National Geographic

The Anthropocene Epoch is an unofficial unit of geologic time, used to describe the most recent period in Earth’s history when human activity started to have a significant impact on the planet’s climate and ecosystems.

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  1. shinichi Post author

    Anthropocene

    https://en.wikipedia.org/wiki/Anthropocene

    The Anthropocene is a proposed geological epoch dating from the commencement of significant human impact on Earth’s geology and ecosystems, including, but not limited to, anthropogenic climate change.

    As of December 2021, neither the International Commission on Stratigraphy (ICS) nor the International Union of Geological Sciences (IUGS) has officially approved the term as a recognised subdivision of geologic time, although the Anthropocene Working Group (AWG) of the Subcommission on Quaternary Stratigraphy (SQS) of the ICS voted in April 2016 to proceed towards a formal golden spike (GSSP) proposal to define the Anthropocene epoch in the geologic time scale (GTS) and presented the recommendation to the International Geological Congress in August 2016. In May 2019, the AWG voted in favour of submitting a formal proposal to the ICS by 2021, locating potential stratigraphic markers to the mid-twentieth century of the common era. This time period coincides with the start of the Great Acceleration, a post-WWII time period during which socioeconomic and Earth system trends increase at a dramatic rate, and the Atomic Age.

    Various start dates for the Anthropocene have been proposed, ranging from the beginning of the Agricultural Revolution 12,000–15,000 years ago, to as recently as the 1960s. The ratification process is still ongoing, and thus a date remains to be decided definitively, but the peak in radionuclides fallout consequential to atomic bomb testing during the 1950s has been more favoured than others, locating a possible beginning of the Anthropocene to the detonation of the first atomic bomb in 1945, or the Partial Nuclear Test Ban Treaty in 1963.

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    An early concept for the Anthropocene was the Noosphere by Vladimir Vernadsky, who in 1938 wrote of “scientific thought as a geological force”. Scientists in the Soviet Union appear to have used the term “anthropocene” as early as the 1960s to refer to the Quaternary, the most recent geological period. Ecologist Eugene F. Stoermer subsequently used “anthropocene” with a different sense in the 1980s and the term was widely popularised in 2000 by atmospheric chemist Paul J. Crutzen, who regards the influence of human behavior on Earth’s atmosphere in recent centuries as so significant as to constitute a new geological epoch.

    In 2008, the Stratigraphy Commission of the Geological Society of London considered a proposal to make the Anthropocene a formal unit of geological epoch divisions. A majority of the commission decided the proposal had merit and should be examined further. Independent working groups of scientists from various geological societies have begun to determine whether the Anthropocene will be formally accepted into the Geological Time Scale.

    The term “anthropocene” is informally used in scientific contexts. The Geological Society of America entitled its 2011 annual meeting: Archean to Anthropocene: The past is the key to the future. The new epoch has no agreed start-date, but one proposal, based on atmospheric evidence, is to fix the start with the Industrial Revolution c. 1780, with the invention of the steam engine. Other scientists link the new term to earlier events, such as the rise of agriculture and the Neolithic Revolution (around 12,000 years BP). Evidence of relative human impact – such as the growing human influence on land use, ecosystems, biodiversity, and species extinction – is substantial; scientists think that human impact has significantly changed (or halted) the growth of biodiversity. Those arguing for earlier dates posit that the proposed Anthropocene may have begun as early as 14,000–15,000 years BP, based on geologic evidence; this has led other scientists to suggest that “the onset of the Anthropocene should be extended back many thousand years”; this would make the Anthropocene essentially synonymous with the current term, Holocene.

    The Trinity test in July 1945 has been proposed as the start of the Anthropocene.
    In January 2015, 26 of the 38 members of the International Anthropocene Working Group published a paper suggesting the Trinity test on 16 July 1945 as the starting point of the proposed new epoch. However, a significant minority supports one of several alternative dates. A March 2015 report suggested either 1610 or 1964 as the beginning of the Anthropocene. Other scholars point to the diachronous character of the physical strata of the Anthropocene, arguing that onset and impact are spread out over time, not reducible to a single instant or date of start.

    A January 2016 report on the climatic, biological, and geochemical signatures of human activity in sediments and ice cores suggested the era since the mid-20th century should be recognised as a geological epoch distinct from the Holocene.

