Oxygen decline in Earth's atmosphere

Atmospheric Oxygen Decline threatens Humanity’s Existence

Study: There has been a clear decline in the volume of oxygen in Earth’s atmosphere over the past 20 years. A recently proposed model predicts a non-linear decay, which would result in an increasingly rapid fall-off in atmospheric oxygen concentration, with potentially devastating consequences for human health. 

We predict that humans may continue to survive in an unprotected atmosphere for ~3600 years.

The human physiological impact of global deoxygenation 

https://link.springer.com/article/10.1007/s12576-016-0501-0

Scripps O2 Global Oxygen Measurements http://scrippso2.ucsd.edu

Video footage via http://pixabay.com

Sound effects by http://EpicStockMedia.com and http://Soundmorph.com

Climate change decreases oxugen- Paul Beckwith

From Paul Beckwith

Oxygen Level Decrease in Air from Climate Change

Combustion of fossil fuels causes oxygen to decrease in the atmosphere/ocean system. As does deforestation, exponential population growth and phytoplankton loss in the oceans from warming stratification limiting nutrients at the surface. It is often said that the oxygen in every second breath you take is produced by photo plankton, that are the true lungs of the planet. I discuss the extend of the oxygen decrease, which is more than you want to know.

Please visit my website paulbeckwith.net and help support my videos/research (self-funded) via the Please Donate tab.

Falling Oxygen Levels a threat in abrupt climate change

"The researchers found that an increase in the water temperature of the world's oceans to about six degrees Celsius could stop oxygen production by phytoplankton by disrupting the process of photosynthesis."

Climate Change: Falling Oxygen Levels May be More Dangerous Than Flooding

Experts warn of crisis in the making in some provinces where extreme El Niño climate conditions have devastated crops

Science World Report ,

1 December, 2015

Falling oxygen levels caused by global warming could be a greater threat to the survival of life on Earth than flooding. Researchers have taken a closer look at the gas composition of our planet Earth and have found that organisms in our world's ocean could experience some major risks.

"Global warming has been a focus of attention of science and politics for about two decades now," said Sergei Petrovskii, one of the researchers, in a news release. "A lot has been said about its expected disastrous consequences; perhaps the most notorious is the global flooding that may result from melting of Antarctic ice if the warming exceeds a few degrees compared to the pre-industrial level. However, it now appears that this is probably not the biggest danger that the warming can cause to the humanity."

In this latest study, the researchers developed a new model of oxygen production in the ocean that takes into account basic interactions in the plankton community, such as oxygen production in photosynthesis, oxygen consumption because of plankton breathing and zooplankton feeding on phytoplankton.

The researchers found that an increase in the water temperature of the world's oceans to about six degrees Celsius could stop oxygen production by phytoplankton by disrupting the process of photosynthesis.

"About two-thirds of the planet's total atmospheric oxygen is produced by ocean phytoplankton-and therefore cessation would result in the depletion of atmospheric oxygen on a global scale," said Petrovskii. "This would likely result in the mass mortality of animals and humans."

The findings reveal that when it comes to global warming, flooding may not be the only danger to watch out for

The findings are published in the journal Bulletin of Mathematical Biology.

O2 Dropping Faster than CO2 Rising - Implications for Climate Change Policies

New research shows oxygen depletion in the atmosphere accelerating since 2003, coinciding with the biofuels boom; climate policies that focus exclusively on carbon sequestration could be disastrous for all oxygen-breathing organisms including humans Dr. Mae-Wan Ho

The dying Baltic Sea

Oxygen depletion in the Baltic Sea is ten times worse than a century ago

When the oxygen content in the bottom water reaches a low point, the only survivors are ultimately bacteria that live on and in the seabed. Here the patches of white sulfur bacteria form a shroud.   Credit: Photo: Peter Bondo Christensen

Science Daily,

26 January, 2013

Date: March 31, 2014

Source: Aarhus University

Summary:

The Baltic Sea is suffering from a lack of oxygen. Poor oxygen conditions on the seabed are killing animals and plants, and experts are now sounding the alarm -- releasing fewer nutrients into the Baltic Sea is absolutely necessary. The deepest areas of the Baltic Sea have always had a low oxygen content. The inflow of fresh water is actually limited by low thresholds at the entrance to the Baltic Sea. At the same time, there is a relatively fresh layer above the denser and saltier water in the deep layer of the sea. This results in an effective stratification of the water column, which prevents the mixing of water masses necessary to transfer oxygen to the water at the bottom.

The Baltic Sea is suffering from a lack of oxygen. Poor oxygen conditions on the seabed are killing animals and plants, and experts are now sounding the alarm -- releasing fewer nutrients into the Baltic Sea is absolutely necessary. 

After several years of discussions, researchers from Aarhus University (Denmark), Lund University (Sweden) and Stockholm University (Sweden) have determined that nutrients from the land are the main cause of widespread areas of oxygen depletion. The results were published on 31 March in the journal Proceedings of the National Academy of Sciences.

Nutrients are the villain

The deepest areas of the Baltic Sea have always had a low oxygen content. The inflow of fresh water is actually limited by low thresholds at the entrance to the Baltic Sea. At the same time, there is a relatively fresh layer above the denser and saltier water in the deep layer of the sea. This results in an effective stratification of the water column, which prevents the mixing of water masses necessary to transfer oxygen to the water at the bottom.

During the last century, the areas of oxygen depletion have increased drastically from approximately 5,000 km² in around 1900 to the present day, where they extend to 60,000 km² -- or about one and a half times the total area of Denmark.

"We analysed data for the water temperature, oxygen content and salinity stretching back for 115 years. On the basis of this analysis, we can determine that the many nutrients from the land are the main cause of the widespread oxygen depletion," says Professor Jacob Carstensen, Department of Bioscience, Aarhus University.

Seabed without oxygen

Oxygen depletion occurs when the oxygen uptake at the bottom exceeds the amount of oxygen brought to the deeper water layers via currents and mixing by the wind.

During the last twenty years, climate change has also played a role in the poor oxygen situation. Warmer conditions reduce the solubility of oxygen from the atmosphere and increase oxygen consumption because the biological respiration processes are boosted.

"The water temperature has risen and will continue to rise in the years ahead. It's therefore extra important that all the countries surrounding the Baltic Sea are committed to the Baltic Sea action plan they joined, and that they comply with the necessary efforts to reduce the release of nutrients into the Baltic," emphasises Professor Carstensen, who is also director of the Baltic Nest Institute in Denmark.

Oxygen depletion on the seabed has a negative impact on the entire ecosystem. This is partly because the seabed turns into a 'desert' inhabited only by bacteria that can survive without or with very low amounts of oxygen. Some bacteria produce methane, which can bubble up to the water and tear large areas of the toxic, hydrogen sulphide-rich seabed with it. This involves sediment disturbances that can kill fish high up in the water column.

Studies show that it takes decades before benthic fauna once more return to a dead seabed when the oxygen conditions improve.

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Story Source:

The above story is based on materials provided by Aarhus University. Note: Materials may be edited for content and length.

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Journal Reference:

1. Jacob Carstensen, Jesper H. Andersen, Bo G. Gustafsson, and Daniel J. Conley.Deoxygenation of the Baltic Sea during the last century. PNAS, March 31, 2014 DOI: 10.1073/pnas.1323156111