Here is a short overview of the primary sources of methane. Some of these are relatively stable, long-term, but biogenic methane is increasing at an alarming rate.
Scientists haven’t proven “why”, but here are my explanations that I’d like you to consider.
Earth is resilient and so vast that it truly is hard to believe that mere mortals can have any real impact. But when our population just keeps on keeping on, and surging to some 8 billion souls now, the following sources of methane, which is some 25 times more potent than carbon dioxide, could explain why our atmosphere’s temperature has increased so quickly, at least in planetary terms. We are now up 1.2 centigrade, over about thirty years. In human terms that’s a slow increase. In planetary terms it might as well be instantaneous.
Back when the Great Extinction event occurred 252 million years ago, Earth’s atmosphere increased some 10oC, but over a 300,000-year period. Was it 30,000 years per degree? Not likely, but that’s the stuff of precise carbon dating. The key takeaway is that more than two thirds of species went away, became extinct during that short period, in terms of planetary timeline. We are getting a taste of the impact that just a one-degree shift can make, what with the dramatic weather and extinction events going on.
Here’s an incomplete list of methane that’s generated biologically…called biogenic methane. Note that the science around biogenic methane is incomplete. In my opinion, war criminals like Putin are likely to cause far more death than simple “engines of war” because he, and his admirers, are distracting us from the science needed to respond with effective climate action.
1. As Earth’s temperature bumps up, biologically generated methane (biogenic) trapped under frozen tundra is released. The volume is vast, but there is a mitigating factor: as the tundra warms up methanotrophs that consume methane also wake up. So the net effect is that about 82% of this inventoried methane is consumed, and released as simple carbon dioxide. Thank you, lord, for methanotrophs! In any case however, this source of methane could account for an important fraction of the current surge.
2. Bovines and such eat and belch methane. Hard to measure this one, but it’s a factor of some concern. I don’t get too excited about it though. Bovine populations haven’t expanded at the rate of the current increase, so this source probably does not account for the surge.
3. Landfill sites generate high localized volumes of biogenic methane. It’s not likely that this source can account for the recent surge in volume however, as it relates to population growth associated with humans and CAFOs. While populations continue to grow, they have not done so anywhere near the rate of the current surge.
4. Watersheds cycle nutrients through them. These nutrients grow biota. Based on this nutrient availability, today’s incidence of bio slime, think harmful algae bloom, has increased exponentially over the last several decades. When this organic material is consumed oxygen is used up. Under anaerobic conditions (without oxygen), methanogens generate methane. This is the same process that resulted in the Great Extinction event of 252 million years ago. I believe this is the primary reason biogenic methane concentrations in our atmosphere are surging.
Fresh water only represents about six percent of the Earth’s surface. But it’s where nutrients concentrate, along the bottom of watersheds. Scientists refer to this phenomenon as “wetland” derived biogenic methane, but in fact, every fresh water body, ponds, lakes, and reservoirs, are in the mix. They all can slip into anaerobic status and generate methane. Combined with fertilizers, these waterways are methane factories. Adding nutrients over and above fertilizers, think of the nutrients in waste water, storm water, and even fish food in the form of processed pellets, and you have a perfect storm of nutrients with which to burn through available oxygen.
Are we poised to deal with a ten-degree centigrade average increase in temperature? After seeing what happens with a 1.2oC increase, I know that I’m not ready. But I also know that we can respond and counteract the de-oxygenation cycle in nutrient impacted fresh water.
I believe that it is still early stage, in terms of Earth’s ability to fix the problem. Of course, Earth doesn’t see this as a problem…it just keeps on keeping on. But we mere mortals should take note, and respond. Russians should get their act together and deal with their bizarre leadership crisis. Politicians here in the west that aren’t climate aware should be dis-rewarded. The stakes are outrageously high.
Write something about yourself. No need to be fancy, just an overview.