When Will We Die?

A rise of more than 5°C could happen within a decade, possibly by 2026. Humans will likely go extinct with a 3°C rise and most life on Earth will disappear with a 5°C rise. In the light of this, we should act with integrity.

When will we die?

The outlook for people living now is that they will die before the end of the century. After all, even in more developed regions, people statistically die at an age below 75 years, as the image on the right illustrates.

The image calls up questions regarding possible shortening of life expectancy due to global heating.

A 2018 study by Strona & Bradshaw indicates that most life on Earth will disappear with a 5°C rise (see box on the right).

The first question therefore is whether and how fast such a rise could eventuate.

Furthermore, global heating projections for the year 2100 may seem rather irrelevant to many people, as they do not expect to be alive by the year 2100.

A second question therefore is what makes most sense, focusing on the year 2100, or on how much temperatures could rise over the next decade.

Clouds tipping point

A recent study points at a tipping point of 1,200 ppm CO₂e when marine stratus clouds start to disappear, resulting in an additional global heating of eight degrees Celsius (8°C or 14.4°F).

In other words, such a rise from clouds feedback would clearly suffice to cause extinction of most life on Earth.

Could this tipping point be crossed soon?

At its high-end, the A1F1 scenario used by the IPCC reaches a CO₂e level of 1550 ppm by the year 2100 (see screenshot below).

As discussed, the year 2100 is rather distant. The question is, could this 1,200 ppm CO₂e tipping point be crossed earlier, say, within one decade?

On May 15, 2019, scripps.ucsd.edu recorded a carbon dioxide level of 415.7 ppm at Mauna Loa, Hawaii. NOAA recorded a methane level of 1.867 ppm for December 2018. As shown at the FAQ page, methane is 150 times as potent as a greenhouse gas over the next ten years compared to carbon dioxide. Accordingly, this 1.867 ppm of methane causes global heating of 280.05 ppm CO₂e.

Seafloor methane

Imagine a burst of methane erupting from the seafloor of the Arctic Ocean that would add an amount of methane to the atmosphere equal to twice the methane that is already there. Twice the 1.867 ppm of methane is 3.734 ppm, which at 150 times the potency of carbon dioxide translates into a CO₂e of 560.1 ppm.

Adding this to the current levels of carbon dioxide and methane results in a level of 1255.85 ppm CO₂e, well exceeding the 1,200 ppm CO₂e tipping point and thus triggering the extra 8°C rise.

Above image was created with content from a recent paper by Natalia Shakhova et al. It shows that the outlook is much more grim than many people realize.

Above image illustrates the danger, as an ominous sign of what's on the way. Methane levels as high as 2.975 ppm were recorded on June 11, 2019, at 469 mb. A peak this high is likely to have originated from the seafloor.

Above image shows a solid-colored magenta area over the ESAS that afternoon, further indicating that large amounts of methane did erupt earlier that day from destabilizing sediments in the ESAS.

Koalas declared functionally extinct

The Australian Koala Foundation has declared Koalas "functionally extinct". While there still are some 80,000 Koalas left, it is unlikely that Koalas will be able to escape full extinction for long.

Climate change-driven droughts and heat waves are causing dehydration and heat stress, leading to organ failure and premature death.

A rapid temperature rise could make virtually all species on Earth go extinct. As the above-mentioned study points out, even the most robust lifeforms on Earth will likely disappear with a 5°C rise, as species on which they depend will die.

Near Term Human Extinction

For mammals, which depend on a lot of other species, extinction is likely to come earlier.  When looking at near-term human extinction, a 3°C rise from preindustrial will likely suffice to cause extinction.

In 2019, the global temperature could already be 1.85°C above preindustrial and a rapid temperature rise could take place over the next few years.

A lot of good action is possible, as described in the Climate Plan, which offers the greatest amount of flexibility in local implementation, within the constraints of the need to act on climate change as acknowledged, e.g. at the Paris Agreement.

