Rapid changes in sea ice and ocean properties are occurring in the Chukchi Sea, and there is considerable uncertainty how these changes might influence nutrient distributions and ultimately primary productivity. Although inorganic nitrogen is a limiting nutrient, there are few reports on seasonal or interannual variability of nitrate, especially those focused on wintertime replenishment of nitrate. This study examined six years of hourly measurements of nitrate at multiple mooring locations off Icy Cape between 2010 and 2018 with a focus on winter replenishment in relation to northward transport. Nitrate concentrations are lowest in newly formed winter water, and rates of local nitrate replenishment appear low relative to the nutrient flux through Bering Strait. There is considerable interannual variability in transport over the northeastern shelf of the Chukchi Sea that is driven by northerly (weakens transport) and southerly (strengthens transport) wind events. Anomalously low nitrate concentrations were observed in the winter of 2011–2012 when transport was negligible, and locally formed, low nitrate winter water remained on the shelf. During winters with the highest transport (2010–2011, 2017–2018), pre-bloom (15 May) nitrate concentrations were high and closely resembled nitrate concentrations in the Bering Sea from the previous fall. In recent years, there has been an increase in southerly wind events. As these conditions enhance total transport and nutrient flux through Bering Strait, contemporary Bering Sea water is advected onto the northern Chukchi Sea shelf. In the presence of southerly wind events, nutrient measurements in the northern Bering Sea in fall can be used to predict pre-bloom nitrate concentrations available for sustaining primary production in the eastern Chukchi Sea the following spring. Since 2005, inorganic nitrogen concentrations in the northern Bering Sea have varied between 11 and 22 μM; an indication that net community production over the eastern Chukchi Sea may have varied between ~30 and 70 g C m⁻² during this time.

楚科奇海的海冰和海洋特性迅速变化，这些变化如何影响养分分布并最终影响初级生产力存在很大的不确定性。尽管无机氮是一种限制性营养素，但很少有关于硝酸盐的季节或年际变化的报道，尤其是那些集中在冬季补充硝酸盐的报道。这项研究检查了2010年至2018年之间在冰冷海角附近多个停泊地点每小时6年的硝酸盐测量值，重点是与北向运输有关的冬季补给。在新形成的冬季水中，硝酸盐浓度最低，相对于通过白令海峡的养分流量，局部硝酸盐的补充速度似乎较低。在楚科奇海东北部陆架上，由于北风（弱风运输）和南风（强风运输）的驱动，年际运输存在很大的年际变化。在2011-2012年冬季，当运输可忽略不计时，观察到硝酸盐浓度异常偏低，而在当地形成的低硝酸盐冬季水仍留在架子上。在运输量最高的冬季（2010-2011年，2017-2018年），暴风雨前（5月15日）硝酸盐浓度很高，与去年秋天的白令海硝酸盐浓度非常相似。近年来，南风事件有所增加。由于这些条件增强了通过白令海峡的总运输和养分通量，当代白令海水被平流到楚科奇海北部海域。在出现南风的情况下，秋季白令海北部的养分测量可用于预测第二年春季楚科奇海东部维持初级生产的硝酸盐浓度。自2005年以来，白令海北部的无机氮浓度在11到22μM之间变化。表明楚科奇东部海域的净社区生产可能在30至70 g C m之间变化在这段时间内为^-2。