Very High Greenhouse Gas Levels

Carbon Dioxide

On June 1, 2020, NOAA recorded a daily average carbon dioxide (CO₂) level of 418.32 ppm at Mauna Loa, Hawaii.

The image below shows hourly average CO₂ levels approaching 419 ppm at Mauna Loa on May 1, 2020.

The image below shows hourly (red circles) and daily (yellow circles) averaged CO₂ values at Mauna Loa, Hawaii over 31 days, up to May 31, 2020, with some recent hourly averages showing up with values exceeding 419 ppm.

The image below shows hourly (red circles) and daily (yellow circles) averaged CO₂ values at Mauna Loa, Hawaii over 31 days, through June 1, 2020, when a daily average of 418.32 ppm was recorded.

By comparison, the highest daily average CO₂ level recorded by NOAA in 2019 at Mauna Loa was 415.64 ppm, as discussed in an earlier post. The image below shows how CO₂ growth has increased over the decades.

As illustrated by the image below, the daily average CO₂ on June 1, 2019, was 414.14 ppm and the daily average CO₂ on June 1, 2020, was 418.32 ppm, i.e. 4.18 ppm higher. The average in May 2019 was 414.65 ppm and the average in May 2020 was 417.07 ppm, i.e. 2.42 ppm higher. Since the annual maximum is typically reached in May, this high reading for June 1, 2020, could indicate that, while CO₂ emissions by people were suppressed in April and May 2020 due to the COVID-19 lockdowns, growth of CO₂ levels in the atmosphere continues to speed up now as restrictions are relaxed.

Even more significant than the daily averages could be the hourly averages. The daily average CO₂ level recorded by scripps.ucsd.edu at Mauna Loa, Hawaii, was 418.04 ppm on May 25, 2020. On May 24, 2020, one hourly average exceeded 420 ppm, at which time emissions by people had raised CO₂ levels by some 160 ppm compared to the situation thousands of years ago, and by even more if levels had continued to follow a natural trend, as illustrated by the image and inset below.

A rise of 100 ppm CO₂ has historically corresponded with a global temperature rise of some 10°C or 18°F, when looking at CO₂ levels and temperatures over the past 420,000 years, as illustrated by the image below.

Concentrations of carbon dioxide, methane (CH₄) and nitrous oxide (N₂O) in 2018 surged by higher amounts than during the past decade, according to a 2019 WMO news release and as illustrated by the image on the right, from an earlier post, which shows that CH₄, CO₂ and N₂O levels in the atmosphere in 2018 were, respectively, 259%, 147% and 123% of their pre-industrial (before 1750) levels.

So, methane levels have been rising much faster than CO₂ since 1750 and there is much potential for an even faster rise in methane levels due to seafloor hydrate releases.

Furthermore, as industrial activity declines in the wake of COVID-19, loss of aerosol masking alone could trigger a rapid rise, as discussed by Guy McPherson in recent papers here and here.

Given this, the 160 ppm rise in CO₂ could lead to a global temperature rise of 18°C or 32.4°F from 1750, and such a rise could unfold soon, as oceans and ice take up ever less heat and further feedbacks kick in, as also discussed in earlier post such as this one and this one.

Levels for methane and nitrous oxide were very high in May 2020, as further discussed below.

Methane

MetOp-1 recorded peak methane levels of 2917 ppb at 469 mb on the afternoon of May 22, 2020.

MetOp-1 recorded mean methane levels of 1896 ppb at 336 mb on the morning of May 22, 2020.

MetOp-2 recorded peak methane levels of 1918 ppb at 586 mb on the afternoon of May 24, 2020.

Nitrous Oxide

N20 recorded peak nitrous oxide levels of 366 ppb at 840 mb on the morning of May 21, 2020.

N20 recorded somewhat lower peak nitrous oxide levels of 346.9 ppb at 487.2 mb on the afternoon of May 23, 2020, but look at how much of Antarctica is covered by the magenta color, reflecting levels at the top end of the scale.

Rising greenhouse gas levels are damaging the ozone layer

Nitrous oxide is both a potent greenhouse gas and an ozone depleting substance that is thus directly damaging the ozone layer.

