* Persistent intermediate water warming during cold
stadials in the southeastern Nordic seas during the past 65 k.y. Mohamed M. Ezat, Tine L. Rasmussen and Jeroen Groeneveld.
A prerequisite was the growth of very large Northern Hemisphere ice sheets, whose subsequent collapse created
stadial conditions that disrupted global patterns of ocean and atmospheric circulation.
Next, the rise in sea levels since the
last stadial has been slowing, thus falsifying any claims that CO2 causes sea levels to accelerate.
The chemical tracers also show that circulation slowed almost to a halt during certain
stadials known as Heinrich events, when massive amounts of icebergs broke off and drifted away from the Laurentide ice sheet, which covered a large part of North America at the time.
Glacials and interglacials can be further divided
into stadials and interstadials, and within these we have smaller scale Dansgaard - Oeschger cycles, and then even smaller cycles, such as El - Nino and ENSO.
The rise in BWT during
stadials confirms earlier interpretations of subsurface inflow of warm Atlantic water below a halocline reaching > 1.2 km water depth.
Study results which would help to explain the abruptness of the Bølling - Allerød warming, based on observations and simulations, found that 3 ° — 5 °C Ocean warming occurred at intermediate depths in the North Atlantic over several millennia during
Heinrich stadial 1 (HS1).
During every cold
northern stadial, the overturning circulation had slowed, so it wasn't bringing as much heat northward from the tropics and Southern Hemisphere, the study shows.
These are known as interstadial and
stadial periods, which occur when glaciers retreat and advance, respectively.
Mohamed M. Ezat, Tine L. Rasmussen, Jeroen Groeneveld; Persistent intermediate water warming during cold
stadials in the southeastern Nordic seas during the past 65 k.y..
High frequency oscillations in the λ 13C composition of long chain fatty acids during MIS 3 appear to coincide with Dansgaard / Oeschger variability in high latitude ice cores, with positive (negative) excursions occurring
during stadial (interstadial) periods.
Brief, inconclusive periods of advancing ice — typically lasting less than 10,000 years — are called «
stadials»; conversely, periods when the ice retreated, but only briefly, are called «interstadials».
Cold periods (
stadials) switched abruptly to warmer periods (interstadials) and back.
The study, published in Geology, documented that bottom water actually warmed up to up to 5 °C at 1200 m depth in the Nordic seas during the cold
stadials.
MIS 9 cooling trend was measured up to
a stadial event which is why it appears shorter.
Re # 135 The general opinion amongst most climate scientists and oceanographers is that a slow down in the THC will cause a cooling based on what they think happened at the start of the Younger Dryas
stadial (mini ice age.)
Despite the occurrence of inter
stadials and stadials, the researchers evaluated the overall strength of interglacials.
The results show gradual and pronounced BWT increases of 2 — 5 °C during
stadials, indicating a stop or near stop in convection.
During the last glacial period, climate underwent rapid millennial - scale variability known as Dansgaard - Oeschger (DO) events, consisting of warm inter
stadials and cold stadials.
The results suggest that warm Atlantic water never ceased to flow into the Nordic seas during the glacial period; inflow at the surface during the Holocene and warm inter
stadials changed to subsurface and intermediate inflow during cold stadials.
Each followed a general pattern in the Northern Hemisphere: The cooling happening over hundreds to 1,000 years, then the frigid temperatures persisted for a few hundred years in what is known as
a stadial, McManus said.