|
Titel |
Terminations VI and VIII (∼ 530 and ∼ 720 kyr BP) tell us the importance of obliquity and precession in the triggering of deglaciations |
VerfasserIn |
F. Parrenin, D. Paillard |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1814-9324
|
Digitales Dokument |
URL |
Erschienen |
In: Climate of the Past ; 8, no. 6 ; Nr. 8, no. 6 (2012-12-12), S.2031-2037 |
Datensatznummer |
250005984
|
Publikation (Nr.) |
copernicus.org/cp-8-2031-2012.pdf |
|
|
|
Zusammenfassung |
The main variations of ice volume of the last million years can be explained
from orbital parameters by assuming climate oscillates between two states:
glaciations and deglaciations (Parrenin and Paillard, 2003; Imbrie et al.,
2011) (or terminations). An additional combination of ice volume and orbital
parameters seems to form the trigger of a deglaciation, while only orbital
parameters seem to play a role in the triggering of glaciations. Here we
present an optimized conceptual model which realistically reproduce ice
volume variations during the past million years and in particular the timing
of the 11 canonical terminations. We show that our model looses sensitivity
to initial conditions only after ∼200 kyr at maximum: the ice
volume observations form a strong attractor. Both obliquity and precession
seem necessary to reproduce all 11 terminations and both seem to play
approximately the same role. More precisely, obliquity plays a fundamental
role in the triggering of termination VI (~530 kyr BP), while
precession plays a fundamental role in the triggering of termination VIII
(~720 kyr ago). |
|
|
Teil von |
|
|
|
|
|
|