Doctoral Dissertation Research: Another piece of the Arctic carbon puzzle: quantifying emissions from Arctic lakes in drier regions

湖泊是北极景观的主要特征，可能是大气中二氧化碳的重要来源，但大规模的北极碳预算通常忽略了湖泊的碳排放。此外，对北方湖泊碳排放的研究主要局限于湖泊与融化的永久冻土相连的地区。 位于干燥景观的湖泊的排放，其中约25%的北方永久冻土区，已相对研究不足。因此，目前还不确定位于干旱地区的湖泊在多大程度上导致了碳排放，这一问题可能会恶化，因为预计北极大部分地区未来将变得越来越温暖和干燥。 该项目解决了这两个关键差距。首先，研究人员正在使用自动传感器来测量西格陵兰湖的碳排放量，该地区正在经历快速变暖和降水量下降。 研究人员还将他们的湖泊排放测量结果与先前发表的观测结果相结合，以评估气候模式的差异如何影响湖泊和大气之间的二氧化碳通量。 这项研究的结果将在跨学科学术小组，科普杂志，青年科学计划中介绍，并与西格陵兰社区进行讨论。西格陵兰的Kangerlussuaq地区位于沿着水文气候梯度，是研究北极气候变暖和干燥对内陆沃茨碳动态影响的模型景观。研究人员正在量化一系列湖泊的碳排放量，这些湖泊沿着一个气候降水梯度，模拟全年从凉爽和潮湿的气候到干燥和温暖的气候变化，使用高频原位传感器。这些传感器提供了第一个年度的，时间上很好地解决了从湖泊中的二氧化碳排放量的测量水文连接不良，干旱的北极景观。研究人员正在将他们的测量结果扩大到区域水平，并将其与周围景观中的陆地碳通量进行比较。该研究突出了北极碳循环的异质性及其在整个北极系统中的作用。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。

Lakes are a dominant feature of the Arctic landscape and can be important sources of carbon dioxide to the atmosphere, but large-scale Arctic carbon budgets usually neglect carbon emissions from lakes. Moreover, studies of carbon emissions from northern lakes have largely been limited to regions where lakes are connected to thawing permafrost. Emissions from lakes located in drier landscapes, which cover about 25% of the northern permafrost region, have been relatively understudied. Consequently, it is uncertain to what degree lakes located in drier regions contribute to carbon emissions, a problem that likely will worsen as much of the Arctic is predicted to become warmer and drier in the future. This project addresses both critical gaps. First, the researchers are using automated sensors to measure carbon emissions from lakes in West Greenland, a region experiencing rapid warming and declining precipitation. The researchers are also synthesizing their lake emission measurements with previously published observations to assess how differences in climate patterns impact fluxes of carbon dioxide between lakes and the atmosphere. The results of this research will be presented in interdisciplinary academic panels, popular science magazines, youth science programs, and discussed with West Greenland communities. The Kangerlussuaq region in West Greenland located along a hydro-climatic gradient serves as a model landscape for studying the implications of warmer and drier Arctic conditions for carbon dynamics in inland waters. The researchers are quantifying carbon emissions from a suite of lakes along a climate-precipitation gradient that mimics shifts from cooler and wetter climate to drier and warmer conditions throughout the whole year, using high-frequency, in situ sensors. These sensors are providing the first annual, temporally well resolved measurements of carbon dioxide emissions from lakes in poorly hydrologically connected, arid Arctic landscapes. The researchers are upscaling their measurements to the regional level and comparing them with terrestrial carbon fluxes in the surrounding landscape. This research is highlighting the heterogeneity of the Arctic carbon cycle and its role in the full Arctic system.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.