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How to measure atmospheric oxygen depletion

A new method to measure molecular oxygen depletion

This article is part of a series

This article is more for scientists and field researchers. It’s the conclusion of seventeen years of research and a practical step forward. I have created a novel method to measure whether atmospheric oxygen is rising or falling. It’s quite simple, but first, a little background.

Oxygen is hard to measure. There is a lot! It moves. It changes density with altitude and weather. And, maybe most importantly, the baseline sample was collected in 1985, well after the industrial revolution began burning oxygen in factories and automobiles. So, there’s little evidence for how much humanity has used. In a previous article, I discussed the difficulties and potential errors in the global oxygen measurement process.

Of course, after researching oxygen depletion for nearly two decades, I’d love to have a simple, easy solution. (Most of my research was determining if there is a problem.) One obvious solution is that we all need to stop burning fossil fuels immediately. But that’s a solution the whole world needs to agree on; and, unfortunately, despite the obvious threats of global warming society has done very little regarding climate change. So, the first step to any solution is to reach a critical mass of agreement. If we can conclusively prove that oxygen is declining at a faster rate than it is being replenished, at a rate that threatens life on Earth, it will be a more frightening scenario than global warming. I mean, it’s easier to imagine surviving a world that is too hot versus a world without air to breathe. And, so I think people will be more inclined to take action. 

That’s where my idea for a new method of measurement comes into play. After all this speculation, it’s a clear step forward. It’s a much more comprehensive measurement than simply comparing the ratio of oxygen to nitrogen, as is the current method.

Is there circumstantial evidence oxygen is declining? 

Before I present my answer, let’s look at some other possible solutions. Where in the world can we find evidence of oxygen depletion? And, if we find it, can we measure it?

Some ideas that I explored:

  • Is the tree line lower? Plants can suffocate. And if they are, we should notice a drop in the tree line worldwide as oxygen levels would drop faster at higher altitudes. 
  • Are pilots at high altitudes having difficulty remaining conscious? Likewise, are the planes performing at the same level? Are they using more fuel? If there is less oxygen, the performance of both humans and machines goes down.
  • Are oxygen concentrators failing?
  • Are anaerobic lifeforms thriving? 
  • Are people living at high altitudes struggling? Likewise, do mountain climbers use more supplemental oxygen?
  • Is there less oxygen in the northern hemisphere? Most industry (oxygen burning) is in the north, and the Earth’s air circulates faster from east to west rather than north to south. 
  • Is the troposphere rising or falling?
  • Are their inversion layers in the atmosphere trapping pockets of oxygen-depleted air?

These all seem like good ideas, but there is another layer to the problem that I discovered — oxygen levels in the atmosphere don’t appear to be changing much. That’s because some factors appear to be temporarily offsetting global warming and oxygen depletion. As we discussed here, those reasons are CO2 fertilization, oceans outgassing and glacial melt. 

We also discussed that current science doesn’t measure the mass of oxygen. It actually measures the ratio of oxygen to nitrogen at sea level. So, it’s possible that the oxygen at sea level remains constant while the level in the upper atmosphere drops, this is my fishbowl theory. And, it’s also possible for the ratio of nitrogen to oxygen to stay the same while the density goes down, or while the pollutants go up. This is related to partial pressure. Strangely, the atmosphere could be 100% oxygen, but if the pressure is too low, combustion and respiration would cease.

What happens if the world runs out of oxygen?

The article you are reading is based on years of research. The facts and science are real. However, in my new debut sci-fi novel, I extrapolate these ideas into the worst-case scenario: A firestorm devastates the Earth’s atmosphere, and a handful of survivors question whether it is worth saving themselves.

Will humanity survive the oxygen apocalypse? Find out now

The solution to measuring oxygen depletion

So, after much thinking, it popped into my head that to measure global oxygen depletion, we don’t need to know the total mass, but we do need to use a different ratio: To more accurately determine the rate of global oxygen depletion we need to measure the ratio between the oxygen levels in the atmosphere, ocean, land and ice (glaciers and polar caps), and then compare that to historical evidence.

To more accurately determine the rate of global oxygen depletion we need to measure the ratio between the oxygen levels in the atmosphere, ocean, land and ice (glaciers and polar caps), and then compare that to historical evidence.

By putting all these numbers together side-by-side and creating a ratio, it will be clear whether global oxygen is increasing or decreasing. For example, it is well known that the oceans are warming and outgassing (the stored oxygen is evaporating). So, if the oxygen levels in the atmosphere seem to remain constant, but the oxygen levels in the oceans are dropping, that means that in the future, when the oceans run out of surplus oxygen, the oxygen in the atmosphere will begin to decline dramatically.

