Glen M. MacDonald

TL;DR: A compilation of paleoclimate records from lake sediments, trees, glaciers, and marine sediments provides a view of circum-Arctic environmental variability over the last 400 years.

TL;DR: The spatial pattern of lake disappearance suggests (i) that thaw and "breaching" of permafrost is driving the observed losses, by enabling rapid lake draining into the subsurface; and (ii) a conceptual model in which high-latitude warming ofpermafrost triggers an initial but transitory phase of lake and wetland expansion, followed by their widespread disappearance.

TL;DR: In this paper, a spatio-temporal pattern of peak Holocene warmth (Holocene thermal maximum, HTM) is traced over 140 sites across the Western Hemisphere of the Arctic (0−180°W; north of ∼60°N).

TL;DR: This article used tree-ring chronologies from Pinus flexilis in California and Alberta to produce an AD 993-1996 reconstruction of the Pacific Decadal Oscillation (PDO) and to assess long-term variability in the PDO's strength and periodicity.

TL;DR: Interpolar methane gradient (IPG) data from ice cores suggest the “switching on” of a major Northern Hemisphere methane source in the early Holocene, and Russia's West Siberian Lowland represents a long-term carbon dioxide sink and global methane source since theEarly Holocene.