Additionally, rising greenhouse gas levels are indirectly damaging the ozone layer in three ways:

Firstly, rising greenhouse gas levels are making water vapor enter the stratosphere. Higher sea surface temperatures along the path of the Gulf Stream fuel hurricanes traveling north along North America's east coast. More heat also translates into more wind; stronger hurricanes are getting stronger over the years.

Rising levels of greenhouse gases strengthen winds and increase water vapor in the atmosphere. Temperatures are rising faster in the Arctic than in the rest of the world, as illustrated by the image below, and this is changing the Jet Stream.

[ click on images to enlarge ]

Jennifer Francis has long pointed out that, as temperatures at the North Pole are rising faster than at the Equator, the Jet Stream is becoming wavier and can get stuck in a 'blocking pattern' for days, increasing the duration and intensity of extreme weather events. This can result in stronger storms moving more water vapor inland over the U.S., as discussed in earlier posts such as this one. Such storms can cause large amounts of water vapor to rise high up in the sky. Water vapor that enters the stratosphere can damage the ozone layer.

Secondly, as plumes above the anvils of severe storms bring water vapor up into the stratosphere, this also contributes to the formation of cirrus clouds that trap a lot of heat that would otherwise be radiated away, from Earth into space.

Thirdly, higher temperatures and stronger winds increase the intensity of droughts. Heatwaves combined with strong winds, dry soil and dry vegetation can make forest fires produce smoke that can enter the stratosphere and stay there for along time.

Recent examples of extreme weather events are described below, i.e. a huge storm and a heatwave in the Arctic.

Super Typhoon Amphan hits India and Bangladesh

Also in May 2020, super typhoon Amphan hit India and Bangladesh, with high waves and heavy rainfall. Waves as high as 14.2 m or 46.6 ft were forecast (at the green circle) for May 20, 2020, 06:00 UTC as Amphan approached Bangladesh.

"Once once-in-a-century, now once-in-a-decade", comments Sam Carana on this and other events.

The sea surface temperature image below shows that, on May 17, 2020, ocean temperatures were as high as 32.9°C or 91.1°F.

The combination image below shows high sea surface temperatures on May 15, 2020, 12:00 UTC, in the left panel.

Anomalies in the Indian Ocean were as high as 3.4°C or 6.0°F, in the Arctic Ocean as high as 1°C or 1.8°F and in the Pacific Ocean as high as 5.1°C or 9.1°F. Anomalies are from daily average during years 1981-2011.

The right panel of the combination image shows how these high ocean temperatures cause circular wind patterns. Wind speed was as high as 255 km/h or 159 mph in the Indian Ocean, at the location of super typhoon Amphan, on May 18, 2020, 06:00 UTC, while instantaneous wind power density was as high as 177.2 kW/m².

The combination image below shows the temporary cooling impact of Amphan.

The bottom panel shows that on May 18, 2020 09:00 UTC, the temperature at a location in India was 42.6°C or 108.6°F, as Amphan was approaching from the South.

The middle panel shows that, two days later, at the same location and at same time of day, the temperature had fallen to 23.4°C or 74°F as Amphan hit the area.

The cooling is only temporary. The top panel shows that a temperature of 47.9°C or 118.1°F is forecast for that location, same time of day, for May 26, 2020.

Siberian Heatwave

A heatwave hit Siberia in May 2020.

Above image shows that temperature anomalies were forecast to be at the high end of the scale over Siberia on May 22, 2020, 06:00 UTC, i.e. 30°C or 54°F higher than 1979-2000. At the same time, cold temperatures are forecast for much of eastern Europe.

What enables such a strong heatwave to develop is that the Jet Stream is getting more wavy as the temperature difference between the North Pole and the Equator is narrowing, causing both hot air to move up into the Arctic (red arrow) and cold air to descend out of the Arctic (blue arrow).

The Siberian heatwave threatens to trigger forest fires that can cause large amounts of black carbon to settle on the snow and ice cover, speeding up its demise. Furthermore, the heatwave threatens rivers to heat up that carry large amounts of water into the Arctic Ocean. Finally, as discussed, more intense forest fires threaten to cause organic carbon compounds to enter the stratosphere.