Likewise, as glaciers and polar ice caps melt, they release their dissolved oxygen and trapped air bubbles. So, if we can calculate the reserve of oxygen in ice and how fast they are melting, we know how much oxygen is being pumped into the atmosphere. I’ve read hundreds of articles, and I’ve never read one on this topic. 

Land absorption is another measure of oxygen not widely talked about. Land absorbs a lot of oxygen — think rust. And as humankind mines the earth, builds cities, removes forests and till farmlands, they expose more land. The resulting erosion, desertification, and melting glaciers expose even more land. In other words, weathering absorbs huge amounts of oxygen — gigatonnes annually.* At the moment, plants seem to be thriving in this wetter, warmer world. But our ecosystems are in danger. We are losing plants, which make oxygen, and replacing them with land, which absorbs oxygen.

Scientists are measuring some of these things and comparing some ratios, particularly current atmospheric levels to historical oxygen levels. And, scientists are aware of the oxygen levels dropping in the ocean. But, they aren’t comparing all four of these things together. Again, we need a ratio of oxygen levels between air, land, sea and ice. Then we can compare this to historical records. 

Repeat photo of Grinnell Glacier showing glacial melt. In the 2016 image a lake is visible where before there was nothing but ice.
These side-by-side pictures show Grinnell Glacier in 1910 and 2016. It makes global warming look obvious. There are dozens of pictures like this from all over the world. USGS Repeat Photography Project.

Some tips on how to measure oxygen depletion

Creating a historical record of oxygen

This is already being done. Here are some potential sources of historical oxygen levels. 

  • Antarctic ice-cores. Scientists discovered that oxygen had gone down 0.7% in the last 800,000 and 0.1% in the previous 100 years.
  • Air bubbles trapped in 800-million-year-old rock salt.
  • Air bubbles trapped in amber. 
  • And there are many more complicated methods, such as determining ancient plant growth as a proxy measure. 

More importantly, we need measurements around the industrial era (the beginning of burning fossil fuels) to establish a baseline. The oldest sample of air that I am aware of is from 1985. Some ideas of where we can find modern samples of air:

  • Unopened caves and tombs.
  • Ancient bottles, perhaps upended in a shipwreck. 
  • Antique barometers. 
  • Like amber, maybe we could use the crystallized sap of very old trees. 
  • Or perhaps some of the oldest creatures on Earth carry evidence with them. Do they metabolize oxygen differently? Is it trapped in their cells? 
  • Are there oxygen isotopes that can be measured?
Global oxygen depletion logo. An illustration of the Earth  as a big O2 molecule.

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Improving the quantity of measurements

We need more measurements at different altitudes, depths and locations to create averages over time. Global warming and pollution are creating massive dead zones in the ocean. Scientists have only just begun to map ocean dead zones to determine if oxygen levels will go down as expected with global warming. (The previous article doesn’t mention how this might affect the atmosphere.) There may also be dead zones in the atmosphere, perhaps high above. Or the troposphere may be falling. And, the amount of dissolved and trapped air in the glaciers and polar caps is unknown. 

We also need to measure oxygen during the different seasons. (Oxygen tends to decrease in the winter.) Oxygen levels also go down at night because plants are using it for respiration. If there is a historical record of this, we may see the levels at night dropping even further.


I could elaborate greatly, but this is just an idea that I hope inspires further exploration in the scientific community. I’d be happy to help. 


See links above, plus:

This article discusses how glaciers and weathering caused a decline in global oxygen levels. Air bubbles in Antarctic ice point to a cause of oxygen decline.

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  1. Hi Scott,
    Interesting research. I came upon your site as I was thinking about the push for adopting hydrogen fuel. My company makes chemical sensors and we have a method to make a very accurate and portable oxygen sensor but there is not the market demand for such a device. Maybe things will change and then we can make your dream of understanding the state of the oxygen cycle more accurate and fill in this missing piece of the puzzle. Considering this change in atmospheric oxygen rate and the comment on one of your other posts it may be less than 500 years before we have an atmosphere that OSHA believes is unsafe.

    1. I do think hydrogen fuel would solve a lot of problems. I’m interested in how your oxygen sensor differs from the current method. I think we need to send them all over the world to create a map of the oxygen cycle. There are very few oxygen monitoring stations, whereas there must be thousands of CO2 monitoring stations. 500 years seems like a long time to find a solution, but I’m concerned that irreparable damage is occurring, or that we may reach an unforeseen tipping point. I’m including a link to your company in case anyone else is interested in this technology.

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