EAR-PF: Monitoring the role of subsurface physical processes in carbon flux from a degraded permafrost site using novel multidisciplinary observations

Stephanie R. James博士获得了美国国家科学基金会EAR博士后奖学金，在美国地质调查局，位于科罗拉多州丹佛的地壳地球物理和地球化学科学中心开展一项研究和教育计划。她的研究项目将提高对北极北方泥炭地如何在物理和化学上对融化的永久冻土作出反应的理解。永久冻土碳的释放有可能影响全球碳收支。然而，由于地表和地下过程之间的复杂关系、剧烈的季节变化以及地下测量能力的限制，这种影响的程度尚不确定。詹姆斯博士将在阿拉斯加费尔班克斯附近的多学科实地实验中使用地球物理和生物地球化学技术的新组合，以提高对现场尺度上碳通量的物理控制的理解。这将有助于在全球尺度上改进气候模型对永久冻土碳反馈的预测。此外，该项目将推进一种能够持续监测永久冻土退化的被动地震技术，这可以改善当地社区的基础设施安全。詹姆斯博士还将实施一项教育计划，以推进学术和专业科学探究和公共教育。为期多日的地球物理研讨会将对大学毕业生和专业人员进行前沿水文地球物理方法的培训。然后，对科罗拉多州丹佛市和阿肯色州费尔班克斯市的中学进行一系列地球科学外展访问，将扩大学生的意识并鼓励科学参与。该项目需要进行为期一年的多学科实地实验，并使用SUTRA 3.0代码将实地数据与水和能量传输的数值模拟相结合。被动地震、核磁共振、温度、土壤湿度和碳通量测量将沿着完整的永久冻土和塌陷疤痕沼泽之间的样带收集。通过使用地球物理和生物地球化学方法的独特组合，该项目将研究地下物理过程，如季节性冻融动力学和含水量变化，如何影响永久冻土融化梯度与大气的碳交换。数值模拟将提高对地表条件和地下过程之间关系的理解，并有助于解释地震速度变化。这项工作建立在阿拉斯加泥炭地实验（APEX）之前的研究基础上，并将推进永久冻土监测的被动地震技术。

Dr. Stephanie R. James has been awarded an NSF EAR Postdoctoral Fellowship to carry out a research and education plan at the U.S. Geological Survey, Crustal Geophysics and Geochemistry Science Center, in Denver, CO. Her research project will improve the understanding of how Arctic boreal peatlands respond, both physically and chemically, to thawing permafrost. The release of permafrost carbon has the potential to impact the global carbon budget. However, the magnitude of this impact is uncertain due to the complex relationships between processes above and below ground, dramatic seasonal changes, and limitations in subsurface measurement capabilities. Dr. James will use a novel combination of geophysical and biogeochemical techniques in a multidisciplinary field experiment near Fairbanks, Alaska to improve the understanding of the physical controls on carbon fluxes at the site scale. This will lead to improved predictions of the permafrost-carbon feedback in climate models at the global scale. In addition, this project will advance a passive seismic technique capable of continuous monitoring for permafrost degradation, which could improve infrastructure security in local communities. Dr. James will also conduct an education plan to advance academic and professional scientific inquiry and public education. A multiday geophysical workshop will train college graduates and professionals in cutting-edge hydrogeophysical methods. Then, a series of Earth science outreach visits to middle schools in Denver, CO and Fairbanks, AK will broaden student awareness and encourage science participation. This project entails a one year multidisciplinary field experiment and the integration of field data with numerical simulations of water and energy transport using the code SUTRA 3.0. Passive seismic, nuclear magnetic resonance, temperature, soil moisture, and carbon flux measurements will be collected along a transect between intact permafrost and a collapse-scar bog. By using a unique combination of geophysical and biogeochemical methods, this project will address how subsurface physical processes, such as seasonal freeze-thaw dynamics and changes in water content, impact carbon exchange with the atmosphere across a permafrost thaw gradient. Numerical modeling will improve the understanding of relationships between surface conditions and subsurface processes, as well as aid with interpretation of seismic velocity changes. This work builds off previous studies of the Alaskan Peatland Experiment (APEX) and will advance passive seismic techniques for permafrost monitoring.