A. Rates of temperature rise from the mid-19th century are higher than those of
the glacial termination (17 — 10 kyr) by more than a factor of 10, increasing to a factor of 20 and higher from the mid-1970s.
C. Rates of CO2 increase from the late 19th century (~ 0.6 — 0.7 ppm / yr) are almost a factor of 50
the glacial termination rates (~ 0.014 ppm / yr), accelerating during 2000 — 2005 from 1.8 to 2.1 ppm / year.
Rates of CO2 rise during 1970 - 2003 exceeded those of the last
glacial termination by two orders of magnitude.
(Other sources: Atmospheric CO2 Concentrations over the Last
Glacial Termination, New constraints on the gas age - ice age difference along the EPICA ice cores, 0â $ «50 kyr)
During the last
glacial termination (~ 19 — 10 kyr) sharp increase in solar insolation forcing, amplified by feeback by GHG (17 — 11.5)(Table 1), resulted in mean temperature increase of about 90 C [2].
Temperature rise rates during 1970 - 2003 have exceeded those of the last
glacial termination by an order of magnitude.
According to Petit et al. [2] the same sequence of events in
each glacial termination involved «orbital forcing (with a possible contribution of local insolation changes) followed by two strong amplifiers, greenhouse gases acting first, then deglaciation and ice - albedo feedback».
Atmospheric CO2 Concentrations over the Last
Glacial Termination (Science, Vol.
BBD, «If you disagree with this, please explain how we got the YD * without * orbitally forced
glacial termination.
TTanganyika temperatures follow Northern Hemisphere insolation and indicate that warming in tropical southeast Africa during the last
glacial termination began to increase 3000 years before atmospheric carbon dioxide concentrations.
8), these stratigraphic features substantiate the use of the TP age to date
glacial termination VI at.
Variations in the methane interpolar gradient during the last
glacial termination.
Publication: Antarctic ice shield discharge driven by atmosphere - ocean feedbacks at the Last
Glacial Termination, DOI: 10.1038 / srep39979
Does this process run freely, or is it synchronized to some other forcing — like Huybers & Wunsch propose for ice ages in «Obliquity pacing of the late Pleistocene
glacial terminations»?
Glacial terminations are indicated using Roman numerals in subscript (for example TVIII); MIS denotes Marine Isotope Stage27.
Glacial terminations are indicated using Roman numerals in subscript (for example TI); Marine Isotope Stages (MIS) are given in italic Arabic numerals27.
«The lags of CO2 with respect to the Antarctic temperature over
glacial terminations V to VII are 800, 1600, and 2800 years, respectively, which are consistent with earlier observations during the last four glacial cycles.»
Resulting CH4 releases to the atmosphere / ocean system provided crucial amplification to «jump - start» rapid warmings at stadial and
glacial terminations that were significantly reinforced by other greenhouse gases, especially water vapor.
[13] Hubertus Fischer, Martin Wahlen, Jesse Smith, Derek Mastroianni, Bruce Deck, «Ice Core Records of Atmospheric CO2 around the Last Three
Glacial Terminations,» Science, vol.
As there is a lot of talk of the see - saw mechanism (in decadal - centurial scale) during
the glacial terminations, might this effect be noticeable also in shorter periods of time?
Which model came close to reproduce abrupt
glacial terminations?
Not exact matches
Martinson and Pitman III discuss of the «abrupt
terminations» of
glacial period.
After a relatively stable MIS 2 period,
Termination 1 is marked by a rapid 13C depletion over the
Glacial - Bolling transition followed by a return to somewhat heavier values during the Younger Dryas, similar to earlier observations [1].
Amplitude and Duration: The most significant events are
terminations of the
glacial period and rapid onset of global warming of the interglacial period.
Terminations I through V are significant paleoclimate events where the
termination of the
glacial state occurs, and Earth begins to change into a warm interglacial state.
For one, the relative roles of eccentricity, obliquity, and precession in controlling
glacial onsets /
terminations are still debated.
I have also seen your comments on WUWT where I read about your ideas on the
termination of the
glacial periods from a low vegetation / high dust environment as a result of low CO2 levels at the
glacial peaks, which seems very plausible to me.
Few people have read paleo - climatology text books, are aware of the
glacial / interglacial cycle, are aware that the paleoclimatic record has unequivocal evidence of cyclic gradual changes and cyclic abrupt climate events, are aware that the abrupt climate change events such as the abrupt
termination of the last 22 interglacial periods lacks an explanation, are aware that all of the past interglacial periods are short (roughly 12,000 years) and that they have ended abruptly, and so on.
After the
termination of the
glacial period, temperatures increased steadily to a maximum of 2.5 °C warmer than at present during the Climatic Optimum (4,000 to 7,000 years ago).
The interglacial and the
glacial planetary temperature data shows cycles of warming and cooling interrupted by very strong «RCEs» (Rickies) Rapid Climatic Change Events (For example the Younger Dryas abrupt cooling event and the
termination of the last interglacial).
It's attractive in that it explains several lines of otherwise problematic evidence (near - ubiquitous
glacial sediments, including many in paleo - low latitudes as indicated by paleomagnetic studies, overlain by equally ubiquitous «cap carbonates» (resulting from a CO2 insolubility spike at Snowball Earth
termination).
[DOI: 10.1126 / science.1177840]-RRB- correlated speleotherm, ice core, and marine records to show a sequence of events that led to
termination of
glacials in the past: 1.
Concurrent with mwp - 1A was the onset of the Bølling - Allerød interstadial event (14,600 years before the present), which marked the
termination of the last
glacial period.
Martinson and Pitman III discuss of the «abrupt
terminations» of
glacial period.
------- * Not to mention that there is an event similar to the Younger Dryas at the end of at least one other
glacial period, «
termination III» (see e.g. Carlson et al., 2008).