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The Anthropocene Epoch

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    The Anthropocene Epoch

    So, looks like we're at the beginning of a new epoch. Sadly there isn't much in the way of encouragement to put in here, but by way of background for those who aren't sure what the concept means, here's an article to put it into context.

    The Anthropocene epoch: scientists declare dawn of human-influenced age


    Humanity’s impact on the Earth is now so profound that a new geological epoch – the Anthropocene – needs to be declared, according to an official expert group who presented the recommendation to the International Geological Congress in Cape Town on Monday.
    The new epoch should begin about 1950, the experts said, and was likely to be defined by the radioactive elements dispersed across the planet by nuclear bomb tests, although an array of other signals, including plastic pollution, soot from power stations, concrete, and even the bones left by the global proliferation of the domestic chicken were now under consideration.
    The current epoch, the Holocene, is the 12,000 years of stable climate since the last ice age during which all human civilisation developed. But the striking acceleration since the mid-20th century of carbon dioxide emissions and sea level rise, the global mass extinction of species, and the transformation of land by deforestation and development mark the end of that slice of geological time, the experts argue. The Earth is so profoundly changed that the Holocene must give way to the Anthropocene.
    “The significance of the Anthropocene is that it sets a different trajectory for the Earth system, of which we of course are part,” said Prof Jan Zalasiewicz, a geologist at the University of Leicester and chair of the Working Group on the Anthropocene (WGA), which started work in 2009.
    “If our recommendation is accepted, the Anthropocene will have started just a little before I was born,” he said. “We have lived most of our lives in something called the Anthropocene and are just realising the scale and permanence of the change.”
    Prof Colin Waters, principal geologist at the British Geological Survey and WGA secretary, said: “Being able to pinpoint an interval of time is saying something about how we have had an incredible impact on the environment of our planet. The concept of the Anthropocene manages to pull all these ideas of environmental change together.”

    Prof Chris Rapley, a climate scientist at University College London and former director of the Science Museum in London said: “The Anthropocene marks a new period in which our collective activities dominate the planetary machinery.
    “Since the planet is our life support system – we are essentially the crew of a largish spaceship – interference with its functioning at this level and on this scale is highly significant. If you or I were crew on a smaller spacecraft, it would be unthinkable to interfere with the systems that provide us with air, water, fodder and climate control. But the shift into the Anthropocene tells us that we are playing with fire, a potentially reckless mode of behaviour which we are likely to come to regret unless we get a grip on the situation.” Rapley is not part of the WGA.
    Martin Rees, the astronomer royal and former president of the Royal Society, said that the dawn of the Anthropocene was a significant moment. “The darkest prognosis for the next millennium is that bio, cyber or environmental catastrophes could foreclose humanity’s immense potential, leaving a depleted biosphere,” he said.

    But Lord Rees added that there is also cause for optimism. “Human societies could navigate these threats, achieve a sustainable future, and inaugurate eras of post-human evolution even more marvellous than what’s led to us. The dawn of the Anthropocene epoch would then mark a one-off transformation from a natural world to one where humans jumpstart the transition to electronic (and potentially immortal) entities, that transcend our limitations and eventually spread their influence far beyond the Earth.”
    The evidence of humanity’s impact on the planet is overwhelming, but the changes are very recent in geological terms, where an epoch usually spans tens of millions of years. “One criticism of the Anthropocene as geology is that it is very short,” said Zalasiewicz. “Our response is that many of the changes are irreversible.”

    To define a new geological epoch, a signal must be found that occurs globally and will be incorporated into deposits in the future geological record. For example, the extinction of the dinosaurs 66m years ago at the end of the Cretaceous epoch is defined by a “golden spike” in sediments around the world of the metal iridium, which was dispersed from the meteorite that collided with Earth to end the dinosaur age.
    For the Anthropocene, the best candidate for such a golden spike are radioactive elements from nuclear bomb tests, which were blown into the stratosphere before settling down to Earth. “The radionuclides are probably the sharpest – they really come on with a bang,” said Zalasiewicz. “But we are spoiled for choice. There are so many signals.”
    Other spikes being considered as evidence of the onset of the Anthropocene include the tough, unburned carbon spheres emitted by power stations. “The Earth has been smoked, with signals very clearly around the world in the mid-20th century,” said Zalasiewicz.