Nonetheless, humans likely are already functionally extinct, as is most life on Earth. This may come as a surprise to many people, but that shouldn't stop people from doing the right thing.

The above image reflects the joint CO₂e impact of carbon dioxide and methane. In addition, there is the impact of further greenhouse gases, such as nitrous oxide and CFCs, as described in a recent post. There are more warming elements, such as albedo loss associated with the decline of the snow and ice cover. These warming elements could jointly push up the temperature rise to some 10°C above preindustrial, while the clouds feedback could add a further 8°C on top of that.

Sulfates do have a cooling effect, but this effect may fall away as society grinds to a halt and stops co-emitting sulfates alongside other emissions in the process of burning fuel, as Guy McPherson has pointed out repeatedly, e.g. in this recent post.

In the video below, recorded at the University of Alaska-Fairbanks on 4 April 2019, Guy McPherson explains how loss of habitat can lead to extinction of species and how global heating can lead to extinction of virtually all life on Earth.

Added below is a video edited by Tim Bob of Guy McPherson talking in Juneau, Alaska, in April, 2019.

In the video below, Examples of Rapid Extinction, Guy McPherson gives examples of species that went extinct rapidly in the past, warning that to rule out rapid extinction of humans would be foolish.

Links

• United Nations, world population prospects, 2017, Life expectancy
https://www.un.org/en/development/desa/population/publications/pdf/popfacts/PopFacts_2017-9.pdf
https://www.un.org/development/desa/publications/world-population-prospects-the-2017-revision.html

• Intergovernmental Panel on Climate Change (IPCC) AR4 (2007), Working Group I: The Physical Science Basis
https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/spmsspm-projections-of.html

• 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

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

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

• Possible climate transitions from breakup of stratocumulus decks under greenhouse warming, by Tapio Schneider et al.
https://www.nature.com/articles/s41561-019-0310-1

• FAQ #13: What is the global warming potential of methane?
https://arctic-news.blogspot.com/p/faq.html#13

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

• Methane, measured by the Infrared Atmospheric Sounding Interferometer (IASI) residing on the MetOp polar orbiting satellites
https://www.ospo.noaa.gov/Products/atmosphere/soundings/iasi

• 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

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

• Stronger Extinction Alert
https://arctic-news.blogspot.com/2019/03/stronger-extinction-alert.html

• Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf, by Natalia Shakhova, Igor Semiletov and Evgeny Chuvilin
https://www.mdpi.com/2076-3263/9/6/251

• Guy McPherson at the University of Alaska-Fairbanks, April 2019
https://guymcpherson.com/2019/04/the-first-of-two-presentations-at-the-university-of-alaska-fairbanks/

• Guy McPherson in Juneau, Alaska, April 2019
https://guymcpherson.com/2019/05/presentation-in-juneau-alaska

• Seven Distinct Paths to Loss of Habitat for Humans, by Guy McPherson
https://weeklyhubris.com/seven-distinct-paths-to-loss-of-habitat-for-humans


Koalas

• Koala habitat 1788 versus 2018
From: savethekoala.com
https://www.savethekoala.com/our-work/act-or-axe

• A report claims koalas are ‘functionally extinct’ – but what does that mean?
https://theconversation.com/a-report-claims-koalas-are-functionally-extinct-but-what-does-that-mean-116665

• Australian Koala Foundation calls on the new Prime Minister to protect the Koala
https://www.savethekoala.com/sites/savethekoala.com/files/uploads/AKF_press_release_10_may_2019.pdf

• Koalas become 'Functionally Extinct' in Australia with just 80,000 left
https://www.ecowatch.com/koalas-functionally-extinct-australia-2637183484.html

• Koalas declared “functionally extinct”
https://inhabitat.com/koalas-declared-functionally-extinct

• Why the Heck Do So Many Koalas Have Chlamydia?
https://www.livescience.com/62517-how-koalas-get-chlamydia.html

Near-Term Human Extinction

Global Warming and Feedbacks

Is there a mechanism that could make humanity go extinct in the not-too-distant future, i.e. within a handful of decades?

