Accelerating Rise In Greenhouse Gas Levels

Carbon dioxide

The rise in the levels of carbon dioxide (CO₂) in the atmosphere continues to accelerate. Over the past 31 days, CO₂ levels at Mauna Loa, Hawaii, have been above 410 ppm, while on March 3, 2019, some average hourly readings exceeded 415 ppm. The levels recorded in the year up until now weren't expected to occur until April/May 2019, as illustrated by the image below.

How much could carbon dioxide levels grow over the next decade?

An earlier Met Office forecast expects annual average CO₂ levels at Mauna Loa to be 2.75 ppm higher in 2019 than in 2018. Looking at above levels, growth could be even stronger than that.

The image below shows NOAA 1959-2018 CO₂ growth data (black) with above Met Office forecast added for 2019 (brown). The growth figures for 2018 and 2019 are spot on a trend that is added in line with an earlier analysis.

[ from an earlier post ]

Strong CO₂ growth could occur over the next few years, due to releases from increased burning of fossil fuel and biomass, more forest fires and melting permafrost, and the added impact of stronger El Niño events and less uptake of carbon dioxide by oceans and ecosystems. An earlier analysis concludes that CO₂ growth could raise temperatures by 0.5°C or 0.9°F by 2026.

Methane

Levels of methane (CH₄) are also rising at accelerating pace, as illustrated by the image below.

[ from an earlier post ]

Above graph shows July 1983 through October 2018 monthly global methane means at sea level, with added trend. Higher methane means can occur at higher altitudes than at sea level, as illustrated by the image below that shows the highest mean methane levels recorded by the MetOp satellites on March 10 for the years 2013 to 2019 at selected altitudes.

[ click on images to enlarge ]

Global methane levels in March are at a seasonal low. The highest global means occur in September. On September 3, 2018, global 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 MetOp satellites have some difficulty measuring methane at lower altitudes. Above NPP satellite image shows high methane levels across the Arctic Ocean close to sea level, with mean levels of 1842 ppb recorded at 1000 mb, i.e. surface level. This indicates that high methane levels do occur as a result of releases from the Arctic Ocean. The above-mentioned analysis concludes that seafloor methane releases alone could raise the global temperature by 1.1°C or 1.98°F by 2026. Growth in methane releases elsewhere, e.g. due to permafrost melt and forest fires, could further raise methane levels and thus temperatures.

Above image shows that peak methane levels were as high as 2947 ppb on March 7, 2019. The image also shows worryingly high methane levels over Antarctica, as also discussed earlier, in a 2013 post.

Nitrous Oxide

Growth in nitrous oxide (N₂O) is not often discussed, yet it's very important both because of the high global warming potential and long lifetime of N₂O, and because of the ozone depletion it causes in the stratosphere. The image below shows mean levels of N₂O of 320 ppb, with peaks reaching levels as high as 345.2 ppb at 1000 mb (sea level) on March 10, 2019.

Above image also shows high levels of nitrous oxide over the Arctic Ocean. Levels of greenhouse gases in the atmosphere are generally higher in the Arctic than in the rest of the world, which contributes to the accelerating warming of the Arctic.

[ from an earlier post ]

Accelerating Rise In Greenhouse Gas Levels

The image on the right shows that CH₄, CO₂ and N₂O levels in the atmosphere are, respectively, 257%, 146% and 122% their 1750 levels, according to IPCC and WMO data.

In summary, greenhouse gases in the atmosphere are rising at accelerating pace, and this spells bad news, the more so since, next to CH₄, CO₂ and N₂O, there are additional warming elements that can further speed up the temperature rise, such as black carbon, or soot, water vapor, loss of Arctic sea ice, etc.

How much could the global temperature rise? The above-mentioned analysis concludes that a temperature rise of 18°C or 32.4°F could eventuate by 2026, while life on Earth will already have disappeared with a 5°C or 9°F temperature rise.

The situation is dire and calls for comprehensive and effective action as described in the Climate Plan and as also discussed in this recent post.


Links

• CO₂ levels reach another record high
https://arctic-news.blogspot.com/2019/02/co2-levels-reach-another-record-high.html

• As El Niño sets in, will global biodiversity collapse in 2019?
https://arctic-news.blogspot.com/2018/11/as-el-nino-sets-in-will-global-biodiversity-collapse-in-2019.html

• 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

• Methane hydrates (2013)
https://methane-hydrates.blogspot.com/2013/04/methane-hydrates.html

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

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

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