    Other candidates include plastic pollution, aluminium and concrete particles, and high levels of nitrogen and phosphate in soils, derived from artificial fertilisers. Although the world is currently seeing only the sixth mass extinction of species in the 700m-year history of complex life on Earth, this is unlikely to provide a useful golden spike as the animals are by definition very rare and rarely dispersed worldwide.
    In contrast, some species have with human help spread rapidly across the world. The domestic chicken is a serious contender to be a fossil that defines the Anthropocene for future geologists. “Since the mid-20th century, it has become the world’s most common bird. It has been fossilised in thousands of landfill sites and on street corners around the world,” said Zalasiewicz. “It is is also a much bigger bird with a different skeleton than its prewar ancestor.”
    The 35 scientists on the WGA – who voted 30 to three in favour of formally designating the Anthropocene, with two abstentions – will now spend the next two to three years determining which signals are the strongest and sharpest. Crucially, they must also decide a location which will define the start of the Anthropocene. Geological divisions are not defined by dates but by a specific boundary between layers of rock or, in the case of the Holocene, a boundary between two ice layers in a core taken from Greenland and now stored in Denmark.

    The scientists are focusing on sites where annual layers are formed and are investigating mud sediments off the coast of Santa Barbara in California and the Ernesto cave in northern Italy, where stalactites and stalagmites accrete annual rings. Lake sediments, ice cores from Antarctica, corals, tree rings and even layers of rubbish in landfill sites are also being considered.
    Once the data has been assembled, it will be formally submitted to the stratigraphic authorities and the Anthropocene could be officially adopted within a few years. “If we were very lucky and someone came forward with, say, a core from a classic example of laminated sediments in a deep marine environment, I think three years is possibly viable,” said Zalasiewicz.

    This would be lightning speed for such a geological decision, which in the past would have taken decades and even centuries to make. The term Anthropocene was coined only in 2000, by the Nobel prize-winning scientist Paul Crutzen, who believes the name change is overdue. He said in 2011: “This name change stresses the enormity of humanity’s responsibility as stewards of the Earth.” Crutzen also identified in 2007 what he called the “great acceleration” of human impacts on the planet from the mid-20th century.
    Despite the WGA’s expert recommendation, the declaration of the Anthropocene is not yet a foregone conclusion. “Our stratigraphic colleagues are very protective of the geological time scale. They see it very rightly as the backbone of geology and they do not amend it lightly,” said Zalasiewicz. “But I think we can prepare a pretty good case.”
    Rapley also said there was a strong case: “It is highly appropriate that geologists should pay formal attention to a change in the signal within sedimentary rock layers that will be clearly apparent to future generations of geologists for as long as they exist. The ‘great acceleration’ constitutes a strong, detectable and incontrovertible signal.”

    (part 1 or 2)
    Last edited by mr chips; 19-September-2016, 22:47.
    Tis but a scratch.

    #2
    (part 2 of 2)

    Evidence of the Anthropocene


    Human activity has:
    • Pushed extinction rates of animals and plants far above the long-term average. The Earth is on course to see 75% of species become extinct in the next few centuries if current trends continue.


    • Put so much plastic in our waterways and oceans that microplastic particles are now virtually ubiquitous, and plastics will likely leave identifiable fossil records for future generations to discover.

    • Doubled the nitrogen and phosphorous in our soils in the past century with fertiliser use. This is likely to be the largest impact on the nitrogen cycle in 2.5bn years.

    • Left a permanent layer of airborne particulates in sediment and glacial ice such as black carbon from fossil fuel burning.
    Tis but a scratch.

    Comment


      #3
      This was the article that prompted me to post the thread ...