Extinction mechanism

A recent study by John Marshall et al. found that the Devionian mass extinction event 360 million years ago, that killed much of the Earth's plant and freshwater aquatic life, was caused by a brief breakdown of the ozone layer. John Marshall says: "Current estimates suggest we will reach similar global temperatures to those of 360 million years ago, with the possibility that a similar collapse of the ozone layer could occur again, exposing surface and shallow sea life to deadly radiation. This would move us from the current state of climate change, to a climate emergency."

John refers to the work by James Anderson et al., who warn that CO₂ and CH₄ release from clathrates and permafrost could cause more water to get carried into the stratosphere. John further describes the 'Extinction mechanism': "High summer temperatures over continental areas can increase the transport of water vapour high into the atmosphere. This water vapour carries with it organic carbon compounds that include chlorine, which are produced naturally by a wide variety of plants, algae and fungi. Once these compounds are near the ozone layer, they release the chlorine and this breaks down ozone molecules. This produces a positive feedback loop because a collapsing terrestrial ecosystem will release a flush of nutrients into the oceans, which can cause a rapid increase in algae."

Arctic sea ice volume

As Guy McPherson points out, COVID-19 alone could trigger an abrupt huge temperature rise.

Furthermore, loss of Arctic sea ice could cause a rapid temperature rise.

Ominously, Arctic sea ice volume has been at record low since the start of 2020, while 2019 volume was at a record low from October, making that volume has now been at record low for almost 8 months straight.

The situation is dire and calls for immediate, comprehensive and effective action as described in the Climate Plan.


Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• Climate Plan (June 1, 2019 version)
https://arctic-news.blogspot.com/2019/06/climate-plan.html

• The Keeling Curve - Scripps Institution of Oceanography at UC San Diego
https://scripps.ucsd.edu/programs/keelingcurve

• 417.93 parts per million (ppm) CO2 in air 24-May-2020
https://twitter.com/Keeling_curve/status/1264955470655025152

• Greenhouse Gas Levels Keep Accelerating
https://arctic-news.blogspot.com/2019/05/greenhouse-gas-levels-keep-accelerating.html

• Will COVID-19 Trigger Extinction of All Life on Earth? - by Guy McPherson
https://opastonline.com/wp-content/uploads/2020/04/will-covid-19-trigger-extinction-of-all-life-on-earth-eesrr-20-.pdf

• Earth is in the Midst of Abrupt, Irreversible Climate Change - by Guy McPherson
https://www.onlinescientificresearch.com/articles/earth-is-in-the-midst-of-abrupt-irreversible-climate-change.pdf

• Extinction
https://arctic-news.blogspot.com/p/extinction.html

• Most Important Message Ever
https://arctic-news.blogspot.com/2019/07/most-important-message-ever.html

• Methane
https://arctic-news.blogspot.com/p/methane.html

• Study shows erosion of ozone layer responsible for mass extinction event
https://www.eurekalert.org/pub_releases/2020-05/uos-sse052620.php

• UV-B radiation was the Devonian-Carboniferous boundary terrestrial extinction kill mechanism - by John Marshall et al.
https://advances.sciencemag.org/content/6/22/eaba0768

• Prehistoric climate change damaged the ozone layer and led to a mass extinction - by John Marshall
https://theconversation.com/prehistoric-climate-change-damaged-the-ozone-layer-and-led-to-a-mass-extinction-139519

• UV Dosage Levels in Summer: Increased Risk of Ozone Loss from Convectively Injected Water Vapor - by James Anderson et al.
https://science.sciencemag.org/content/337/6096/835

• Care for the Ozone Layer
https://arctic-news.blogspot.com/2019/01/care-for-the-ozone-layer.html

• Why stronger winds over the North Atlantic are so dangerous
https://arctic-news.blogspot.com/2020/02/why-stronger-winds-over-north-atlantic-are-so-dangerous.html

• A Global Temperature Rise Of More than Ten Degrees Celsius By 2026?
https://arctic-news.blogspot.com/2016/07/a-global-temperature-rise-of-more-than-ten-degrees-celsius-by-2026.html

• Forces behind Superstorm Sandy
https://arctic-news.blogspot.com/2012/11/forces-behind-superstorm-sandy.html

• April 2020 temperatures very high
https://arctic-news.blogspot.com/2020/05/april-2020-temperatures-very-high.html

• Could Humans Go Extinct Within Years?
https://arctic-news.blogspot.com/2020/01/could-humans-go-extinct-within-years.html

• Arctic Ocean November 2019
https://arctic-news.blogspot.com/2019/11/arctic-ocean-november-2019.html

Greenhouse Gas Levels Keep Accelerating

Carbon Dioxide

Weekly CO₂ (carbon dioxide) levels at Mauna Loa, Hawaii, in May, 2019, reached 415.39 ppm, as above image shows. An ominous trendline points at 420 ppm in 2020.

