First, what is it? “Methane is a chemical compound with the chemical formula CH4 (one atom of carbon and four atoms of hydrogen). It is a group-14 hydride and the simplest alkane, and is the main constituent of natural gas. The relative abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it poses technical challenges due to its gaseous state under normal conditions for temperature and pressure.
“Naturally occurring methane is found both below ground and under the seafloor, and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the atmosphere, it is known as atmospheric methane. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases.” Wikipedia. It is over 23 times denser than carbon dioxide (CO2), and even when it burns (adding oxygen), it leaves lots of CO2 in the atmosphere: CH4 + 2 O2 → CO2 + 2 H2O (residue is carbon dioxide and water).
Atmospheric methane is one of the biggest offenders in the acceleration of greenhouse gasses. In addition to the obvious leaks of that gas simply during extraction, transportation and utilization to generate power and heating/cooking, there are a number of issues buried in man’s responsibility for global warming. For example, in the massive Arctic tundra (think Siberia, Alaska, Canada, Greenland, Scandinavia, etc.) are huge cashes of methane trapped in frozen earth, generated by the aggregation of prehistoric organic matter over millennia. To the extent there is ice and snow remaining, this white surface deflects the sun’s rays (heat). When tundra melts (pictured above), it reveals darker land or seawater underneath, which absorbs heat and raises global temperatures accordingly. Hence, even more ice is melted, revealing more heat absorbing darkness, and the cycle becomes self-fulfilling and potentially never-ending until all that ice is gone.
But wait, greenhouse gas fans, there’s more. Aside from normal agricultural consequences – e.g., the massive emissions from cattle ranching – there are additional issues from surprising sources. Some of that menthane danger has always existed in nature… but an increasing amount is generated by human activity (anthropogenic). The Yale School of the Environment – in a study entitled Aquatic Ecosystems Source of Half of Global Methane Emissions – has made some startling conclusions, as noted in the April 9th edition of Yale News: “Atmospheric methane has tripled since pre-industrial times. It traps heat far more effectively than carbon dioxide and accounts for 25% of atmospheric warming to date.
“And much of that methane is coming from aquatic ecosystems, with human activities contributing to the emissions levels, a new paper published in Nature Geoscience has found… The global contribution and importance of aquatic ecosystems as methane emitters has been underestimated, says Judith Rosentreter, postdoctoral associate at the Yale School of the Environment (YSE) who led the study with a team of 14 researchers worldwide.
“The study authors reviewed methane fluxes from 15 major natural, human-made, and human-impacted aquatic ecosystems and wetlands, including inland, coastal, and oceanic systems. They found that when methane emissions are combined from these aquatic ecosystems, they are potentially a larger source of methane than direct anthropogenic methane sources, such as agriculture or fossil fuel combustion. Aquatic ecosystems and wetlands contribute at least as much as half of the total methane emissions budget.
“‘An accurate accounting of the sources of methane from aquatic ecosystems, and if they are impacted by human activities, is important to understanding atmospheric methane concentrations,’ says Peter Raymond, professor of ecosystem ecology who co-authored the study.
“One issue that stood out is how humans have impacted methane emissions from aquatic sources… ‘Anything human-driven or human-impacted had much higher fluxes than more natural sites,’’ says Rosentreter, a Yale Institute for Biospheric Studies Hutchinson Fellow.
“Globally, rice cultivation releases more methane per year than all coastal wetlands, the continental shelf and open ocean combined. Fertilizer runoff causes nutrient-rich lakes and reservoirs to release methane. Coastal aquaculture farms have methane fluxes per area that are 7-430 times higher than from non-converted coastal habitats, such as mangrove forests, salt marshes or seagrasses…
“‘Reducing methane emissions from aquatic systems will be an important part of stabilizing the Earth’s temperature,’’ says co-author Bradley Eyre Director, Centre for Coastal Biogeochemistry at Southern Cross University in Australia… Bringing awareness to the amount of methane emissions coming from aquaculture and other water systems can help inform new monitoring and measurements that identify where and how methane emissions are being produced and change over time… ‘With this awareness is also the possibility of helping to keep our waters cleaner,’ Rosentreter says.”
It is clear that there continue to be insufficient countermeasures against climate change within the major polluting nations. Our rejoining the Paris climate accord is profoundly inadequate. Global governmental and business forces continue to be unwilling to assess the trillions of dollars of hard dollar costs (many issues with long-term ramifications) against even the most flagrant emitters of greenhouse gasses. Instead, these governments reactively respond to the flooding, coastal surges, wildfires, amplifying cyclonic/hurricane destruction, devastating droughts, migration of disease carrying insects to climates more consistent with their biological design, and searing heat that will eventually render significant regions as uninhabitable. It is profoundly inefficient and much more expensive to react than prevent. While smaller efforts are being mounted globally, the timeline for full implementation falls short of stemming this existential threat.
I’m Peter Dekom, and the continued denial and marginalization of climate change, relating to its containment and reversal, will simply make cleaning up the damage vastly more costly – in hard dollars and human misery – than would be the job-creating commitment to prevention.
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