High-resolution Greenland ice core data show abrupt climate change happens in few years.
The last two abrupt warmings at the onset of our present warm interglacial period, interrupted by the Younger Dryas cooling event, were investigated at high temporal resolution from the North Greenland Ice Core Project ice core. The deuterium excess, a proxy of Greenland precipitation moisture source, switched mode within 1 to 3 years over these transitions and initiated a more gradual change (over 50 years) of the Greenland air temperature, as recorded by stable water isotopes. The onsets of both abrupt Greenland warmings were slightly preceded by decreasing Greenland dust deposition, reflecting the wetting of Asian deserts. A northern shift of the Intertropical Convergence Zone could be the trigger of these abrupt shifts of Northern Hemisphere atmospheric circulation, resulting in changes of 2 to 4 kelvin in Greenland moisture source temperature from one year to the next.
Steffensen
Jørgen Peder
JP
Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen OE, Denmark. jps@gfy.ku.dk
Andersen
Katrine K
KK
Bigler
Matthias
M
Clausen
Henrik B
HB
Dahl-Jensen
Dorthe
D
Fischer
Hubertus
H
Goto-Azuma
Kumiko
K
Hansson
Margareta
M
Johnsen
Sigfús J
SJ
Jouzel
Jean
J
Masson-Delmotte
Valérie
V
Popp
Trevor
T
Rasmussen
Sune O
SO
Röthlisberger
Regine
R
Ruth
Urs
U
Stauffer
Bernhard
B
Siggaard-Andersen
Marie-Louise
ML
Sveinbjörnsdóttir
Arny E
AE
Svensson
Anders
A
White
James W C
JW