The daily average CO₂ level recorded by NOAA at Mauna Loa, Hawaii, on May 15, 2019, was 415.64 ppm, as above image shows. The image below also shows hourly average levels from April 15, 2019, to May 15, 2019.

Current CO₂ levels far exceed levels that were common during the past 800,000 years, as the image below shows. CO₂ levels moved between roughly 180 and 280 ppm, while the temperature went up and down by some 10°C or 18°F.

The daily average CO₂ level recorded by scripps.ucsd.edu at Mauna Loa, Hawaii, on May 13, 2019, was 415.5 ppm and the May 15, 2019, level was 415.7 ppm. On May 14, 2019, one hourly average exceeded 417 ppm.

The situation is dire

This level of 417 ppm is 139 ppm above the CO₂ level in the year 1750 and more than 157 ppm above what the CO₂ level would have been if levels had followed a natural trend. As shown by the inset (from Ruddiman et al.) in above image, a natural trend points at levels below 260 ppm.

Furthermore, methane levels are rising even faster than CO₂ levels. While CO₂ levels did rise by 146% since 1750, methane levels did rise by 257% since that time and there is much potential for an even faster rise in methane levels due to seafloor hydrate releases. Levels of nitrous oxide also keep rising rapidly.

Such a rise in greenhouse gas levels has historically corresponded with more than 10°C or 18°F of warming, when looking at greenhouse gas levels and temperatures over the past 420,000 years, as illustrated by the image below.

Given that a 100 ppm rise in CO₂ did historically cause temperatures to rise by 10°C or 18°F, how much warming would be in line with a 157 ppm CO₂ and how fast could such a rise unfold?

A temperature of 10°C or 18° above 1750 seems in line with such high greenhouse gas levels. This is illustrated by above graph, based on 420,000 years of ice core data from Vostok, Antarctica, and as the post What Does Abrupt Climate Change Look Like? describes.

Why isn't it much warmer now? Why hasn't such a rise happened yet? Oceans and ice are still holding off such a rise, by absorbing huge amounts of warming. Of 1993-2003 warming, 95.5% was absorbed by oceans and ice. However, ocean stratification and ice loss are making the atmosphere take up more and more heat.

There are further warming elements, in addition to the accelerating rise in greenhouse gas levels. Mentioned above is the loss of the snow and ice cover. The domino effect is a popular way to demonstrate a chain reaction. It is typically sequential and typically uses dominoes that are equal in size. A chain reaction can be achieved with solid dominoes each as much as 1.5 times larger than the previous one. The exponential function is discussed in the video below by Guy McPherson. Rather than following a linear order, warming elements can be self-reinforcing feedback loops and can influence each other in ways that multiply (rather than pass on) their impact, which can speed up the temperature rise exponentially.

So, how fast and by how much could temperatures rise? As oceans and ice are taking up ever less heat, rapid warming of the lower troposphere could occur very soon. When including the joint impact of all warming elements, as described in a recent post, abrupt climate change could result in a rise of as much as 18°C or 32.4°F by 2026. This could cause most life on Earth (including humans) to go extinct within years.

Methane

Next to carbon dioxide, there are further greenhouse gases. Methane is important, because of its high short-term potency as a greenhouse gas and because methane levels in the atmosphere have hugely risen since 1750, and especially recently, as illustrated by the image on the right.

Carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) levels in the atmosphere in 2017 were, respectively, 257%, 146% and 122% their 1750 levels.

A recent study by Turetsky et al. concludes that, since sudden collapse releases more carbon per square metre because it disrupts stockpiles deep in frozen layers, and since abrupt thawing releases more methane than gradual thawing does, the impact of thawing permafrost on Earth’s climate could be twice that expected from current models.

As said, there also is a huge and growing danger of large abrupt methane releases from clathrates contained in sediments at the seafloor of the Arctic Ocean.

As illustrated by the image below, methane levels are rising and this rise is accelerating.

