Collaborative Research: The WArming and irRadiance Measurement (WARM) buoy: Assessing the role of solar energy in heating, photosynthesis, and photo-oxidation in the upper Arctic

这个温暖的浮标收集北极海冰下的光、温度、盐度和浮游植物丰度的测量数据。北极冰层持续变薄，季节性程度减少，导致穿透冰层和进入下方海洋的日光量发生变化，对物理和生物环境产生了影响。被冰下的海洋吸收的阳光会导致变暖，这可能会导致冰层加速融化，从而导致更多的阳光进入海洋。此外，海水变暖还会影响生物，影响适应北极的物种的生存能力，并可能促进亚北极物种向北推进。更薄的冰还会增加可用于光合作用的光线，影响浮游植物繁衍的时间。如果浮游植物的生长发生在季节的早期，那么以浮游动物为食的生物可能会错过水华，从而对整个北极食物网造成后果。该项目旨在通过使用自主浮标来提供观测，以帮助确定冰下环境是如何变化的，这种浮标克服了船载观测的局限性。事实证明，这些浮标非常坚固，可以存活大约一年，提供每小时一次的观测，将近乎实时地提供给研究界和感兴趣的公众团体。浮标将于初春部署在波弗特海西部，预计将向西漂移到楚科奇大陆架上空。该项目将通过改进现有的设计来继续温暖的浮标倡议，包括提高温度和光线测量的垂直分辨率，增加盐度测量以便于识别水团，以及第二个荧光仪以识别下沉的浮游植物生物量。收集的数据将在一个完整的季节周期内提供重要的物理和生物地球化学特性的时间序列。它将使我们能够解决与更薄和更开放的冰包对太阳辐射的吸收、海洋加热、远洋初级生产力的物候和碳循环的影响有关的问题。事实证明，这些浮标非常坚固，可以存活大约一年，提供每小时一次的观测，将近乎实时地提供给研究界和感兴趣的公众团体。浮标将于初春部署在波弗特海西部，预计将向西漂移到楚科奇大陆架上空。北极冰盖起到了屏障的作用，控制着紫外线和可见光对水柱的可用性。北冰洋季节性冰的持续变薄和减少导致穿透北冰洋上层的太阳辐射的时间和强度发生了变化。太阳辐射吸收到海洋的放大作用使表层变暖和分层，这可能导致进一步的冰消退和延缓秋季冻结。由此产生的热分层通过限制营养物质的垂直补充而影响生态系统，从而直接影响初级生产力的大小。更温暖的水柱还可以在设定浮游生物群落丰度和分布的门槛、影响营养效率和促进亚北极物种向北推进方面发挥基本作用。较薄的冰增加了可用于光合作用和净初级生产的光，影响了初级生产的时间。浮游植物水华和浮游动物繁殖周期之间微小的时间错配可能会对整个脂质驱动的北极海洋生态系统产生后果。在更长的开放水域期间改变紫外线照射的持续时间，有可能增加陆地和海洋有机物的光化学再矿化作用，并产生可供微生物利用的不稳定的有机物质。确定太阳辐射变化对变暖、初级生产力和光化学的影响，对于评估和预测气候变化对海洋碳循环的影响都是至关重要的。由于船舶观测的局限性，季节性冰层内部和之下的这些变量的测量是具有挑战性的，但这可以通过使用部署在冰层内的自主温暖浮标来解决，这些浮标被设计成在冰融化时幸存下来。

The WARM buoy collects measurements of light, temperature, salinity and phytoplankton abundance under the Arctic sea ice. The Arctic ice pack has suffered continued thinning and reduction in seasonal extent, resulting in changes to the amount of sunlight penetrating through the ice and into the ocean beneath, having consequences for the physical and biological environment. Sunlight absorbed by the ocean under the ice causes warming, which can lead to accelerated ice melt resulting in even more sunlight reaching the ocean. In addition, warmer water also affects living organisms, influencing the ability of Arctic adapted species to survive, and possibly promoting the northward advancement of sub-Arctic species. Thinner ice also increases light available for photosynthesis, affecting the timing of phytoplankton blooms. If phytoplankton growth occurs early in the season then zooplankton, the organisms that feed on them can miss the bloom with consequences for the entire food web of the Arctic. This project aims to provide observations to help determine how the under-ice environment is changing by using autonomous buoys which overcome the limitations of ship-based observations. The buoys have proven to be very robust and can survive for approximately one year, providing hourly observations which will be available in near-real time to the research community and interested public parties. The buoys will be deployed in early spring in the western Beaufort Sea, with anticipated drift west over the Chukchi Shelf. This project will continue the WARM buoy initiative by improving the existing design to include increased vertical resolution of temperature and light measurements, the addition of salinity measurement to enable water mass identification, and a second fluorometer to identify sinking phytoplankton biomass. The data collected will provide a time series of important physical and biogeochemical properties over a complete seasonal cycle. It will enable us to address questions related to the effects of a thinner and more open ice pack on the absorption of solar radiation, ocean heating, the phenology of pelagic primary production, and carbon cycling. The buoys have proven to be very robust and can survive for approximately one year, providing hourly observations which will be available in near real time to the research community and interested public parties. The buoys will be deployed in early spring in the western Beaufort Sea, with anticipated drift west over the Chukchi Shelf. The Arctic ice pack acts as a barrier controlling the availability of UV and visible light to the water column. Continued thinning and reduction of seasonal Arctic ice has resulted in alterations in the timing and magnitude of solar radiation penetrating the upper Arctic Ocean. Amplification of solar radiation absorption into the ocean acts to warm and stratify the surface layer, which can induce further ice retreat and delay fall freeze-up. Resulting thermal stratification affects the ecosystem by limiting vertical replenishment of nutrients with a direct consequence on the magnitude of primary production. A warmer water column can also play a fundamental role in setting thresholds for the abundance and distribution of plankton communities, affecting trophic efficiency and promoting the northward advancement of sub-Arctic species. Thinner ice increases the light available for photosynthesis and net primary production, affecting the timing of primary production. Small timing mis-match between phytoplankton blooms and zooplankton reproductive cycles can have consequences for the entire lipid-driven Arctic marine ecosystem. Changes in the duration of UV exposure through longer open water periods has the potential to increase photochemical remineralization of terrestrial and marine organic matter and production of labile organic material that can be used by microbes. Determining the impact of solar radiation changes on warming, primary production, and photochemistry are all critical in assessing and predicting the effects of climate change on the marine carbon cycle. The measurement of these variables within and beneath the seasonal ice pack is challenging due to the limitations of ship based observations, but this can be resolved by using the autonomous WARM buoys deployed within the ice and designed to survive ice melt.