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Abstract The electrochemical detection of two pharmaceuticals, diclofenac (DCF) and carbamazepine (CBZ), was investigated as an oxidation current using boron‐doped nanocrystalline diamond (BDD) thin‐film electrodes. Both voltammetry and flow injection analysis with amperometric detection (FIA‐EC) were used to measure the drugs in standard solutions and a urine simulant. The oxidation potential for DCF wasca. 0.7 V vs. Ag/AgCl (3 M KCl) in 0.1 M phosphate buffer (pH 7.2) and wasca. 1.2 V for CBZ in 0.1 M perchloric acid. The DCF oxidation reaction was diffusion controlled at the detection potential with evidence of some surface fouling by reaction products. The CBZ oxidation reaction was also controlled by diffusion at the detection potential, but with no surface fouling. The voltammetric peak currents for both drugs increased linearly with the concentration in the micromolar range (r²≥0.994). FIA‐EC analysis of DCF and CBZ revealed a linear dynamic range from at least 0.1 to 100 μM with the actual minimum concentration detectable (S/N=3) being less than the lowest concentration measured. The recovery percentage for DCF in the urine simulant ranged from 94–108% and from 97–100% for CBZ, both assessed using square wave voltammetry. FIA‐EC data revealed that the BDD electrodes offer excellent intra and inter‐electrode repeatability with an RSD for DCF and CBZ of 4.90% and 3.81%, respectively. The BDD electrode provided good reproducibility and response stability over eight days of continuous use detecting both DCF and CBZ. Overall, BDD electrodes are a viable material  for the sensitive, selective, and reproducible electrochemical detection of these two pharmaceuticals. 

Abstract In early December 2020, an atmospheric river (AR) and rain-on-snow (ROS) event impacted the Haines, Alaska area, resulting in record-breaking rainfall and snowmelt that caused flooding and dozens of mass movement events. We consider the AR—a one-in-500-year event—as the trigger for the devastating Beach Road Landslide (BRLS), which destroyed or damaged four residences and took the lives of two people. The BRLS started as a debris avalanche and transitioned into a debris flow, with a total approximate landslide volume of 187,100 m³. Geomorphic analysis using lidar data identified evidence of paleo-landslides and displaced masses of rock, one of which served as the source area for the BRLS. Significant structural features in the weak ultramafic bedrock defined the head scarp area and formed the failure plane. This study illustrates the importance of identifying pre-existing landslide features and source areas likely to produce future landslides. As an increase in ROS events is projected for Southeast Alaska with warmer and wetter winters, we recommend the development of an AR scale coupled with geological information for the region, to enhance warnings to residents in landslide-prone areas.