The graph shows July 1983 through December 2018 monthly global methane means at sea level, with added trend. Higher methane means can occur at higher altitude than at sea level. On Sep 3, 2018, daily methane means as high as 1905 ppb were recorded at 307 mb, an altitude at which some of the strongest growth in methane has occurred, as discussed in earlier posts such as this one.

The recent rise in methane is the more worrying in the light of recent research that calculates that methane's radiative forcing is about 25% higher than reported in IPCC AR5, implying that methane's GWP (global warming potential) over 10 years may be well over 150 times as much as CO₂.

Nitrous Oxide

Next to carbon dioxide and methane, there are further greenhouse gases, of which nitrous oxide is particularly important. Nitrous oxide is up to 300 times as potent as a greenhouse gas as carbon dioxide and has a lifetime of 121 years. Several recent studies point at the danger of huge releases of nitrous oxide from permafrost.

According to a 2017 study by Voigt et al., Arctic permafrost contains vast amounts of nitrogen (more than 67 billion tons). Warming of the Arctic permafrost is accelerating, causing rapid thaw of permafrost soils, and this now threatens to cause huge releases of nitrous oxide to the atmosphere. The study concluded that nitrous oxide emissions in the Arctic are likely substantial and underestimated, and show high potential to increase with permafrost thaw.

In the video below, Paul Beckwith discusses nitrous oxide.

In the video below, Paul Beckwith discusses the recent study by Wilkerson et al.

The study by Wilkerson et al. shows that nitrous oxide emissions from thawing Alaskan permafrost are about twelve times higher than previously assumed. A 2018 study by Yang et al. points at the danger of large nitrous oxide releases from thawing permafrost in Tibet. Even more nitrous oxide could be released from Antarctica. The danger is illustrated by the image below, which shows that massive amounts of nitrous oxide were recorded over Antarctica on April 29, 2019.

Depletion of the Ozone Layer

In addition to being a potent greenhouse gas, nitrous oxide is also an ozone depleting substance (ODS). As the left panel of the image below shows, growth in the levels of chlorofluorocarbons (CFCs) has slowed over the years, yet their impact will continue for a long time, given their long atmospheric lifetime (55 years for CFC-11 and 140 years for CFC-12). Since nitrous oxide levels continue to increase in the atmosphere, while the impact of CFC-11 and CFC-12 is slowly decreasing over time, the impact (as an ODS) of nitrous oxide has relatively grown, as the right panel of the image below shows.

[ from an earlier post ]

James Anderson, co-recipient of the 1995 Nobel Prize in chemistry for his work on ozone depletion, said in 2018 that "we have five years to save ourselves from climate change".

Comprehensive Action

In conclusion, while it's important to reduce emissions of all greenhouse gases, reducing emissions of methane and nitrous oxide is particularly important. To both reduce polluting emissions and to remove greenhouse gases from the atmosphere and oceans, the Climate Plan recommends feebates as depicted in the image below. As the image also mentions, further lines of action will be needed to avoid a rapid rise in temperature.

[ from an earlier post ]

Meanwhile, Arctic sea ice reached a new record low for April, as illustrated by the NSIDC image below.

In the video below, Guy McPherson describes what threatens to eventuate soon. This is an edit of the April 22, 2019, video in which Guy McPherson was interviewed by Peter B. Collins for the community television station in Marin County, California.

In the video below, Guy McPherson gives a presentation at the Center for Spiritual Living, in Chico, April 28, 2019.

The situation is dire and calls for comprehensive and effective action as described in the Climate Plan.


Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• Permafrost collapse is accelerating carbon release, by Merritt Turetsky et al. (30 April 2019)
https://www.nature.com/articles/d41586-019-01313-4

• Permafrost nitrous oxide emissions observed on a landscape scale using the airborne eddy-covariance method, by Jordan Wilkerson et al. (April 3, 2019)
https://www.atmos-chem-phys.net/19/4257/2019/

• Can natural or anthropogenic explanations of late-Holocene CO2 and CH4 increases be falsified?, by William Ruddiman et al. (2011)
https://journals.sagepub.com/doi/10.1177/0959683610387172

• Radiative forcing of carbon dioxide, methane, and nitrous oxide: A significant revision of the methane radiative forcing, by Etminan et al. (2016)
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL071930

