CAREER: Coastal Antarctic Snow Algae and Light Absorbing Particles: Snowmelt, Climate and Ecosystem Impacts

职业：南极沿海雪藻和光吸收颗粒：融雪、气候和生态系统影响

• 批准号: 2046240
• 负责人: Alia Khan
• 金额: $ 122.84万
• 依托单位: Western Washington University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2027-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2046240&HistoricalAwards=false
• 关键词: CAREER; Coastal; Antarctic; Snow; Algae

________________________________________________________________________________________________Part I: Non-technical SummaryThe Antarctic Peninsula is one of the most rapidly warming regions on the planet. This 5-yr time-series program will build on an ongoing international collaboration with scientists from the Chilean Antarctic Program to evaluate the role of temperature, light absorbing particles, snow-algae growth, and their radiative forcing effects on snow and ice melt in the Western Antarctic Peninsula. There is strong evidence that these effects may be intensifying due to a warming climate. Rising temperatures can increase the growth rate of coastal snow algae as well as enhance the input of particles from sources such as the long-range transport of black carbon to the Antarctic continent from intensifying Southern Hemisphere wildfire seasons. Particle and algae feedbacks can have immediate local impacts on snow melt and long-term regional impacts on climate because reduced snow cover alters how the Antarctic continent interacts with the rest of the global climate. A variety of ground-based and remote sensing data collected across multiple spatial scales will be used. Ground measurements will be compared to satellite imagery to develop novel computer algorithms to map ice algal bloom effects under changing climates. The project is expected to fundamentally advance knowledge of the spatial and temporal snow algae growing season, which is needed to quantify impacts on regional snow and ice melt. The program also has a strong partnership with the International Association of Antarctic Tour Operators to involve cruise passengers as citizen scientists for sample collection. Antarctic research results will be integrated into undergraduate curricula and research opportunities through studies to LAPs and snow algae in the Pacific Northwest. The PI will recruit and train a diverse pool of students in cryosphere climate related research methods on Mt. Baker in Western Washington. Trained undergraduate will then serve as instructors for a local Snow School that takes middle school students to Mt. Baker to learn about snow science. Resulting datasets from Antarctica and Mt. Baker will be used in University classes to explore regional effects of climate change. Along with enhancing cryosphere-oriented place-based undergraduate field courses in the Pacific Northwest, the PI will recruit and train a diverse pool of undergraduate students to serve as instructors for the Mt. Baker Snow School program. This award will advance our understanding of cryosphere-climate feedbacks, which are likely changing and will continue to evolve in a warming world, while also increasing under-represented student engagement in the polar geosciences. Part 2: Technical Summary Rapid and persistent climate warming in the Western Antarctic Peninsula is likely resulting in intensified snow-algae growth and an extended bloom season in coastal areas. Similarly, deposition of light absorbing particles (LAPs) onto Antarctica cryosphere surfaces, such as black carbon from intensifying Southern Hemisphere wildfire seasons, and dust from the expansion of ice-free regions in the Antarctic Peninsula, may be increasing. The presence of snow algae blooms and LAPs enhance the absorption of solar radiation by snow and ice surfaces. This positive feedback creates a measurable radiative forcing, which can have immediate local and long-term regional impacts on albedo, snow melt and downstream ecosystems. This project will investigate the spatial and temporal distribution of snow algae, black carbon and dust across the Western Antarctica Peninsula region, their response to climate warming, and their role in regional snow and ice melt. Data will be collected across multiple spatial scales from in situ field measurements and sample collection to imagery from ground-based photos and high resolution multi-spectral satellite sensors. Ground measurements will inform development and application of novel algorithms to map algal bloom extent through time using 0.5-3m spatial resolution multi-spectral satellite imagery. Results will be used to improve snow algae parameterization in a new version of the Snow Ice Aerosol Radiation model (SNICARv3) that includes bio-albedo feedbacks, eventually informing models of ice-free area expansion through incorporation of SNICARv3 in the Community Earth System Model. Citizen scientists will be mentored and engaged in the research through an active partnership with the International Association of Antarctic Tour Operators that frequently visits the region. The cruise ship association will facilitate sampling to develop a unique snow algae observing network to validate remote sensing algorithms that map snow algae with high-resolution multi-spectral satellite imagery from space. These time-series will inform instantaneous and interannual radiative forcing calculations to assess impacts of snow algae and LAPs on regional snow melt. Quantifying the spatio-temporal growing season of snow algae and impacts from black carbon and dust will increase our ability to model their impact on snow melt, regional climate warming and ice-free expansion in the Antarctic Peninsula region.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

