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Thread: Dust Particles Influence On The Weather AND Earth's Climate

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    France Administrator Hervé's Avatar
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    Default Re: Dust Particles Influence On The Weather AND Earth's Climate

    A stalagmite may have solved the mystery of the Akkadian Empire's fall

    IFL Science
    Sat, 29 Dec 2018 04:36 UTC


    © Fredy Thuerig/Shutterstock

    Stalagmites are upward-growing mounds of mineral deposits that have built up due to water dripping onto the floor of a cave, and they reveal quite the history of a land.

    Around 4,200 years ago Mesopotamia's first empire, the Akkadian fell, coinciding with major transformations in Egypt and the Indus Valley, the two other great civilizations of the time. A study of stalagmites in Iran suggests a widespread climatic event may have been responsible for all three.

    Civilizations rise and fall for many reasons, and the causes of the Akkadian Empire's demise remain controversial. The coincidence of timing with far away events has led some historians to propose a climatic cause. The nature, and even existence, of this event has been unclear, however, coming as it did in the middle of the Holocene era of largely stable temperatures, with no known upsurge in volcanic activity or change in solar output.

    However, when a team led by The University of Oxford's Dr Stacy Carolin studied a stalagmite from Gol-e-Zard Cave in Iran's Alborz Mountains formed between 5,200 and 3,700 years ago they saw something certainly happened around the relevant time. The team report in the Proceedings of the National Academy of Sciences there were sharp spikes in the amount of magnesium relative to calcium 4,510 and 4,260 years ago, coinciding with slower growth and changes in the stone's oxygen isotopes. These changes lasted 110 and 290 years, respectively before the stalagmite composition returned to previous levels.


    © Zunkir via Wikimedia Commons CC-by-SA 3.0

    The Akkadian Empire was the first great empire of Mesopotamia, preceding the better known Babylonians and Sumerians. The explanation for its fall has come from mountains on the shores of the distant Caspian Sea.

    The industry and mining of ancient civilizations sometimes left its mark on the planet, but we know of no mechanism by which the Akkadians could have had an impact on such distant caves. Therefore it seems likely that whatever was causing the chemical change brought down the Akkadians, rather than their fall altering the chemistry of distant caves.

    The change in the stalagmite's composition appears to be the result of increased dust falling in the mountains, which in turn seems to be a consequence of drier conditions to the west. Today, dry years in the deserts of Syria and Iraq are associated with increased dust deposition in Tehran, just 50 kilometers (30 miles) from Gol-e-Zard. The slow growth of the stalagmite could be a sign of locally drier conditions as well.

    Sediments from the Red Sea and the Gulf of Oman, among other paleoclimatic proxies, have previously been used to suggest western Asia experienced at least one major dry period around this time, but the dating for these was too imprecise to tie them confidently to the Akkadian collapse. The stalagmites, on the other hand, have an error of just 31 years.

    There is a major debate among historians as to how much climate change has contributed to civilization collapse - one that has become hotter as it becomes more relevant for us. We don't know why Mesopotamia dried out during this period, but it seems it took down one civilization, and severely affected two others.
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  3. Link to Post #42
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    Default Re: Dust Particles Influence On The Weather AND Earth's Climate

    Another contender for the "The Stupid! It Hurts!" award:

    Harvard has formed an advisory board to begin moving forward with their plan to spray particles into the stratosphere to test the geoengineering method of dimming the sun.

    Matt Agorist
    August 3, 2019


    Harvard Scientists Funded by Bill Gates to Begin Spraying Particles Into the Sky In Experiment to Dim the Sun

    No, we are not a satire site. We are not a conspiracy theory site. The information you are about to read is factually accurate and 100% real despite the ostensible ‘skeptics’ who claim otherwise. The controversial subject of geoengineering or weather modification – which was popularized, and oversimplified with the term “chemtrails” – is once again stepping from the shadows and into the light of public scrutiny. And it may soon be a reality as Harvard scientists plan first ever experiment to spray particles in the sky to dim the sun.