• Magnitude and Pathways of Increased Nitrous Oxide Emissions from Uplands Following Permafrost Thaw, by Guibiao Yang et al. (July 9, 2018)
https://pubs.acs.org/doi/10.1021/acs.est.8b02271

• Increased nitrous oxide emissions from Arctic peatlands after permafrost thaw, by Carolina Voigt et al.
https://www.pnas.org/content/early/2017/05/23/1702902114

• We Have Five Years To Save Ourselves From Climate Change, Harvard Scientist Says - James Anderson (January 15, 2018)
https://www.forbes.com/sites/jeffmcmahon/2018/01/15/carbon-pollution-has-shoved-the-climate-backward-at-least-12-million-years-harvard-scientist-says/

• A rise of 18°C or 32.4°F by 2026?
https://arctic-news.blogspot.com/2019/02/a-rise-of-18c-or-324f-by-2026.html

• Care for the Ozone Layer
https://arctic-news.blogspot.com/2019/01/care-for-the-ozone-layer.html

• What Does Runaway Warming Look Like?
https://arctic-news.blogspot.com/2018/10/what-does-runaway-warming-look-like.html

• Rapid ice loss in early April leads to new record low - NSIDC
https://nsidc.org/arcticseaicenews/2019/05/rapid-ice-loss-in-early-april-leads-to-new-record-low/

Care for the Ozone Layer

The stratosphere normally is cold and very dry. Global warming can increase water vapor in the stratosphere in a number of ways. Global warming causes the troposphere to warm and since warmer air holds more water vapor, the amount of water vapor in the troposphere is increasing. This can cause more water vapor to end up in the stratosphere as well, as described below.

Stratospheric Water Vapor over the Arctic

Around the time of the December Solstice, very little sunlight is reaching the Arctic and temperatures over land at higher latitudes can get very low. At the same time, global warming has made oceans warmer and this keeps air temperatures over water relatively warm in Winter. This can lead to a number of phenomena including sudden stratospheric warming and moistening of the stratosphere.

Sudden stratospheric warming is illustrated by the image on the right, showing temperatures in the stratosphere over Siberia as high as 12.7°C or 54.9°F on December 24, 2018, and temperatures as low as -84.8°C or -120.6°F over Greenland.

At the same time, relative humidity was as high as 100% in the stratosphere over the North Sea, as the second image on the right shows.

Moistening of the stratosphere was even more pronounced on December 24, 2016, as illustrated by the third image on the right.

Storms over the U.S.

Jennifer Francis has long pointed out that, as temperatures at the North Pole are rising faster than at the Equator, the Jet Stream is becoming wavier and can get stuck in a 'blocking pattern' for days, increasing the duration and intensity of extreme weather events.

This can result in stronger storms moving more water vapor inland over the U.S., and such storms can cause large amounts of water vapor to rise high up in the sky.

Water vapor reaching stratospheric altitudes causes loss of ozone, as James Anderson describes in a 2017 paper and discusses in the short 2016 video below.

Methane

Stratospheric water vapor can also result from methane oxidation in the stratosphere. Methane concentrations have risen strongly at higher altitudes over the years. Noctilucent clouds indicate that methane has led to water vapor in the upper atmosphere.

The danger is that, as the Arctic Ocean keeps warming, large eruptions of methane will occur from the seafloor. Ominously, high methane levels have recently shown up on satellite images over the Arctic at lower altitudes, indicating the methane is escaping from the sea.

The images below show methane levels recorded by the NPP satellite:
Jan. 6, 2019, with peak levels of 2513 ppb at 1000 mb, 2600 ppb at 840 mb and 2618 ppb at 695 mb;
Jan. 11, 2019, with peak levels of 2577 ppb at 1000 mb, 2744 ppb at 840 mb and 2912 ppb at 695 mb;
Jan. 15, 2019, with peak levels of 2524 ppb at 1000 mb, 2697 ppb at 840 mb and 2847 ppb at 695 mb.
















The images below show methane levels recorded by the MetOp satellites:
Jan. 15, 2019, with peak levels of 2177 ppb at 840 mb, 2342 ppb at 695 mb and 2541 ppb at 586 mb;
Jan. 16, 2019, with peak levels of 2219 ppb at 840 mb, 2299 ppb at 695 mb and 2475 ppb at 586 mb;
Jan. 19, 2019, with peak levels of 2201 ppb at 840 mb, 2489 ppb at 695 mb and 2813 ppb at 586 mb.

