Presented at
33C3 (2016),
Dec. 28, 2016, 1 p.m.
(30 minutes)
The Anthropocene is widely understood to mean the current <em>"period of Earth's history during which humans have a decisive influence on the state, dynamics and future"</em> of this planet. For several years, scientists in the <a href="http://quaternary.stratigraphy.org/workinggroups/anthropocene/" title="Website of the Working Group on the 'Anthropocene' (AWG)">Working Group on the 'Anthropocene' (AWG)</a> have <a href="https://www2.le.ac.uk/offices/press/press-releases/2016/august/media-note-anthropocene-working-group-awg" title="Media note on AWG recommendations">worked (and voted!)</a> on defining the beginning of the Anthropocene in geochemical terms. The mid-20<sup>th</sup> century provides an obvious geochemical 'timestamp': fallout from <a href="https://media.ccc.de/v/31c3_-_6121_-_en_-_saal_2_-_201412291715_-_what_ever_happened_to_nuclear_weapons_-_michael_buker" title="Michael Büker's 'What Ever Happened to Nuclear Weapons?' talk at 31c3">nuclear weapons detonations</a>. Which other chemicals and timestamps are being considered for marking the Anthropocene's start? How is 'define-by-committee' even working out for <a href="http://www.stratigraphy.org/index.php/ics-chart-timescale" title="International Chronostratigraphic Chart AKA Geological Timescale">geological epochs</a>? This talk boils the scientific background of the Anthropocene debate down for non-stratigraphers.
<p><a href="https://en.wikipedia.org/wiki/Stratigraphy" title="Wikipedia: Stratigraphy">Stratigraphers</a> are geologists, who focus on sediment, rock or ice layers, etc. These 'strata' form by deposition of organic or inorganic material (such as microorganisms or volcanic ash) and provide a records of the history of our planet's surface. Because gas bubbles, isotopes, etc. are captured in the strata, scientists can analyse the geochemistry of the past, date certain events, and more. That kind of data ultimately underlies <a href="https://xkcd.com/1732/" title="xkcd comic 'Earth Temperature Timeline'">xkcd's recent 'Earth Temperature Timeline'</a>. Direct measurements of geochemical signals such as <a href="https://scripps.ucsd.edu/programs/keelingcurve/" title="Keeling curve of CO2 concentrations">atmospheric CO<sub>2</sub> concentration</a> and ocean pH started only in the mid-20<sup>th</sup> century.</p>
<p>Besides the <a href="https://ipcc.ch/" title="Website of the Intergovernmental Panel on Climate Change">Intergovernmental Panel on Climate Change</a>, the AWG is possibly the most diverse scientific committee with most public attention currently. Therefore, defining the Anthropocene is a multi-disciplinary, collaborative scientific effort, as well as an inherently political statement. This talk will explain why.</p>
Presenters:
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KaLeiMai
Studied biochemistry, Arctic ecology and geology in Konstanz and Tromsø. Drifted into tech support & lab automation. Interested in pharmaceutical data integrity, Git, R, and all other sciency and techy thingies. One half of the <a href="http://konscience.de/">KonScience podcast</a>.
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