    What was once a conspiracy theory is now the subject of congressional debate, peer-reviewed studies, and now a Harvard experiment. Harvard scientists will attempt to replicate the climate-cooling effect of volcanic eruptions with a world-first solar geoengineering experiment. The university announced this month that it has created an external advisory panel to examine the potential ethical, environmental and geopolitical impacts of this geoengineering project, which has been developed by the university’s researchers.

    According to Nature Magazine, Louise Bedsworth, executive director of the California Strategic Growth Council, a state agency that promotes sustainability and economic prosperity, will lead the Harvard advisory panel, the university said on 29 July. The other seven members include Earth-science researchers and specialists in environmental and climate law and policy.

    What was once a conspiracy theory will soon be a reality—any day now.

    Known as the Stratospheric Controlled Perturbation Experiment (SCoPEx), the experiment will spray calcium carbonate particles high above the earth to mimic the effects of volcanic ash blocking out the sun to produce a cooling effect.

    The experiment was announced in Nature magazine last year, who was one of few outlets to look into this unprecedented step toward geoengineering the planet.
    If all goes as planned, the Harvard team will be the first in the world to move solar geoengineering out of the lab and into the stratosphere, with a project called the Stratospheric Controlled Perturbation Experiment (SCoPEx). The first phase — a US$3-million test involving two flights of a steerable balloon 20 kilometres above the southwest United States — could launch as early as the first half of 2019. Once in place, the experiment would release small plumes of calcium carbonate, each of around 100 grams, roughly equivalent to the amount found in an average bottle of off-the-shelf antacid. The balloon would then turn around to observe how the particles disperse.
    Naturally, the experiment is concerning to many people, including environmental groups, who, according to Nature, say such efforts are a dangerous distraction from addressing the only permanent solution to climate change: reducing greenhouse-gas emissions.

    The idea of injecting particles into the atmosphere to cool the earth also seems outright futile considering what scientists are trying to mimic—volcanic eruptions. If we look at the second largest eruption of the 20th century, Mount Pinatubo, which erupted in the Philippines in 1991, it injected 20 million tons of sulfur dioxide aerosols into the stratosphere. Scientists from the USGS estimated that this 20 million tons only lowered the temperature of the planet by about 1°F (0.5°C) and this only lasted a year because the particles eventually fell to back to Earth.

    The Harvard team, led by scientists Frank Keutsch and David Keith, has been working on the SCoPEx project for several years but they haven’t always been in total agreement. In fact, as Nature reported, Keutsch—who is not a climate scientist—previously thought the idea to be “totally insane.” But he’s since changed his mind.

    As Nature reports:
    When he saw Keith talk about the SCoPEx idea at a conference after starting at Harvard in 2015, he says his initial reaction was that the idea was “totally insane”. Then he decided it was time to engage. “I asked myself, an atmospheric chemist, what can I do?” He joined forces with Keith and Anderson, and has since taken the lead on the experimental work.
    Adding to the questionable nature of this experiment is the fact that it is largely funded by none other than Microsoft co-founder, Bill Gates. Gates is no stranger to funding controversial experiments as he’s publicly funded many of them including one that would implant devices into babies to automatically give them vaccines.

    While the Harvard team’s experiment may sound like something out of a dystopian science fiction movie, the reality is that it has long been on the table of governments and think tanks from around the world. In fact, just last November, a study published in Environmental Research Letters, talked about doing the exact same thing—geoengineering and planes spraying particulates into the atmosphere to curb global warming.

    What’s more, that study echoed the sentiments of then-CIA director John Brennan when he addressed the Council on Foreign Relations in 2016, detailing a similar process of spraying chemical particulates in the atmosphere to cool the planet.

