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

WARM浮标收集北极海冰下的光照、温度、盐度和浮游植物丰度的测量结果。北极冰层持续变薄，季节性范围不断缩小，导致穿透冰层并进入冰层下海洋的阳光量发生变化，对物理和生物环境产生影响。太阳光被冰下的海洋吸收会导致变暖，这可能导致冰加速融化，导致更多的阳光到达海洋。此外，水温升高也影响到生物体，影响北极适应物种的生存能力，并可能促进亚北极物种向北迁移。冰层变薄也增加了光合作用的光照，影响了浮游植物大量繁殖的时间。如果浮游植物生长发生在季节的早期，那么浮游动物，以它们为食的生物可能会错过浮游植物的生长，从而对整个北极食物网产生影响。该项目的目的是通过使用自主浮标进行观测，帮助确定冰下环境的变化情况，自主浮标克服了船基观测的局限性。事实证明，这些浮标非常坚固，可以存活大约一年，每小时提供观测数据，研究界和感兴趣的公众可以近实时地获得这些数据。这些浮标将于早春部署在博福特海西部，预计将向西漂过楚科奇大陆架。 该项目将继续WARM浮标倡议，改进现有设计，增加温度和光照测量的垂直分辨率，增加盐度测量，以便能够识别水团，并增加第二个荧光计，以识别下沉的浮游植物生物量。所收集的数据将提供一个完整季节周期内重要物理和地球化学性质的时间序列。它将使我们能够解决与更薄和更开放的冰层对太阳辐射吸收、海洋加热、远洋初级生产的物候和碳循环的影响有关的问题。事实证明，浮标非常坚固，可持续约一年，每小时提供观测，研究界和有关公众可在接近真实的时间内获得观测结果。这些浮标将于早春部署在博福特海西部，预计将向西漂过楚科奇大陆架。 北极的冰层就像一个屏障，控制着紫外线和可见光对水柱的影响。北极季节性冰层的持续变薄和减少，导致太阳辐射穿透北冰洋上部的时间和强度发生变化。海洋吸收太阳辐射的放大作用使表层变暖并分层，这可能导致冰进一步退缩并延迟冻结。由此产生的热分层影响生态系统，限制垂直补充的营养物质，直接后果的规模上的初级生产。更温暖的水柱也可在确定浮游生物群落的丰度和分布阈值、影响营养效率和促进北极次区域物种向北迁移方面发挥重要作用。较薄的冰层增加了光合作用和净初级生产的光照，影响了初级生产的时间。浮游植物大量繁殖和浮游动物繁殖周期之间的微小时间不匹配可能对整个由脂质驱动的北极海洋生态系统产生影响。由于开放水域时间延长，紫外线照射时间的变化有可能增加陆地和海洋有机物的光化学矿化作用，并增加可被微生物利用的不稳定有机物质的产生。确定太阳辐射变化对变暖、初级生产和光化学的影响，对于评估和预测气候变化对海洋碳循环的影响至关重要。由于基于船舶的观测的限制，在季节性冰层内部和下方测量这些变量是具有挑战性的，但这可以通过使用部署在冰内的自主WARM浮标来解决，该浮标旨在在冰融化后生存。

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.