Abstract. Anthropogenic warming in the Arctic is causing hydrological cycle intensification and permafrost thaw, with implications for flows of water, carbon, and energy from terrestrial biomes to coastal zones. To better understand the likely impacts of these changes, we used a hydrology model driven by meteorological data from atmospheric reanalysis and two global climate models for the period 1980–2100. The hydrology model accounts for soil freeze–thaw processes and was applied across the pan-Arctic drainage basin. The simulations point to greater changes over northernmost areas of the basin underlain by permafrost and to the western Arctic. An acceleration of simulated river discharge over the recent past is commensurate with trends drawn from observations and reported in other studies. Between early-century (2000–2019) and late-century (2080–2099) periods, the model simulations indicate an increase in annual total runoff of 17 %–25 %, while the proportion of runoff emanating from subsurface pathways is projected to increase by 13 %–30 %, with the largest changes noted in summer and autumn and across areas with permafrost. Most notably, runoff contributions to river discharge shift to northern parts of the Arctic Basin that contain greater amounts of soil carbon. Each season sees an increase in subsurface runoff; spring is the only season where surface runoff dominates the rise in total runoff, and summer experiences a decline in total runoff despite an increase in the subsurface component. The greater changes that are seen in areas where permafrost exists support the notion that increased soil thaw is shifting hydrological contributions to more subsurface flow. The manifestations of warming, hydrological cycle intensification, and permafrost thaw will impact Arctic terrestrial and coastal environments through altered river flows and the materials they transport.
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Assessment of Influences of Anthropogenic and Climatic Changes in the Drainage Basin on Hydrological Processes in the Gulf of Ob
Changes in the runoff of rivers flowing into the Arctic Ocean caused by climate changes and increasing anthropogenic load lead to foreseeable transformations of hydrological processes in the mouth areas of the rivers. Climatic, water-balance, and hydrodynamic models were successively applied to evaluate the effect of climatic and anthropogenic changes in the drainage basin of the Ob river estuary on seasonal hydrological processes in the Gulf of Ob. Climate changes along with considerable seasonal redistribution of river runoff in the drainage basin of the Gulf of Ob, mostly due to its increase in winter, were found to cause no significant changes in the seasonal hydrological mouth processes in 1980–2018. Estimates for a period of up to 2050 showed that climate changes under various scenarios will cause an increase in streamf low from the basin, which will reduce the penetration of saltwater into the gulf.
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- Award ID(s):
- 1917515
- PAR ID:
- 10433765
- Date Published:
- Journal Name:
- Water resources
- Volume:
- 49
- Issue:
- 5
- ISSN:
- 0097-8078
- Page Range / eLocation ID:
- 608-624
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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