    At the meeting, Brennan addressed instability and transnational threats to global security at a meeting with the Council on Foreign Relations. During his long-winded talk of threats to US interests and how the largely CIA-created ISIL threat is impacting the world, Brennan brought up the topic of geoengineering.
    Another example is the array of technologies—often referred to collectively as geoengineering—that potentially could help reverse the warming effects of global climate change. One that has gained my personal attention is stratospheric aerosol injection, or SAI, a method of seeding the stratosphere with particles that can help reflect the sun’s heat, in much the same way that volcanic eruptions do.
    Brennan went on to echo the calls from some scientists who have called for aerial spraying.
    An SAI program could limit global temperature increases, reducing some risks associated with higher temperatures and providing the world economy additional time to transition from fossil fuels. The process is also relatively inexpensive—the National Research Council estimates that a fully deployed SAI program would cost about $10 billion yearly.
    Again, this is not some conspiracy theory. Watch him say all of this in the video below starting at the 12:05 marker.

    The extent to which Brennan talked about stratospheric aerosol injection shows that he and the CIA have likely been considering this for some time.

    Although we are hearing more and more talk about geoengineering, it has been around for a very long time and not just in the realm of conspiracy theories. In fact, scientists have already suggested that it could be going on right now, unintentionally.

    Researchers with the National Oceanic and Atmospheric Administration (NOAA) are suggesting contrails from airplanes may be inadvertently geoengineering the skies.

    Chuck Long is a researcher with the Cooperative Institute for Research in Environmental Sciences (CIRES) at the NOAA Earth System Research Laboratory at the University of Colorado in Boulder. At the American Geophysical Union Fall Meeting in 2015, Long and his team released their paper, “Evidence of Clear-Sky Daylight Whitening: Are we already conducting geoengineering?” The analysis found that vapor from airplanes may be altering the climate through accidental geoengineering.

    To be clear, no one here is claiming to be an expert on climate change or the effects of geoengineering. But one thing is clear and it’s the fact that there is still much to be debated and learned before humans deliberately begin altering Earth’s climate. Aside from doing nothing to curb carbon emissions, if we are so quick to jump on this method, it could set off a chain reaction that could prove to be catastrophic.


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    Default Re: Dust Particles Influence On The Weather AND Earth's Climate

    Plastic particles falling out of sky with snow in the Arctic

    Roger Harrabin BBC
    Wed, 14 Aug 2019 08:29 UTC


    Fragments of plastic are found at high concentrations in Arctic seawater © ALICE TREVAIL

    Even in the Arctic, microscopic particles of plastic are falling out of the sky with snow, a study has found.

    The scientists said they were shocked by the sheer number of particles they found: more than 10,000 of them per litre in the Arctic.

    It means that even there, people are likely to be breathing in microplastics from the air - though the health implications remain unclear.

    The region is often seen as one of the world's last pristine environments.

    A German-Swiss team of researchers has published the work in the journal Science Advances.

    The scientists also found rubber particles and fibres in the snow.

    How did the researchers carry out the study?
    Researchers collected snow samples from the Svalbard islands using a low-tech method - a dessert spoon and a flask.

    In the laboratory at Germany's Alfred Wegener Institute in Bremerhaven they discovered far more contaminating particles than they'd expected.

    Many were so small that it was hard to ascertain where they had come from.


    The researchers collected samples of snow in flasks © ALFRED-WEGENER-INSTITUT / MINE TEKMAN

    The majority appeared to be composed of natural materials like plant cellulose and animal fur. But there were also particles of plastic, along with fragments of rubber tyres, varnish, paint and possibly synthetic fibres.

    The lead scientist, Dr Melanie Bergmann, told BBC News:
    "We expected to find some contamination but to find this many microplastics was a real shock."
    She said:
    "It's readily apparent that the majority of the microplastic in the snow comes from the air."
    Microplastics are defined as those particles below 5mm in size.

    Addressing their potential effects on people, Dr Bergmann explained:
    "We don't know if the plastics will be harmful to human health or not. But we need to take much better care of the way we're treating our environment."
    The scientists also analysed snow from sites in Germany and Switzerland. Samples taken from some areas of Germany showed higher concentrations than in the Arctic.

    How is plastic pollution reaching the Arctic?
    The researchers think microplastics are being blown about by winds and then - through mechanisms which are not fully understood - transported long distances through the atmosphere.