      An American tragedy: why are millions of trees dying across the country?

      JB Friday hacked at a rain-sodden tree with a small axe, splitting open a part of the trunk. The wood was riven with dark stripes, signs of a mysterious disease that has ravaged the US’s only rainforests – and just one of the plagues that are devastating American forests across the west.

      Friday, a forest ecologist at the University of Hawaii, started getting calls from concerned landowners in Puna, which is on the eastern tip of Hawaii’s big island, in 2010. Their seemingly ubiquitous ohi’a trees were dying at an astonishing rate. The leaves would turn yellow, then brown, over just a few weeks – a startling change for an evergreen tree.
      “It was like popcorn – pop, pop, pop, pop, one tree after another,” Friday said. “At first people were shocked, now they are resigned.
      “It’s heartbreaking. This is the biggest threat to our native forests that any of us have seen. If this spreads across the whole island, it could collapse the whole native ecosystem.”
      Almost six years later and nearly 50,000 acres of native forest on the big island are infected with rapid ohi’a death disease. Rumors abound as to its origin: did it emerge from Hawaii’s steaming volcanoes? A strange new insect? Scientists still aren’t sure of where it came from or how to treat it.

      Lisa Keith, researcher in plant pathology at the US Department of Agriculture, said that when she analyzed the disease “right away Dutch elm disease popped into my head”. But this was unlike anything she, or anyone else, had ever dealt with.
      “I’m not sure if there’s been anything else like this in the world,” she said. “The potential is there for major devastation.” Keith said the disease hadn’t yet spread to crops, like coffee, but it threatens a whole family of metrosideros trees and shrubs found mainly in the Pacific.
      But the plight of the ohi’a is not unique - it’s part of a quiet crisis playing out in forests across America. Drought, disease, insects and wildfire are chewing up tens of millions of trees at an incredible pace, much of it driven by climate change.
      ‘Mountainsides dying’

      Forestry officials and scientists are increasingly alarmed, and say the essential role of trees – providing clean water, locking up carbon and sheltering whole ecosystems – is being undermined on a grand scale.
      California and mountain states have suffered particularly big die-offs in recent years, with 66m trees killed in the Sierra Nevada alone since 2010, according to the Forestry Service.
      In northern California, an invasive pathogen called Sudden Oak Death is infecting hundreds of different plants, from redwoods and ferns to backyard oaks and bay laurels. The disease is distantly related to the cause of the 19th-century Irish potato famine, and appears to have arrived with two “Typhoid Marys”, rhododendrons and bay laurels, said Dr David Rizzo, of the University of California, Davis.

      “We’re talking millions of trees killed, whole mountain sides dying,” Rizzo said.
      Despite its name, the pathogen slowly saps the life from oaks over the course of two to five years, turning them sickly brown. The disease spreads mostly through water, like rain splashing off an infected leaf on to a healthy neighbor. Rizzo said wind-driven rain could carry it miles at a time, and that it already ranged from the Oregon border down through the forests of Big Sur.


      The pestilence appears to have arrived in the US through nursery plants in the 1980s, said Matteo Garbelotto, a professor at the University of California, Berkeley, who researches the genetics of the disease and trees that resist it. Garbelotto said researchers have found three distinct “subspecies” of the pathogen in the US – only one of which has escaped into the wild.
      “There’s a bit of concern here that maybe we’re not doing enough to prevent introduction of other two lineages,” he said. Authorities have quarantined 15 counties to keep infected plants from leaving, but Garbelotto fears that authorities lack the resources to do more.
      Native American tribes are helping Rizzo’s research near Oregon, and Garbelotto’s team developed a mobile app that users can direct at a given tree to determine its risk for disease, and what they can do to protect it.
      “It’s a little bit like talking about mosquito abatement and malaria,” Garbelotto said of efforts to protect some trees by isolating them. “You try to reduce the number of vectors, eliminate immediate neighbors, a bit like putting a mosquito net around the tree.”
      ‘Insect eruptions’