    The Anthropocene Working Group met in Oslo in April 2016 to consolidate evidence supporting the argument for the Anthropocene as a true geologic epoch. Evidence was evaluated and the group voted to recommend “Anthropocene” as the new geological epoch in August 2016. Should the International Commission on Stratigraphy approve the recommendation, the proposal to adopt the term will have to be ratified by the IUGS before its formal adoption as part of the geologic time scale.

    In April 2019, the Anthropocene Working Group announced that they would vote on a formal proposal to the International Commission on Stratigraphy, to continue the process started at the 2016 meeting. In May 2019, 29 members of the 34 person AWG panel voted in favour of an official proposal to be made by 2021. The AWG also voted with 29 votes in favour of a starting date in the mid 20th century. Ten candidate sites for a Global boundary Stratotype Section and Point have been identified, one of which will be chosen to be included in the final proposal. Possible markers include microplastics, heavy metals, or the radioactive nuclei left by tests from thermonuclear weapons.

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  2. shinichi Post author

    人新世

    https://ja.wikipedia.org/wiki/人新世

    人新世(Anthropocene)とは、人類が地球の地質や生態系に与えた影響に注目して提案されている、地質時代における現代を含む区分である。オゾンホールの研究でノーベル化学賞を受賞したパウル・クルッツェンらが2000年にAnthropocene(ギリシャ語に由来し、「人間の新たな時代」の意)を提唱し、国際地質科学連合で2009年に人新世作業部会が設置された。和訳名は人新世のほかに新人世や人類新世がある。人新世の特徴は、地球温暖化などの気候変動、大量絶滅による生物多様性の喪失、人工物質の増大、化石燃料の燃焼や核実験による堆積物の変化などがあり、人類の活動が原因とされる。

    人新世という用語は、科学的な文脈で非公式に使用されており、正式な地質年代とするかについて議論が続いている。人新世の開始年代は様々な提案があり、12,000年前の農耕革命を始まりとするものから、1960年代以降という遅い時期を始まりとする意見まで幅がある。人新世の最も若い年代、特に第二次世界大戦後は社会経済や地球環境の変動が劇的に増加しており、この時期はグレート・アクセラレーション(大加速)と呼ばれる。

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    人新世の概念が根拠とする主な仮説は2つあり、グレート・アクセラレーション(大加速)と、プラネタリー・バウンダリー(地球の限界)である。人類活動が全地球的な環境に与える影響についての仮説は2010年代以降に増え、他に第6の大量絶滅仮説や、フィードバック効果に関するリスク仮説などがある。

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  3. shinichi Post author

    AI/IoT社会における規範問題を考える
    計算社会科学とポスト・ヒューマニティ

    https://www.jstage.jst.go.jp/article/ssi/8/2/8_1/_pdf

     20世紀後半に始まった「情報社会」は,21世紀に入って,より高度なレベルに達した。現代では,単に高機能のコンピュータおよびそのネットワークによって社会が効率化されるというだけでなく,人工知能(AI)技術や,世界のあらゆるモノが常時相互にネット接続されるIoT (Internet of Things)技術が,すでに深くわれわれの生活に浸透している。

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    超情報社会と新たな課題―環境と人口

     ポスト・ヒューマンへと向かう世界は,しかし,現在大きな危機に直面している。Guattari(1989)は「地球という惑星は,いま,激烈な科学技術による変容を経験しているのだが,ちょうどそれに見合うかたちで恐るべきエコロジー的アンバランスの現象が生じている。このエコロジー的アンバランスは,適当な治療がほどこされないならば,ついには地上における生命の存続をおびやかすものとなるだろう。こうした激変と並行して,個人的かつ集団的な人間の生活様式もしだいに悪化の一途をたどっている」と指摘している。

     これに関連して,近年,「人新世(Anthropocene)」という地質学的な概念が注目を集めている。「人新世」とは,人類の活動が地球の地質や生態系に重大な影響を与えるようになった時代を指し,論者によって,起点は農耕の開始期(12000〜15000年前)とも,1960年代ともされる。特に第二次世界大戦以降の急激な変動は「大加速(Great Acceleration)」と呼ばれる。

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