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.
2008. Vol. 321, 680-684 p.