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|Heinrich event has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can reassess it.|
|Current status: Good article|
|WikiProject Geology||(Rated GA-class, Mid-importance)|
Serious fact error in estimated water volume
In the second paragraph of the "Diagnosis of Heinrich events", it is stated that "Alley & MacAyeal (1994) estimate the volume of fresh water added to the North Atlantic over each 500 year event at around 3.7±1.2×10¹¹ km³ — a huge influx of cold, fresh water that would have had global effects." This is totally wrong, in several ways. The cited numbers "3.7±1.2×10¹¹" refers to IRD (ice-rafted debris), not water. And it is given in cubic meters (m³), NOT cubic kilometers (km³). Quote from Alley & MacAyeal (1994): "Assuming that IRD has a density of 2700 kg m³, the m [mass] we estimate corresponds to an IRD volume of 3.7±1.2×10¹¹ m³". Actually, 3.7±1.2×10¹¹ km³ of water is almost 300 times the total global ocean volume (ca 1.3×109km³, http://en.wikipedia.org/wiki/Ocean), a freshwater contribution that indeed would have global effects.
I suggest that the sentence in question is replaced by this: During Heinrich events, huge volumes of fresh water flow into the ocean. For Heinrich event 4, the fresh water flux has been estimated to 0.29±0.05 Sverdrup (http://en.wikipedia.org/wiki/Sverdrup) with a duration of 250±150 years (Roche et al., 2004), equivalent to a fresh water volume of about 2.3 million km³.
Alley, R.B.; MacAyeal, D.R. (1994). "Ice-rafted debris associated with binge/purge oscillations of the Laurentide Ice Sheet". Paleoceanography 9 (4): 503-512. DOI:10.1029/94PA01008.
Roche, D., Paillard, D., Cortijo, E. (2004). "Duration and iceberg volume of Heinrich event 4 from isotope modelling study, Nature 432: 379–382. Cutnell, J. D., and Johnson, K. W.(1995). Physics, 3rd Edition. New York: Wiley: p315. 22.214.171.124 12:18, 27 September 2007 (UTC)
- I think you are right here, I actually did not check the numbers, when I reviewed it. Ruslik 12:41, 27 September 2007 (UTC)
GA Sweeps Review: Pass
As part of the WikiProject Good Articles, we're doing sweeps to go over all of the current GAs and see if they still meet the GA criteria. I'm specifically going over all of the "Meteorology and atmospheric sciences" articles. I believe the article currently meets the criteria and should remain listed as a Good article. I have made several minor corrections throughout the article. Altogether the article is well-written and is still in great shape after its passing in 2007. Continue to improve the article making sure all new information is properly sourced and neutral. It would also be beneficial to go through the article and update all of the access dates of the inline citations and fix any dead links. If you have any questions, let me know on my talk page and I'll get back to you as soon as I can. I have added an article history to reflect this review. Happy editing! --Nehrams2020 (talk) 21:43, 24 April 2008 (UTC)
126.96.36.199 left this comment in the article:
- "Ice provenance: Icebergs in H1, H2, H4, and H5 appear to have flowed along the Hudson Strait; H3 and H6 icebergs appear to have flowed across it (just WRONG: read literature before write this crap again, ok? Kirkby and Andrews, 1999)."
I read this article because I had just watched a TV programme in which Clive Finlayson argued that the Neanderthals went extinct because they could not cope with the rapid climate fluctuations during the Heinrich events, which changed Europe from forest to tundra. The article did not help answer what I would like to know about Heinrich events. What were their effects on ecosystems and is Finlayson right? He makes the same point in a Scientific American article at http://www.scientificamerican.com/article.cfm?id=the-mysterious-downfall.
What was the reduction in temperature in each Heinrich event, and how does it compare with earlier ice ages. I find the Heinrich event chart unhelpful. The lines do not appear to me to have any clear relation to the H events and do not have a temperature parameter. There is a much clearer chart, Vostok Petit data, in the Quaternary glaciation article, http://en.wikipedia.org/wiki/File:Vostok_Petit_data.svg, which shows H2, H5 and H6 clearly, and that H2 was the most extreme (as the TV programme says but the Heinrich article does not) and also suggests that there were similar fluctuations between 130,000 and 180,000 years ago, although the Heinrich article says that there is no data for earlier periods. I would suggest replacing the confusing Heinrich events chart with the informative Vostok one.
How do the Heinrich events relate to the Older and Oldest Dryas? The date for H1 appears to be similar to the Oldest Dryas.
This is outside my field, so excuse me if I am making unfair criticisms through ignorance. Dudley Miles 00:58, 30 July 2011 (UTC) http://triksgretz.blogspot.com/ — Preceding unsigned comment added by Budi354 (talk • contribs) 09:55, 26 December 2011 (UTC)
The graphs are shown on different timescales
This is a comment to the plot in the article. Heinrich events are shown on a GISP2 timescale while Greenland icecore data are shown on a NGRIP/GRIP timescale. This places the Heinrich events wrong with respect to the Greenland icecore record. The Anarctic icecore data are also shown on a different time scale. Please put all the curves on a synchronous timescale and inform which timescale has been used. 188.8.131.52 (talk) 11:35, 10 June 2013 (UTC)