 

The Importance of the Ozone Layer

Increases in stratospheric water vapor are bad news, as they speed up global warming and lead to loss of stratospheric ozone, as Drew Shindell pointed out back in 2001.

It has long been known that deterioration of the ozone shield increases ultraviolet-B irradiation, in turn causing skin cancer. Recent research suggest that, millions of years ago, it could also have led to loss of fertility and consequent extinction in plants and animals (see box right).

Nitrous oxide

As the left panel of the image below shows, growth in the levels of chlorofluorocarbons (CFCs) has slowed over the years, but their impact will continue for a long time, given their long atmospheric lifetime (55 years for CFC-11 and 140 years for CFC-12, CCl2F2).

Furthermore, as the right panel shows, the impact of nitrous oxide (N₂O) as an ozone depleting substance (ODS) has relatively grown, while N₂O levels also continue to increase in the atmosphere.

[ click on images to enlarge ]

Existential Threats

In conclusion, rising levels of emissions by people constitute existential threats in many ways. Rising temperatures cause heat stress and infertility, and there are domino effects. Furthermore, stratospheric ozone loss causes cancer and infertility.

Only once the ozone layer formed on Earth some 600 million years ago could multicellular life develop and survive. Further loss of stratospheric ozone could be the fastest path to extinction for humanity, making care for the ozone layer imperative.

As described in an earlier post, Earth is on the edge of runaway warming and in a moist-greenhouse scenario oceans evaporate into the stratosphere with loss of the ozone layer.

The situation is dire and calls for comprehensive and effective action, as described in the Climate Plan.


Links

• Climate and ozone response to increased stratospheric water vapor, by Drew Shindell (2001)
https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/1999GL011197

• Stratospheric ozone over the United States in summer linked to observations of convection and temperature via chlorine and bromine catalysis, by James Anderson et al. (2017)
https://www.pnas.org/content/114/25/E4905

• Harvard Speaks on Climate Change: James Anderson (2016)
https://vimeo.com/185794598

• Climate Week: Climate Science Breakfast with James Anderson (April 9, 2015)
http://environment.harvard.edu/climate-week-climate-science-breakfast-james-anderson

• 10°C or 18°F warmer by 2021?
https://arctic-news.blogspot.com/2017/04/10c-or-18f-warmer-by-2021.html

• Noctilucent clouds indicate more methane in upper atmosphere
https://arctic-news.blogspot.com/2012/09/noctilucent-clouds-indicate-more-methane-in-upper-atmosphere.html

• Noctilucent clouds: further confirmation of large methane releases
https://methane-hydrates.blogspot.com/2013/12/noctilucent-clouds-further-confirmation-of-large-methane-releases.html

• It could be unbearably hot in many places within a few years time
https://arctic-news.blogspot.com/2016/07/it-could-be-unbearably-hot-in-many-places-within-a-few-years-time.html

• Climate change: effect on sperm could hold key to species extinction, by Kris Sales
https://theconversation.com/climate-change-effect-on-sperm-could-hold-key-to-species-extinction-107375

• Climate change: effect on sperm could hold key to species extinction
https://theconversation.com/climate-change-effect-on-sperm-could-hold-key-to-species-extinction-107375

• UV-B–induced forest sterility: Implications of ozone shield failure in Earth’s largest extinction, by Jeffrey Benca et al. (2018)
http://advances.sciencemag.org/content/4/2/e1700618

• Co-extinctions annihilate planetary life during extreme environmental change, by Giovanni Strona and Corey Bradshaw (2018)
https://www.nature.com/articles/s41598-018-35068-1

• NOAA's Annual Greenhouse Gas Index
https://www.esrl.noaa.gov/gmd/aggi

• NOAA Study Shows Nitrous Oxide Now Top Ozone-Depleting Emission
https://www.esrl.noaa.gov/news/2009/nitrous_oxide_top_ozone_depleting_gas.html

• Earth is on the edge of runaway warming
https://arctic-news.blogspot.com/2013/04/earth-is-on-the-edge-of-runaway-warming.html

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html