      Five years of drought in the west have not only starved trees of water but weakened their defenses and created conditions for “insect eruptions” across the US, said Diana Six, an entomologist at the University of Montana. Bark beetles and mountain pine beetles, usually held in check by wet winters, now have more time to breed and roam. The latter have already expanded their range from British Columbia across the Rockies, to the Yukon border and eastward, into jack pine forests that have never seen the bug.
      The outbreak is “something like 10 times bigger than normal, I would argue a lot more than that,” Six said. “Basically a native insect is acting outside of the norm, because of climate change, and become an exotic in forests it’s never been before. We haven’t seen very good outcomes of exotics moving into native forests.”
      Boosted by climate change, various beetles and the fungi they carry have already wiped out millions of acres of trees, and Six and Rizzo both warned of cascading effects. In the redwoods, Rizzo said, the loss of tanoaks and their relatives would strip away nut-producing species, leaving birds and mammals that rely on them without food. The loss of mountain pines, Six said, threatens grizzly bears and the critical snowpack that supplies water to life below.

      “There’s virtually nothing you can do to stop the beetles, either, unless they’ve killed everything and run out of food,” Six said. “Or unless the climate cools, and I don’t think anyones expecting that anytime soon.”
      In Hawaii, warming temperatures have helped spread four types of beetles that bore into ohi’a bark to feed. The beetles carry disease spore on their wings, in their guts and in the sawdust of burrows, spreading it from tree to tree.

      The beetles are part of scolylinae, a “very destructive family” that is also decimating trees in California, according to Curtis Ewing, an entomologist at the University of Hawaii.
      “They are exploding around the world due to global warming,” he said. They appear unstoppable: spraying each tree with insecticide would be time-consuming and made futile by rain, and pheromone-laced traps also appear ineffective. The university’s arboretum has started collecting ohi’a seeds in the face of a doomsday scenario that was recently unimaginable for such a common tree.
      ‘An ecological emergency’

      Scientists in Keith’s lab have made some progress, finding that the fungal disease was part of the common ceratocystis family. It was probably imported to Hawaii by an ornamental plant, but a global DNA database drew a blank; this was an entirely new strain.

      “I would’ve thought that with the extensive information there, there would’ve been a match,” Keith said. “It’s a worry.”
      The spores look golden under the microscope and give off a fruity smell. Once they grip a tree the fungus clogs up the vascular system that trees use to draw water upwards. Leaves die, then the tree itself.

      If you slice right through an infected tree, you find a starburst of dark fungus at the core. “It’s like someone’s arteries filling up with plaque and then they keel over,” Friday said.
      While research continues for a treatment, scientists’ current priority is containment. Movement of ohi’a between islands is prohibited, but with an uncertain source, there’s little else to do other than cut down infected trees and burn them.
      “This is an ecological emergency,” said Hawaii senator Brian Schatz. “It requires everyone working together to save Hawaii island’s native forests.”
      In western valleys of dead trees, a few still stand unharmed. Six said genetic research has begun to try to understand why some survive the swarms of millions of insects. “The only thing that’s really going to help our forests move into the future with climate change is adaptation,” she said. “Forests need to actually adapt with genetic change.”
      In a few decades, Americans might not even recognize forests they see, Rizzo said. When his grandfather grew up near Philadelphia, he said, gigantic chestnut trees towered over eastern forests.
      “When I show people photos they think they’re redwoods,” Rizzo said. When he hiked the Appalachian trial in the 1980s he found tiny sprouts of chestnuts, three-inches wide, stunted by an invasive blight that had wiped out the old giants.
      “It changed chestnut forests to oak and hickory forests,” he said. “We know we can’t get rid of some of these blights. We may have to learn to live with them.”
      Tis but a scratch.

      Comment


        #4
        Also, to put the most recent few years into context, an enormographic from the excellent XKCD ...
        (click on link if you can't see it here)
        Tis but a scratch.

        Comment


          #5
          I misread the thread title and thought you were on about the new film 'Anthropoid'.

