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1. Biogeochemical River Runoff Drives Intense Coastal Arctic Ocean CO 2 Outgassing

   https://doi.org/10.1029/2022GL102377  

   Bertin, C. ; Carroll, D. ; Menemenlis, D. ; Dutkiewicz, S. ; Zhang, H. ; Matsuoka, A. ; Tank, S. ; Manizza, M. ; Miller, C. E. ; Babin, M. ; et al ( April 2023 , Geophysical Research Letters)

   Key Points Mackenzie River biogeochemical discharge decreases the southeastern Beaufort Sea carbon sink Terrestrial dissolved inorganic carbon (DIC) is the primary driver of outgassing events in the SBS, followed by terrestrial DOC Interannual variability in river discharge modulates localized air‐sea CO 2 flux 

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2. Changing characteristics of runoff and freshwater export from watersheds draining northern Alaska

   https://doi.org/10.5194/tc-13-3337-2019  

   Rawlins, Michael A. ; Cai, Lei ; Stuefer, Svetlana L. ; Nicolsky, Dmitry ( January 2019 , The Cryosphere)

   Abstract. The quantity and quality of river discharge in Arctic regions is influenced by many processes including climate, watershed attributes and, increasingly, hydrological cycle intensification and permafrost thaw. We used a hydrological model to quantify baseline conditions and investigate the changing character of hydrological elements for Arctic watersheds between Utqiagvik (formerly known as Barrow)) and just west of Mackenzie River over the period 1981–2010. A synthesis of measurements and model simulations shows that the region exports 31.9 km3 yr−1 of freshwater via river discharge, with 55.5 % (17.7 km3 yr−1) coming collectively from the Colville, Kuparuk, and Sagavanirktok rivers. The simulations point to significant (p<0.05) increases (134 %–212 % of average) in cold season discharge (CSD) for several large North Slope rivers including the Colville and Kuparuk, and for the region as a whole. A significant increase in the proportion of subsurface runoff to total runoff is noted for the region and for 24 of the 42 study basins, with the change most prevalent across the northern foothills of the Brooks Range. Relatively large increases in simulated active-layer thickness (ALT) suggest a physical connection between warming climate, permafrost degradation, and increasing subsurface flow to streams and rivers. A decline in terrestrial water storage (TWS) is attributed to losses in soil ice that outweigh gains in soil liquid water storage. Over the 30-year period, the timing of peak spring (freshet) discharge shifts earlier by 4.5 d, though the time trend is only marginally (p=0.1) significant. These changing characteristics of Arctic rivers have important implications for water, carbon, and nutrient cycling in coastal environments. 

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3. Connectivity of post‐fire runoff and sediment from nested hillslopes and watersheds

   https://doi.org/10.1002/hyp.13975  

   Wilson, Codie ; Kampf, Stephanie K. ; Ryan, Sandra ; Covino, Tim ; MacDonald, Lee H. ; Gleason, Hunter ( November 2020 , Hydrological Processes)

   Wildfire increases the potential connectivity of runoff and sediment throughout watersheds due to greater bare soil, runoff and erosion as compared to pre‐fire conditions. This research examines the connectivity of post‐fire runoff and sediment from hillslopes (<1.5 ha;n= 31) and catchments (<1000 ha;n= 10) within two watersheds (<1500 ha) burned by the 2012 High Park Fire in northcentral Colorado, USA. Our objectives were to: (1) identify sources and quantify magnitudes of post‐fire runoff and erosion at nested hillslopes and watersheds for two rain storms with varied duration, intensity and antecedent precipitation; and (2) assess the factors affecting the magnitude and connectivity of runoff and sediment across spatial scales for these two rain storms. The two summer storms that are the focus of this research occurred during the third summer after burning. The first storm had low intensity rainfall over 11 hours (return interval <1–2 years), whereas the second event had high intensity rainfall over 1 hour (return interval <1–10 years). The lower intensity storm was preceded by high antecedent rainfall and led to low hillslope sediment yields and channel incision at most locations, whereas the high intensity storm led to infiltration‐excess overland flow, high sediment yields, in‐stream sediment deposition and channel substrate fining. For both storms, hillslope‐to‐stream sediment delivery ratios and area‐normalised cross‐sectional channel change increased with the percent of catchment that burned at high severity. For the high intensity storm, hillslope‐to‐stream sediment delivery ratios decreased with unconfined channel length (%). The findings quantify post‐fire connectivity and sediment delivery from hillslopes and streams, and highlight how different types of storms can cause varying magnitues and spatial patterns of sediment transport and deposition from hillslopes through stream channel networks.

    

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4. Streamflow variability controls N and P export and speciation from Alaskan coastal temperate rainforest watersheds

   https://doi.org/10.1007/s10533-020-00752-w  

   Fellman, Jason B. ; Hood, Eran ; D’Amore, David V. ; Edwards, Richard T. ( February 2021 , Biogeochemistry)

   null (Ed.)
5. Propagation of future climate conditions into hydrologic response from coastal southern California watersheds

   https://doi.org/10.1007/s10584-019-02371-3  

   Feng, Dongmei ; Beighley, Edward ; Raoufi, Roozbeh ; Melack, John ; Zhao, Yuanhao ; Iacobellis, Sam ; Cayan, Daniel ( March 2019 , Climatic Change)