Search for: All records

Abstract Newly ventilated winter water (NVWW) is a cold, salty, nutrient‐rich water mass that is critical for supporting the ecosystem of the western Arctic Ocean and for ventilating the halocline in the Canada Basin. While the formation of NVWW is well‐documented on the Chukchi shelf, there remain fundamental questions regarding its formation on the western Beaufort shelf. In this study, we use hydrographic data from two late‐fall cruises in 2018 and 2022 to investigate the roles of sea ice production and wind‐driven upwelling in the formation of NVWW and the implications for the nutrient content of the water. For each of the shipboard transects, we apply proxies for the extent of the winter water formation and the strength of the associated upwelling, respectively. It is demonstrated that the NVWW attains higher levels of nitrate due to two factors: (a) more active formation of the water associated with enhanced sea ice production and (b) more extensive upwelling of water high in nutrients from the basin to the shelf following an easterly wind event. The latter process would be less common on the wide Chukchi shelf. These findings have significant implications for the regional primary production. 

Abstract This article evaluates the predictions of an algorithmic‐level distributed associative memory model as it introduces, propagates, and resolves ambiguity, and compares it to the predictions of computational‐level parallel parsing models in which ambiguous analyses are accounted separately in discrete distributions. By superposing activation patterns that serve as cues to other activation patterns, the model is able to maintain multiple syntactically complex analyses superposed in a finite working memory, propagate this ambiguity through multiple intervening words, then resolve this ambiguity in a way that produces a measurable predictor that is proportional to the log conditional probability of the disambiguating word given its context, marginalizing over all remaining analyses. The results are indeed consistent in cases of complex structural ambiguity with computational‐level parallel parsing models producing this same probability as a predictor, which have been shown reliably to predict human reading times.