          Interesting stuff this.
          If your religion is worth killing for, please start with yourself.

          Comment


            #6
            Thread title amended slightly to aid clarity. :smile2:
            Tis but a scratch.

            Comment


              #7
              History is going to have a special place reserved for climate change deniers. Somewhere around the same place as the guy who chopped down the last tree on Easter Island.
              "We will not walk in fear, one of another. We will not be driven into an age of unreason if we dig deep into our history and remember we are not descended from fearful men" Edward R Murrow

              "Little by little, we have been brought into the present condition in which we are able neither to tolerate the evils from which we suffer, nor the remedies we need to cure them." - Livy


              "I think that progress has been made by two flames that have always been burning in the human heart. The flame of anger against injustice and the flame of hope that you can build a better world" - Tony Benn

              Comment


                #8
                The Anthropocene Epoch

                Originally posted by Balla Boy View Post
                History is going to have a special place reserved for climate change deniers. Somewhere around the same place as the guy who chopped down the last tree on Easter Island.
                The climate has always been changing, the difference now is that the world is so massively over populated with human beings that we are unable to adapt to the changes that are ensuing. I still believe there will be a hideous pandemic, possibly exacerbated by the ever greater density in which mankind will be forced to live because of the symptoms of this change in the climate, that will reduce the human population to more sustainable levels. Nature finds a way.


                Sent from my iPhone using Tapatalk
                Last edited by the plastic paddy; 20-September-2016, 06:59.

                Comment


                  #9
                  Very interesting.

                  Shocking prediction about 75% of the earth's species becoming extinct.

                  Comment


                    #10
                    Originally posted by the plastic paddy View Post
                    The climate has always been changing, the difference now is that the world is so massively over populated with human beings that we are unable to adapt to the changes that are ensuing. I still believe there will be a hideous pandemic, possibly exacerbated by the ever greater density in which mankind will be forced to live because of the symptoms of this change in the climate, that will reduce the human population to more sustainable levels. Nature finds a way.


                    Sent from my iPhone using Tapatalk
                    See the infographic above for why it's vastly different this time. The bit of info near the 16000 BC timeline about margins of error is interesting.
                    Tis but a scratch.

                    Comment


                      #11
                      Click image for larger version

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                      "Some people don't know their easy lives... I wouldn't be so ungrateful" - Fiacre Ryan - #AutismAndMe

                      Comment


                        #12
                        The Anthropocene Epoch

                        Originally posted by mr chips View Post
                        See the infographic above for why it's vastly different this time. The bit of info near the 16000 BC timeline about margins of error is interesting.
                        But it is all down to a massive population explosion in the last hundred (edit 200)years. There are too many people on earth to be sustainably resourced. We are rapidly eating into our nest egg, rather than sustainably living off of it.


                        Sent from my iPhone using Tapatalk
                        Last edited by the plastic paddy; 20-September-2016, 09:44.

                        Comment


                          #13
                          Originally posted by the plastic paddy View Post
                          But it is all down to a massive population explosion in the last hundred (edit 200)years. There are too many people on earth to be sustainably resourced. We are rapidly eating into our nest egg, rather than sustainably living off of it.


                          Sent from my iPhone using Tapatalk
                          So many planets to choose from when this one is fecked...
                          ​​​​​​#GiveLeinsterTheHCupNow

                          Originally Posted by mr chips
                          AG gets the responses he does because he is a journalist..

                          Comment


                            #14
                            I'm with The Healy raes on this...it's just easier and there is less reading.
                            Tic-Toc. POC and DOC. Stop the clock.

                            Comment


                              #15
                              Originally posted by AdolphusGrigson View Post
                              So many planets to choose from when this one is fecked...
                              Quite right. Simplicity is the key. Down with experts. Trump for president.
                              ​​​​​​#GiveLeinsterTheHCupNow

                              Originally Posted by mr chips
                              AG gets the responses he does because he is a journalist..

                              Comment

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