Emerging dominance of summer rainfall driving High Arctic terrestrial-aquatic connectivity.
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Where this comes from
- Record sourced from PubMed, PMID 33664252.
- Also identified by DOI 10.1038/s41467-021-21759-3 and PMC identifier 7933336.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Hydrological transformations induced by climate warming are causing Arctic annual fluvial energy to shift from skewed (snowmelt-dominated) to multimodal (snowmelt- and rainfall-dominated) distributions. We integrated decade-long hydrometeorological and biogeochemical data from the High Arctic to show that shifts in the timing and magnitude of annual discharge patterns and stream power budgets are causing Arctic material transfer regimes to undergo fundamental changes. Increased late summer rainfall enhanced terrestrial-aquatic connectivity for dissolved and particulate material fluxes. Permafrost disturbances (<3% of the watersheds' areal extent) reduced watershed-scale dissolved organic carbon export, offsetting concurrent increased export in undisturbed watersheds. To overcome the watersheds' buffering capacity for transferring particulate material (30 ± 9 Watt), rainfall events had to increase by an order of magnitude, indicating the landscape is primed for accelerated geomorphological change when future rainfall magnitudes and consequent pluvial responses exceed the current buffering capacity of the terrestrial-aquatic continuum.