Collaborative Research: RAPID: Typhoon Merbok in coastal western Alaska: Extent of flooding and impacts on plant communities and ecosystem function

合作研究：RAPID：阿拉斯加西部沿海的台风梅尔博克：洪水的程度及其对植物群落和生态系统功能的影响

• 批准号: 2302107
• 负责人: Katharine Kelsey
• 金额: $ 4.18万
• 依托单位: University of Colorado at Denver-Downtown Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-12-01 至 2024-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2302107&HistoricalAwards=false
• 关键词: Collaborative; Research; RAPID; Typhoon; Merbok

On September 16th, 2022, the Yukon-Kuskokwim (YK) Delta of western Alaska was hit by ex-Typhoon Merbok, a storm that many residents of the area described as the worst in their lifetime. The storm surge was several meters in height, and inland locations that normally do not flood under the highest tides of the year were inundated, resulting in extensive loss of homes, fishing boats, and subsistence cabins. This storm was unusual not only because of its size, but also its timing as the ground was not yet frozen or snow-covered. Since the Delta is flat, salty water extended for about a dozen or more miles inland, flooding Alaskan villages, hunting and fishing camps, and landscapes that are not acclimated to frequent floods. In this work, scientists will perform aerial and ground surveys to map the extent of the floods by looking for driftwood and other vegetation left behind by retreating water. Where driftwood is found, scientists will determine the amount of sediment deposited and measure pond salinity to test whether ponds switched from freshwater to salty water during the flood. The researchers will then set-up areas to observe longer-term effects of the floods on plants and the release of greenhouse gases to the atmosphere. As climate change contributes to larger and more frequent storms like Typhoon Merbok, understanding the consequences of them is becoming increasingly important to better prepare for the impacts of these storms on the landscape and the people who live in their path. This research consists of three components to address the extent and impact of Typhoon Merbok on the YK Delta region. First, researchers will conduct aerial and river surveys of drift lines and salinity along four rivers near Chevak, Alaska. For aerial surveys, transects ca. 30 km long and 2 km apart will be flown in mid-autumn 2022 with two observers photographing drift lines. All photographs will be geolocated. For river surveys, researchers will locate and sample debris, collect soil to quantity sediment deposition, and sample water bodies for salinity. Second, researchers will use high-resolution remotely-sensed imagery to locate fields of larger debris over a greater extent of the YK Delta. The elevation of debris from components one and two will be extracted from available LIDAR and structure-from-motion elevation models to determine the elevation of flood waters. Finally, researchers will establish monitoring plots to test hypotheses about impacts of the flooding, including evaluating changes to plant community composition, CO2 flux due to salt-kill, and CH4 flux due to suppression of methanogenesis by sulfates that occur in sea water. The project will produce valuable maps and data on the impacts of Merbok on the YK Delta Region, which will be made publicly available and be shared directly with local communities.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.

2022年9月16日，阿拉斯加西部的Yukon-Kuskokwim（YK）Delta遭到了前泰顿Merbok的袭击，前泰顿Merbok袭击了该地区的许多居民一生中最糟糕的居民。风暴潮的高度数米，通常不会在一年中最高潮流下洪水泛滥的内陆地点被淹没，导致房屋，渔船和自给自足的小木屋造成了广泛的损失。这场风暴不仅是因为它的大小，而且是因为地面尚未冻结或雪覆盖的时机。由于三角洲是平坦的，因此咸水延伸了大约十二英里或更多的内陆，淹没了阿拉斯加村庄，狩猎和钓鱼营，以及不适应经常洪水的景观。在这项工作中，科学家将通过寻找漂流和其他植被通过撤退来进行空中调查，以绘制洪水的程度。在发现浮木的地方，科学家将确定沉积的沉积物量，并测量池塘盐度，以测试池塘在洪水期间是否从淡水转为咸水。然后，研究人员将建立区域，以观察洪水对植物的长期影响，并向大气中释放温室气体。随着气候变化有助于更大，更频繁的风暴，例如台风Merbok，了解它们的后果变得越来越重要，以便更好地准备这些风暴对景观的影响以及生活在其道路上的人们。这项研究包括三个组成部分，以解决台风Merbok对YK三角洲地区的范围和影响。首先，研究人员将对阿拉斯加雪瓦克附近的四条河流进行漂移线和盐度的空中调查。对于空中调查，横断面大约。 30公里长，相距2公里，将在2022年中旬驾驶，有两个观察员拍摄漂移线。所有照片都将被挖掘。对于河流调查，研究人员将找到和采样碎屑，收集土壤到数量沉积物沉积，并采样水体以盐度。其次，研究人员将使用高分辨率的远程图像在更大程度上YK Delta中定位较大碎片的田地。将从可用的激光雷达和结构升高模型中提取碎片的碎屑升高，以确定洪水的升高。最后，研究人员将建立监测图，以测试有关洪水影响的假设，包括评估植物群落组成的变化，由于盐杀性而引起的二氧化碳通量以及由于海水中硫酸盐抑制甲基生成而引起的CH4通量。该项目将生成有关Merbok对YK Delta地区影响的有价值的地图和数据，该项目将公开可用，并直接与当地社区共享。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的审查标准通过评估来通过评估来支持的。