气候变化领域集成服务门户(CCPortal): New flood frequency estimates for the largest river in Norway based on the combination of short and long time series

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DOI	10.5194/hess-24-5595-2020
	New flood frequency estimates for the largest river in Norway based on the combination of short and long time series
	Engeland K.; Aano A.; Steffensen I.; Støren E.; Paasche O.
发表日期	2020
ISSN	1027-5606
起始页码	5595
结束页码	5619
卷号	24 期号:11
英文摘要	The Glomma River is the largest in Norway, with a catchment area of 154 450 km2. People living near the shores of this river are frequently exposed to destructive floods that impair local cities and communities. Unfortunately, design flood predictions are hampered by uncertainty since the standard flood records are much shorter than the requested return period and the climate is also expected to change in the coming decades. Here we combine systematic historical and paleo information in an effort to improve flood frequency analysis and better understand potential linkages to both climate and non-climatic forcing. Specifically, we (i) compile historical flood data from the existing literature, (ii) produce high-resolution X-ray fluorescence (XRF), magnetic susceptibility (MS), and computed tomography (CT) scanning data from a sediment core covering the last 10 300 years, and (iii) integrate these data sets in order to better estimate design floods and assess non-stationarities. Based on observations from Lake Flyginnsjøen, receiving sediments from Glomma only when it reaches a certain threshold, we can estimate flood frequency in a moving window of 50 years across millennia revealing that past flood frequency is non-stationary on different timescales. We observe that periods with increased flood activity (4000 2000 years ago and 1 1000 years ago) correspond broadly to intervals with lower than average summer temperatures and glacier growth, whereas intervals with higher than average summer temperatures and receding glaciers overlap with periods of reduced numbers of floods (10 000 to 4000 years ago and 2200 to 1000 years ago). The flood frequency shows significant non-stationarities within periods with increased flood activity, as was the case for the 18th century, including the 1789 CE ("Stor-Ofsen") flood, the largest on record for the last 10 300 years at this site. Using the identified nonstationarities in the paleoflood record allowed us to estimate non-stationary design floods. In particular, we found that the design flood was 23% higher during the 18th century than today and that long-Term trends in flood variability are intrinsically linked to the availability of snow in late spring linking climate change to adjustments in flood frequency. © 2020 Georg Thieme Verlag. All rights reserved.
语种	英语
scopus关键词	Availability; Catchments; Climate change; Computerized tomography; Flood control; Magnetic susceptibility; Rivers; Sediments; Flood frequency; Flood frequency analysis; Historical floods; Long time series; Long-term trend; Non-stationarities; Summer temperature; X ray fluorescence; Floods; catchment; climate forcing; computer system; design flood; flood frequency; glacier advance; magnetic susceptibility; paleoflood; return period; sediment core; time series analysis; Glomma River; Norway
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159249
作者单位	Engeland, K., Norwegian Water Resources and Energy Directorate, Oslo, Norway; Aano, A., Norwegian Water Resources and Energy Directorate, Oslo, Norway, Department of Geosciences, University of Oslo, Oslo, Norway; Steffensen, I., Department of Earth Science, University of Bergen, Bergen, Norway; Støren, E., Department of Earth Science, University of Bergen, Bergen, Norway, Bjerknes Centre for Climate Research, Bergen, Norway; Paasche, O., Bjerknes Centre for Climate Research, Bergen, Norway, Norce Climate, Bergen, Norway
推荐引用方式 GB/T 7714	Engeland K.,Aano A.,Steffensen I.,et al. New flood frequency estimates for the largest river in Norway based on the combination of short and long time series[J],2020,24(11).
APA	Engeland K.,Aano A.,Steffensen I.,Støren E.,&Paasche O..(2020).New flood frequency estimates for the largest river in Norway based on the combination of short and long time series.Hydrology and Earth System Sciences,24(11).
MLA	Engeland K.,et al."New flood frequency estimates for the largest river in Norway based on the combination of short and long time series".Hydrology and Earth System Sciences 24.11(2020).