    The particles are then "washed" out of the atmosphere through precipitation, particularly snow.

    A study published in April by a British-French team showed that microplastics were falling from the sky onto the French Pyrenees, another supposedly pristine region.

    Previously, research groups have found plastics in the atmospheric fallout of Dongguan, China, Tehran in Iran, and Paris, France.

    As for where the pollution is coming from, here too there are uncertainties.

    The presence of so many varnish particles in the Arctic was a puzzle.

    The researchers assume that some of the contamination may have come from ships grinding against the ice. But they also speculate that some may have come off wind turbines.

    The fibre fragments may be from people's clothing, although it's not possible to tell at the moment.

    Dr Bergmann explained:
    "We have to ask - do we need so much plastic packaging? Do we need all the polymers in the paints we use? Can we come up with differently designed car tyres? These are important issues."
    Dr Eldbjørg Sofie Heimstad, from the Norwegian Institute for Air Research, Kjeller, who was not involved in the latest study, told me that some of the particle pollution was local and some had drifted from afar.

    She said:
    "We know that most of what we are analysing up there and measuring are long-range transported pollution coming from [Europe], from Asia, coming from all over the world.

    "Some of these chemicals have properties that are a threat for the ecosystem, for living animals."
    What does this mean for the Arctic?
    The results follow on the heels of our exclusive report last year that the highest concentrations of plastic particles in the ocean were to be found in Arctic sea-ice.

    Plastic waste is also drifting for hundreds or even thousands of kilometres to land on remote Arctic beaches.

    It is depressing news for people who have regarded the far north as one of the last pristine environments on Earth.

    At a dog sledding centre near Tromsø in the Norwegian Arctic, one of the staff, Lili, told us:
    "It makes me incredibly sad. We've got plastics in the sea-ice. We've got plastics in the ocean and on the beaches. Now plastic in snow.

    "Up here we see the beauty of it every day, and to see that it's changing so much and being tainted - it hurts."
    ================================================

    Kept out of the picture: Disintegrating satellites on re-entry.
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    Default Re: Dust Particles Influence On The Weather AND Earth's Climate

    'Mystery' eruption that cooled ancient world traced to El Salvador's Ilopango volcano

    Katherine Kornei Science
    Fri, 16 Aug 2019 08:00 UTC


    © NASA/GSFC/METI/ERSDAC/JAROS; U.S./JAPAN ASTER SCIENCE TEAM

    The sixth century was a rough time to be alive: Lower-than-average temperatures in the Northern Hemisphere triggered crop failure, famine, and maybe even the onset of bubonic plague. The ultimate culprit, scientists say, were two back-to-back volcanic eruptions — one in 536 C.E. and another around 540 C.E. The first likely happened in Iceland or North America. But the location of the second one has remained a mystery — until now.

    Researchers studying ancient deposits from El Salvador's Ilopango volcano knew that a massive eruption had taken place there sometime between the third and sixth centuries. That event, dubbed Tierra Blanca Joven (TBJ), or "white young earth," sent a volcanic plume towering nearly 50 kilometers into the atmosphere.

    To better pin down the date of this eruption, the scientists collected slices from three tree trunks embedded in TBJ volcanic ash 25 to 30 kilometers from the present-day lake that covers the caldera (above). The tropical hardwood trees likely died after being engulfed by the searing hot, gale-force winds containing the volcanic gases, ash, and pumice that would have swept outward after the eruption.

    Back in the lab, the researchers estimated the ages of different parts of the slices by counting their rings and using carbon-14 dating. The multiple measurements yielded much more precise dates than could have been gotten from single measurements.

    The three trees all died between 500 and 545 C.E., dates that suggest the TBJ eruption was the mysterious 540 C.E. volcanic event, the researchers report today in Quaternary Science Reviews. In fact, their dating may be even more precise than that: Based on atmospheric circulation patterns, the researchers estimate that the eruption actually occurred in the fall of 539 C.E. That would help explain the era's ongoing global cooling and famine — and could even shed light on a mysterious, temporary break in monument building by the Maya.


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