第一部分：非技术性摘要南极半岛是地球上变暖最快的地区之一。这个为期5年的时间序列计划将建立在与智利南极计划科学家正在进行的国际合作的基础上，以评估温度，光吸收颗粒，雪藻生长的作用，以及它们对南极西部半岛冰雪融化的辐射强迫效应。有强有力的证据表明，由于气候变暖，这些影响可能正在加剧。气温上升可以增加沿海雪藻的生长速度，并增加来自黑碳从南半球野火季节加剧到南极大陆的远距离运输等来源的颗粒输入。颗粒和藻类的反馈可以对雪融化产生直接的局部影响，并对气候产生长期的区域影响，因为积雪减少改变了南极大陆与全球其他地区气候的相互作用。将使用在多个空间尺度上收集的各种地面和遥感数据。地面测量结果将与卫星图像进行比较，以开发新的计算机算法，绘制气候变化下冰藻水华的影响。预计该项目将从根本上推进对雪藻生长季节的时空知识，这是量化对区域冰雪融化影响所必需的。该计划还与国际南极旅行社协会建立了强有力的合作伙伴关系，让游轮乘客作为公民科学家参与样本收集。南极研究成果将通过对太平洋西北地区的LAPs和雪藻的研究纳入本科课程和研究机会。PI将招募和培训不同的学生在冰冻圈气候相关的研究方法对山。华盛顿西部的贝克。受过训练的本科生将担任当地雪学校的教师，该学校将中学生带到山上。了解雪的科学知识。来自南极洲和Mt.的结果数据集贝克将用于大学课程，以探索气候变化的区域影响。沿着在太平洋西北部加强以冰冻圈为导向的地方为基础的本科生实地课程，PI将招募和培训一批多样化的本科生，担任山导师。贝克斯诺学校项目。该奖项将促进我们对冰冻圈气候反馈的理解，这些反馈可能会发生变化，并将在变暖的世界中继续演变，同时也增加了极地地球科学中代表性不足的学生参与。第二部分：南极半岛西部气候迅速和持续变暖可能导致沿海地区雪藻生长加剧和水华季节延长。同样，南极冰冻圈表面的吸光颗粒沉积，如南半球野火季节加剧产生的黑碳，以及南极半岛无冰区扩张产生的尘埃，可能正在增加。雪藻水华和LAPs的存在增强了雪和冰表面对太阳辐射的吸收。这种积极的反馈产生了可测量的辐射强迫，这可能对干旱、积雪融化和下游生态系统产生直接的地方和长期的区域影响。该项目将调查南极洲西部半岛地区雪藻、黑碳和尘埃的时空分布，它们对气候变暖的反应，以及它们在区域冰雪融化中的作用。将在多个空间尺度上收集数据，从实地测量和样本收集到地面照片和高分辨率多光谱卫星传感器的图像。地面测量将为开发和应用新的算法提供信息，以便使用0.5- 3米空间分辨率的多光谱卫星图像绘制藻类水华的时间范围。结果将用于改进新版本的雪冰气溶胶辐射模型（SNICARv 3）中的雪藻参数化，该模型包括生物反馈，最终通过将SNICARv 3纳入社区地球系统模型，为无冰区扩展模型提供信息。公民科学家将通过与经常访问该地区的国际南极旅游经营者协会建立积极的伙伴关系，接受指导并参与研究。游轮协会将协助取样，以开发一个独特的雪藻观测网络，验证利用空间高分辨率多光谱卫星图像绘制雪藻图的遥感算法。这些时间序列将为瞬时和年际辐射强迫计算提供信息，以评估雪藻和LAPs对区域积雪融化的影响。量化雪藻的时空生长季节以及黑碳和灰尘的影响将提高我们模拟雪融、区域气候变暖和南极半岛地区无冰扩张影响的能力。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Albedo change from snow algae blooms can contribute substantially to snow melt in the North Cascades, USA

• DOI: 10.1038/s43247-023-00768-8
• 发表时间: 2023-05-08
• 期刊: COMMUNICATIONS EARTH & ENVIRONMENT
• 影响因子: 7.9
• 作者: Healy, Shannon M. M.;Khan, Alia L. L.
• 通讯作者: Khan, Alia L. L.