Heinrich event facts for kids
Heinrich events occurred during the coldest point of Bond Cycles in which many icebergs were discharged into the North Atlantic and melted.
Evidence for this can be found in the north Atlantic sediment cores which show poorly sorted, angular and contain rocks. These were originally in the icebergs but dropped to the bottom of the ocean when the icebergs melted.
Heinrich events are a possible trigger to the onset of mini ice ages which follow a long period of thaw. An example might be the Younger Dryas, a brief cold period from about 12.8 thousand years ago to about 11.5 thousand years ago.
The Younger Dryas stadial is thought to have been caused by the collapse of the North American ice sheets, although rival theories have been proposed.
Images for kids
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The H1 Heinrich event occurred in the Pleistocene, around 16,000 years ago. Evolution of temperature in the Post-Glacial period since the Last Glacial Period, according to Greenland ice cores.
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Chronology of climatic events of importance for the Last Glacial Period (~last 120,000 years) as recorded in polar ice cores, and approximate relative position of Heinrich events, initially recorded in marine sediment cores from the North Atlantic Ocean. Light violet line: δ18O from the NGRIP ice core (Greenland), permil (NGRIP members, 2004). Orange dots: temperature reconstruction for the NGRIP drilling site (Kindler et al., 2014). Dark violet line: δ18O from the EDML ice core (Antarctica), permil (EPICA community members, 2006). Grey areas: major Heinrich events of mostly Laurentide origine (H1, H2, H4, H5). Grey hatch: major Heinrich events of mostly European origine (H3, H6). Light grey hatch and numbers C-14 to C-25: minor IRD layers registered in North Atlantic marine sediment cores (Chapman et al., 1999). HS-1 to HS-10: Heinrich Stadial (HS, Heinrich, 1988; Rasmussen et al., 2003; Rashid et al., 2003). GS-2 to GS-24: Greenland Stadial (GS, Rasmussen et al., 2014). AIM-1 to AIM-24: Antarctic Isotope Maximum (AIM, EPICA community members, 2006). Antarctica and Greenland ice core records are shown on their common timescale AICC2012 (Bazin et al., 2013; Veres et al., 2013).
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As well as indicating oceanic productivity, foramanifera tests also provide valuable isotopic data
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The lithic proportion of sediments deposited during H3 and H6 is substantially below that of other Heinrich events
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The ratio of calcium versus strontium in a North Atlantic drill core (blue; Hodell et al., 2008) compared to petrologic counts of "detrital carbonate" (Bond et al., 1999; Obrochta et al., 2012; Obrochta et al., 2014), the mineralogically-distinctive component of Hudson Strait-derived IRD. Shading indicates glaciations ("ice ages").
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Present-day ocean circulation. The Gulf Stream, far left, may be redirected during Heinrich events.
See also
In Spanish: Eventos Heinrich para niños
