Holocene hydroclimatic reorganizations in northwest Canada inferred from lacustrine carbonate oxygen isotopes

G. Everett Lasher; Mark B. Abbott; Lesleigh Anderson; Lindsey Yasarer; Michael Rosenheimer; Bruce P. Finney

doi:10.1029/2021gl092948

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Holocene hydroclimatic reorganizations in northwest Canada inferred from lacustrine carbonate oxygen isotopes

G. Everett Lasher·Mark B. Abbott·Lesleigh Anderson·Lindsey Yasarer·Michael Rosenheimer·Bruce P. Finney

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Abstract

Sub-centennial oxygen ( δ 18 O) isotopes of ostracod and authigenic calcite from Squanga Lake provides evidence of hydroclimatic extremes and a series of post-glacial climate system reorganizations for the interior region of northwest Canada. Authigenic calcite δ 18 O values range from −16‰ to −21‰ and are presently similar to modern lake water and annual precipitation values. Ostracod δ 18 O record near identical trends with calcite, offset by +1.7 ± 0.6‰. At 11 ka BP (kaBP = thousands of years before 1950), higher δ 18 O values reflect decreased precipitation−evaporation (P−E) balance from residual ice sheet influences on moisture availability. A trend to lower δ 18 O values until ∼8 ka BP reflects a shift to wetter conditions, and reorganization of atmospheric circulation. The last millennium and modern era are relatively dry, though not as dry as the early Holocene extreme. North Pacific climate dynamics remained an important driver of P−E balance in northwest Canada throughout the Holocene.

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Geophysical Research Letters Article

Source-reported bounding extent: 59.84481485969105° to 69.68761843185617° latitude; -141.240234375° to -123.662109375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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G. Everett Lasher, Mark B. Abbott, Lesleigh Anderson, Lindsey Yasarer, Michael Rosenheimer, Bruce P. Finney. 2021-08-16. Holocene hydroclimatic reorganizations in northwest Canada inferred from lacustrine carbonate oxygen isotopes. https://doi.org/10.1029/2021gl092948

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