[Coral-List] Ocean Temperatures Suddenly Over the Tipping Point?

Mon Jul 10 21:48:04 UTC 2023

Smith, J., Risk, M., Schwarcz, H. *et al.* Rapid climate change in the
North Atlantic during the Younger Dryas recorded by deep-sea corals.
*Nature* 386, 818–820 (1997).

Abstract

Research on global climate change has increasingly focused on rapid
(century-scale and decadal) changes. One such climate shift, the Younger
Dryas cooling event1, took place during the last deglaciation, from 13,000
to 11,700 years BP. Climate records from Greenland ice cores and North
Atlantic sediment cores show high-frequency fluctuations implying
significant (>5 °C) shifts in temperature at this time, taking place within
50–100 years (ref. 2). The origin of the Younger Dryas has recently been
attributed to a reduction or cessation of deep-water production in the
North Atlantic and a concurrent lessening of the heat flux from low
latitudes3,4. The role of intermediate waters (1,000–2,000 m depth) is less
certain, however, because climate proxies for this ocean reservoir are rare
and ambiguous. Here we report on the use of a new climate archive, deep-sea
corals from Orphan knoll (1,600m depth) in the northwestern Atlantic Ocean.
The oxygen isotope ratios in the coral skeletons (accurately dated by the
230Th/234U chronometric method) change markedly coincident with the
initiation of the Younger Dryas, suggesting that there were profound
changes in intermediate-water circulation at this time.

Not open-access.

 (amazing what you can find on Google Scholar.)

Cheers, Doug

On Mon, Jul 10, 2023 at 4:27 AM Risk, Michael via Coral-List <
coral-list at coral.aoml.noaa.gov> wrote:

>    Austin:
>
>    This is a list devoted (supposedly) to corals. Re the Atlantic
>    circulation: in 1997 (Smith et al, Science), using data obtained from a
>    suite of deepwater corals,  we suggested that the collapse could take
>    place in less than 5 years. Of course, we don't know when the meter
>    started running-we could be 4 years into this already.
>
>    Mike
>      __________________________________________________________________
>
>    From: Coral-List <coral-list-bounces at coral.aoml.noaa.gov> on behalf of
>    Austin Bowden-Kerby via Coral-List <coral-list at coral.aoml.noaa.gov>
>    Sent: Sunday, July 9, 2023 6:14 PM
>    To: Coral-List Subscribers <coral-list at coral.aoml.noaa.gov>
>    Subject: [Coral-List] Ocean Temperatures Suddenly Over the Tipping
>    Point?
>
>    Caution: This email may have originated from outside the organization.
>    Please exercise additional caution with any links and attachments.
>    Dear everyone,
>    I am posting this because it is time for everyone to look up from our
>    busy
>    lives and face a new reality.  It looks like we have gone over a major
>    tipping point, but judge for yourself.
>    Something happened to cause the average temperature of the ocean to
>    suddenly jump by about 0.7C from the 1982-2011average, and it is not El
>    Nino. The graph is absolutely shocking.
>    [1]https://climatereanalyzer.org/clim/sst_daily/   The graphs are
>    updated
>    daily.
>    Unfortunately as far as the timeline to 1.5C, all of the former
>    information
>    has suddenly become inaccurate. We went above the 1.5C threshold in
>    June.
>    [2]https://www.ecmwf.int/en/about/media-centre/news/2023/copernicus-rec
>    ords-first-june-breach-15degc-climate-threshold
>    And these temperatures are now holding.
>    This crazy and almost unbelievable jump in temperature appears to be
>    related to the delayed impacts of the Tonga eruption.
>    [3]https://www.carbonbrief.org/tonga-volcano-eruption-raises-imminent-r
>    isk-of-temporary-1-5c-breach/
>     But the increase is much worse than what these atmospheric scientists
>    predicted back in January.  They say that the temporary heating effects
>    of
>    the water vapor in the upper atmosphere will last for five years, but I
>    read elsewhere that it could be a decade.
>    But my Question now is this: what If the Atlantic overturning
>    circulation
>    were to suddenly collapse due to this being superimposed on
>    anthropogenic Carbon emissions?  And how long would it take for us to
>    even
>    know, and when that happens, how long will it take before the surface
>    waters of the ocean warm up (like we are seeing now)?
>    [4]https://www.washingtonpost.com/weather/2023/06/23/ocean-heatwave-nor
>    thatlantic-uk-climate/
>    The photos of severe bleaching in Belize, posted on Facebook by
>    Fragments
>    of Hope, are heartbreaking.  It started in June, and the only source of
>    relief will be a near-miss hurricane or tropical storm.
>    Have we suddenly fast-forwarded 27 years to 2050 conditions?
>    Austin
>    Austin Bowden-Kerby, PhD
>    Corals for Conservation
>    [5]https://www.corals4conservation.org
>    Publication on C4C's coral-focused climate change adaptation
>    strategies:
>    [6]https://www.mdpi.com/2673-1924/4/1/2/pdf
>    Film on our "Reefs of Hope" coral restoration for climate change
>    adaptation
>    strategies:  [7]https://www.youtube.com/watch?v=BG0lqKciXAA
>    [8]https://www.globalgiving.org/projects/emergency-response-to-massive-
>    coral-bleaching/
>    <[9]https://www.globalgiving.org/projects/emergency-response-to-massive
>    -coral-bleaching/>
>    >
>    _______________________________________________
>    Coral-List mailing list
>    Coral-List at coral.aoml.noaa.gov
>    [10]https://coral.aoml.noaa.gov/mailman/listinfo/coral-list
>
> References
>
>    1. https://climatereanalyzer.org/clim/sst_daily/
>    2.
> https://www.ecmwf.int/en/about/media-centre/news/2023/copernicus-records-first-june-breach-15degc-climate-threshold
>    3.
> https://www.carbonbrief.org/tonga-volcano-eruption-raises-imminent-risk-of-temporary-1-5c-breach/
>    4.
> https://www.washingtonpost.com/weather/2023/06/23/ocean-heatwave-northatlantic-uk-climate/
>    5. https://www.corals4conservation.org/
>    6. https://www.mdpi.com/2673-1924/4/1/2/pdf
>    7. https://www.youtube.com/watch?v=BG0lqKciXAA
>    8.
> https://www.globalgiving.org/projects/emergency-response-to-massive-coral-bleaching/
>    9.
> https://www.globalgiving.org/projects/emergency-response-to-massive-coral-bleaching/
>   10. https://coral.aoml.noaa.gov/mailman/listinfo/coral-list
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