Holocene paleoclimate data from the Arctic: testing models of global climate change
Quaternary Science Reviews, 20, (12), . (doi:10.1016/S0277-3791(01)00010-5).
Full text not available from this repository.
To evaluate the spatial variability ofArctic climate change during the present interglacial, CAPE Project Members compiled
well-dated terrestrial, marine, and ice-core paleoenvironmental records spanning the past 10}12 thousand years (ka). Six tundra
biomes ofincreasing summer temperature requirements were de"ned based on regionally coherent pollen assemblages. Using
a rule-based approach, pollen spectra were converted to tundra, forest/tundra, or forest biomes ranked by their average growing
season requirements. Marine sea-surface reconstructions were based on proxy data following a similar rule-based approach. From
these data-based reconstructions, departures in summer temperatures from modern normals were calculated in 1 ka time slices
through the Holocene. To test predictive models, data-based summer temperature reconstructions were compared with general
circulation model (GCM) simulations for 10 ka and 6 ka ago. Paleodata and model results both show that warming occurred earlier
across Beringia and Asia relative to lands adjacent to the North Atlantic, and that Late Holocene cooling was most apparent in the
North Atlantic region. However, the GCM over-predicts the magnitude ofMid-Holocene warming over northern Asia and
underestimates the intensi"cation ofthe North Atlantic drift in the early Holocene. Strong spatial variability in environmental
response during the Holocene, despite symmetric (insolation) forcing, suggests that any future changes, whether caused by
anthropogenic or natural factors, are unlikely to result in a uniform change across the Arctic, adding additional complexity to
forecasts of global impacts.
Actions (login required)