreased while methane-consuming microorganisms apparently became more efficient. The combined result would have been less methane emission to the atmosphere.
The Tibetan Plateau experienced strong climate variations over the past six thousand years. Credit: University of Bristol
According to project leader and Director of the University of Bristol Cabot Institute Professor Rich Pancost, "What we have done is connect the dots, providing strong evidence for previous researchers’ inferences. In modern settings, methane emissions from dryer settings are generally low. Consequently, previous researchers have speculated that as the Asian monsoon became weaker over the past six thousand years, methane emissions also decreased. Here, we show that this is exactly what happened to this peatland on the Tibetan Plateau."
The authors used a combination of chemical tools to reconstruct the past changes in microbial populations. First author Yanhong Zheng said, "All organisms have cell membranes but the molecules that comprise those membranes differ, especially for microorganisms; if these molecules are preserved in soils or sediments, they act as molecular fossils – or biomarkers – for those organisms in the past. We can then quantify them and that gives insight into ancient microbial communities."
The authors focused on archaeol, a compound that likely derives from methanogens (or methane-producing organisms) in these settings. During a dry interval from six to four thousand years ago, its concentration decreased by about 50 per cent, suggesting that the methane producing community became much smaller, probably because these organisms favor wet habitats.
Pancost added, "This is only a single site, but our study has wider implication for how these systems work. The dry interval we studied arose from large scale changes in atmospheric circulation patterns, and just as past changes impacted methane emissions, so will future climate change."
Citation: Yanhong Zheng, Joy S. Singarayer, Peng Cheng, Zhao Liu, Xuefeng Yu, Paul J. Valdes, Richard D. Pancost, 'Holocene variations in peatland methane cycling associated with the Asian summer monsoon system', Nature Communications
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Order Patterned With Chaos - How Climate Is Predicted For Decades - With Exact Forecasts Only For Days
- Is The X(5568) A True Resonance ?
- Chess is Smart and Sexy! The Mysterious Psychology of Chess Intelligence 1/3
- Should Pregnant Women Be Concerned About BPA?
- Baby Boomers Unbound: Marijuana Surges In The Elderly
- The Five Stages Of A Dying Theory
- Dormancy, Latency, Cannibalization - How Breast Cancer Can Suddenly Reappear
- "https://www.youtube.com/watch?v=TbqquQEvhok please watch this, explain that. ..."
- "Chris, the truth is that any website that uses the words Nibiru, Wormwood, or Death star is BS..."
- "Hi mr walker I'm proper scared about this nibiru nemesis wormwood death star they are adamant its..."
- "Thank you mr walker for your time and patience with you have been a big help. Dawn..."
- "Dawn, no there is nothing to be worried about at all. No need to warn anyone. It's just made up..."
- Paper Scandal at Science? Microbeads Lying In the Weeds. With A Stolen Computer.
- Honey, Please Pass The High Fructose Corn Syrup
- A stolen computer and the scandal of a high profile paper
- Need Some Zzzs? How Good Are The "Z" Sleeping Pills?
- Honey? Please.
- Environmentalists In Cancun: Gene Drives Will Cause Our Extinction, Now Pass The Caviar