Pleistocene/Holocene (P/H) boundary oceanic Koefels-comet Impact Series Scenario (KISS) of 12.850 yrs BP Global-warming Threshold Triad (GTT): Part V

After 20 years, with 12,854 ± 0.056 ka BP (Wolbach,2018) YDIH, Younger Dryas Impact Hypothesis (Firestone,2007,2009; Moore,2024) confirmed original date of 12.850 cal yrs BP for Continental-Ice, CI-KISS (Bujatti-Narbeshuber,1997b).

270 yrs earlier, Mayan Codex Troano date of Atlantic-Ocean, AO-KISS (13.124 BP), corroborated by Laacher See Eruption (LSE) as impact-volcanism proxy date (Bujatti-Narbeshuber,1997), now 13.160 (Friedrich,2004;Kromer,2004), 13.034 yrs BP (Van Raden,2019), is expanded by Greenland bipolar sulfate (Lin,2022) as Impact-Volcanism-Quadruplet (IVQ). LSE marks start of 5 step-geomagnetism (Dichiara,2023) and (Gravity-Greenhouse Threshold Transition) GTT2-warming “staircase” where LSE-IVQ cooling is overwhelmed by H₂0-gravity-warming (Nikolov,2024,Jucker,2024). GTT2 characterizes Inter-Aleroed-Cold-Period 2 (IACP2) reaching its maximum with Holocene-End-Aleroed-Temperature (HEAT) Melt-Water-Pulse (MWP) 0B with < 6m step in sea level (Bard,2010), the real Younger-Dryas- Onset (YDO) trigger, years later reinforced by CI-KISS (12,854 ka BP), supporting biphasic YD-cooling (Max,2022), then warming MWP1B.

IACP evolves through Atlantic-Ocean (AO-) KISS with Mid-Atlantic Ridge & Plateau Lowering Events (MARPLEs), meso-stratospheric water and gas plume of 25,03 x 10¹⁵  tons (Muck,1976), first into IAPC1-Albedo cooling phase (Repschläger,2023) with bleached magmatic, silico-clastic (Davias and Gilbride,2012) “White Mats” (Bujatti-Narbeshuber,2023) and geomagnetic (Mörner,1977; Chen,2020) Gothenburg-Excursion-Onset (GEO), later LSE, marks, despite 5 LSE-IVQ volcanic cooling episodes, the restart into IAPC2 with the rewarming Gravity-Greenhouse-Threshold GTT-staircase.

Finally the full, both Continental-Ice and Atlantic-Ocean (CIAO-) KISS scenario (Bujatti-Narbeshuber and Hoogewerff,1995), is necessary to explain and predict Pleistocene/Holocene-Catastrophic-Climate-Change (PHCCC).

Research on PHCCC starts from the hypothesis that a Koefels-comet Taurid-fragment impacted into the Ötztal glacier ice near Hohe Geige mountain (3393 m, Tirol, Austria) with Pleistocene/Holocene KISS serving as long sought, necessary trigger factor for the pre-failure weakening of the Koefels crystalline rock, “since there is no other evidence for a pre-existing zone of weakness promoting slope failure” (Zangerl,2021).

Holocene retreat of stabilizing ice, much later, around 9527-9498 cal BP (Nicolussi,2015), lead to the extremely rapid rock slide of Koefels with 3,28 km³ (Brückl,2001).

Koefels-crater is the largest crater in the metamorphic, crystalline area of the Alps. Even seismic fatigue cannot solely explain (Oswald,2021) without the KISS-impact “the particular situation of the Koefels rockslide because it is still unclear why this giant event occurred at this location and within a very strong rock mass” (Zangerl,2021).

Hohe Geige and Koefels crater are furthermore positioned above a unique circular Geomagnetic Anomaly (Ahl, Slapansky,2003) evident in the aeromagnetic map of Austria (Seiberl,1991), suggested  as impact magnetism based on growing evidence for a global CIAO-KISS event (Bujatti-Narbeshuber,1997a).  

Hohe Geige and Koefels extend northward into a sector, widening from 12 to 17 km, 50 km long, that contains the largest concentration of rock slides (12) in the Alps (Tollmann,1992; Abele,1974). This is explained by both seismicity or an ejecta curtain from an oblique KISS-impact and already led to solving the Carolina Bays enigma as late Pleistocene, 12.850 cal yrs BP, “paleoseismic, impact-seismic, liquefaction features” (Bujatti-Narbeshuber, 1997b).

Koefels-comet Taurid-fragments with an oblique Ice-impact into the Ötztal glacier low-impedance ice-layer “guiding the pressure wave horizontally thus absorbing up to 70% of the impact energy would significantly reduce both the peak pressures at depth along with their expressions in the rock record” (Stickle,Schultz,2012,2013; French, Koeberl,2010).