Most people will be aware that emissions due to human activity are causing global warming, as illustrated by the arrow marked 1 in the image on the left. Global warming can cause changes to the land, to vegetation and to the weather. This can result in wildfires that can in turn cause emissions, thus closing the loop and forming a self-reinforcing cycle that progressively makes things worse.

Furthermore, less forests and soil carbon also constitute a decrease in carbon sinks, resulting in carbon that would otherwise have been absorbed by such sinks to instead remain in the atmosphere, thus causing more global warming, as illustrated by the additional downward arrow in the image on the right. In conclusion, there are a number of processes at work that can all reinforce the impact of global warming.

Emissions can also contribute more directly to land degradation, to changes in vegetation and to more extreme weather, as indicated by the additional arrow pointing upward in the image on the right. A recent study by Yuan Wang et al. found that aerosols formed by human activities from fast-growing Asian economies can cause more extreme weather, making storms along the Pacific storm track deeper, stronger, and more intense, while increasing precipitation and poleward heat transport.

Accelerated Warming in the Arctic

Similar developments appear to be taking place over the North Atlantic. Huge pollution clouds from North America are moving over the North Atlantic as the Earth spins. In addition, the Gulf Stream carries ever warmer water into the Arctic Ocean. As the image below shows, sea surface temperature anomalies at the highest end of the scale (8 degrees Celsius) are visible off the coast of North America, streching out all the way into the Arctic Ocean.

As said, feedbacks as are making the situation progressively worse. Feedback loops are causing warming in the Arctic to accelerate. Warming in the Arctic is accelerating with the demise of the snow and ice cover in the Arctic, and this is only feedback #1 out out many feedbacks that are hitting the Arctic, as described in an earlier post. As the temperature difference between the equator and the Arctic decreases, the Jet Stream is changing, making it easier for cold air to move out of the Arctic and for warm air from lower latitudes to move in (feedback #10).

Abrupt Climate Change leading to Extinction at Massive Scale

The danger is that, as temperatures over the Arctic Ocean warm up further and as the Gulf Stream carries ever warmer water into the Arctic Ocean, large quantitities of methane will erupt abruptly from the seafloor of the Arctic Ocean, adding a third kind of warming, runaway warming resulting in abrupt climate change, and leading to mass death, destruction and extiction of species including humans.

Persistence of such a progression makes it inevitable that the rest of Earth will follow the huge temperature rises in the Arctic. Massive wildfires will first ignite across higher latitudes, adding further greenhouse gas emissions and causing large deposits of soot on the remaining snow and ice on Earth, with a huge veil of methane eventually spreading around the globe. The poster below, from an earlier post, illustrates the danger.

[ click on image to enlarge - note that this is a 1.8 MB file that may take some time to fully load ]

Views by Contributors

How likely is it that the above mechanism will cause human extinction within the next few decades? What views do the various contributors to the Arctic-news blog have on this?

Guy McPherson has long argued that, given the strengths of the combined feedbacks and given the lack of political will to take action, near-term human extinction is virtually inevitable.

In the video below, Paul Beckwith responds to the question: Can climate change cause human extinction?

Further contributors are invited to have their views added to this post as well. While many contributors may largely share Paul Beckwith's comments, it's important to highlight that contributors each have their own views, and this extends to their preference for a specific plan of action.

Geo-engineering

One of the more controversial issues is the use of geo-engineering. Guy McPherson doesn't believe geo-engineering will be successful. In the video below, Paul Beckwith gives his (more positive) views on this.

I must admit that the lack of political will to act is rather depressing, especially given the huge challenges ahead. So, I can understand that this can make some of us pessimistic at times. Nonetheless, I am an optimist at heart and I am convinced that we can get it right by giving more support to a Climate Plan that is both comprehensive and effective, as discussed at ClimatePlan.blogspot.com