Comparison of PMP-Driven Probable Maximum Floods with Flood Magnitudes due to Increasingly Urbanized Catchment: The Case of American River Watershed

Abstract Since historical (predam) data are traditionally the sole criterion for dam design, future (postdam) meteorological and hydrological variability due to land-use and land-cover change cannot be considered for assessing design robustness. For example, postdam urbanization within a basin leads to definite and immediate increase in direct runoff and reservoir peak inflow. On the other hand, urbanization can strategically (i.e., gradually) alter the mesoscale circulation patterns leading to more extreme rainfall rates. Thus, there are two key pathways (immediate or strategic) by which the design flood magnitude can be compromised. The main objective of the study is to compare the relative contribution to increase in flood magnitudes through direct effects of land-cover change (urbanization and less infiltration) with gradual climate-based effects of land-cover change (modification in mesoscale storm systems). The comparison is cast in the form of a sensitivity study that looks into the response to the design probable maximum flood (PMF) from probable maximum precipitation (PMP). Using the American River watershed (ARW) and Folsom Dam as a case study, simulated peak floods for the 1997 (New Year's) flood event show that a 100% impervious watershed has the potential of generating a flood that is close to design PMF. On the other hand, the design PMP produces an additional 1500 m3 s−1 peak flood compared to the actual PMF when the watershed is considered 100% impervious. This study points to the radical need for consideration future land-cover changes up front during the dam design and operation formulation phase by considering not only the immediate effects but also the gradual climatic effects on PMF. A dynamic dam design procedure should be implemented that takes into account the change of land–atmospheric and hydrological processes as a result of land-cover modification rather than relying on historical records alone.

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ON THE USE OF FREQUENCY CURVES OF STORMFLOODS

Coastal Engineering Proceedings ◽

10.9753/icce.v7.33 ◽

2011 ◽

Vol 1 (7) ◽

pp. 33

Author(s):

P.J. Wemelsfelder

Keyword(s):

Coastal Engineering ◽

The Other ◽

Design Flood ◽

Economic Values ◽

Other Hand ◽

Two Factors ◽

Economic Nature ◽

Frequency Curves

In coastal engineering we often have to face the problem of high stormfloods. Especially if the land near the coast is flat and low, if it is densely populated or if high economic values have to be protected. In all these oases, where life and economic values are at stake, a design flood has to be established as a basis for the construction of the works of protection. Obviously the height of the design flood will be dependent on two factors. On one hand it depends on the characteristics of the sea, on its probable and possible heights. On the other hand it depends on the values of human and economic nature, threatened by the sea. So the design flood may be regarded as a balance between the threatening force of the sea and the values at stake. In this paper we will investigate the nature of this balance. This will lead us to a close examination of the frequency curves of stormfloods, to a discussion of the question: What is a reasonable risk and to a discussion of the question: What is the space of time we have to take into account.

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High Temporal Resolution Land Use/Land Cover Change from 1984 to 2010 of the Little River Watershed, Tennessee, Investigated Using Landsat and Google Earth Images

Southeastern Geographer ◽

10.1353/sgo.2013.0025 ◽

2013 ◽

Vol 53 (3) ◽

pp. 250-266 ◽

Cited By ~ 1

Author(s):

Chunhao Zhu ◽

Yingkui Li

Keyword(s):

Land Use ◽

Land Cover ◽

Land Cover Change ◽

Temporal Resolution ◽

Google Earth ◽

High Temporal Resolution ◽

Land Use Land Cover ◽

River Watershed

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Erosion risk assessment and identification of susceptibility lands using the ICONA model and RS and GIS techniques

10.5194/nhess-2020-85 ◽

2020 ◽

Author(s):

Hossein Esmaeili Gholzom ◽

Hassan Ahmadi ◽

Abolfazl Moeini ◽

Baharak Motamed Vaziri

Keyword(s):

Land Cover ◽

Catchment Area ◽

The Other ◽

Rock Outcrops ◽

Risk Class ◽

Erosion Risk ◽

Gis Techniques ◽

Rs And Gis ◽

Other Hand ◽

Very High

Abstract. Soil erosion in Iran due to the destruction of natural resources has intensified in recent years and land use changes have played a significant role in this process. On the other hand, the lack of data in most watersheds to evaluate erosion and sedimentation for finding quick and timely solutions for watershed management has made the use of models inevitable. The purpose of this study was to use the ICONA model and RS and GIS techniques to assess the risk of erosion and to identify areas sensitive to water erosion in the kasilian watershed in northern Iran. The results of this study showed that with very high slope class percentage (20 %–35 %) and sensitivity of shemshak formation to weathering which covers a large part of the watershed, soil erodibility class is high. But there is adequate land cover along with high percentage of natural forest cover, it has mitigated erosion. For this reason, the kasilian watershed is generally classified as low to moderate of erosion risk. Based on the erosion risk map, results show that the moderate class had the highest percentage of erosion risk (26.26 %) at the watershed. On the other hand, the low erosion risk class comprises a significant portion (25.44 %) of the catchment area. Also, 10.92 % of the catchment area contains a very high erosion risk class, with most of it in rangeland and Rock outcrops second. However, the erodibility of the kasilian watershed is currently controlled by appropriate land cover, but the potential susceptibility to erosion is high. If land cover is redused due to inadequate land management, the risk of erosion is easily increased.

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Riparian land-use and land cover change analysis using GIS in Pinang river watershed, Malaysia

Tropics ◽

10.3759/tropics.13.235 ◽

2004 ◽

Vol 13 (4) ◽

pp. 235-248 ◽

Cited By ~ 3

Author(s):

Ahmad Jailani Muhamed YUNUS ◽

Nobukazu NAKAGOSHI ◽

Ab Latif IBRAHIM

Keyword(s):

Land Use ◽

Land Cover ◽

Land Cover Change ◽

Change Analysis ◽

River Watershed ◽

Land Cover Change Analysis

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A DECADAL ANALYSIS AND SENSITIVITY STUDY USING MOPITT CO COLUMNS OVER ASIA

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-w5-53-2018 ◽

2018 ◽

Vol XLII-3/W5 ◽

pp. 53-59 ◽

Cited By ~ 1

Author(s):

C. Lin ◽

J. Cohen

Keyword(s):

Standard Deviation ◽

Biomass Burning ◽

Urban Areas ◽

Sensitivity Study ◽

The Other ◽

Peak Time ◽

Urban Regions ◽

Forest Clearing ◽

Other Hand ◽

A New Technique

Abstract. Biomass burning and urbanization are both significant sources of CO emissions and atmospheric loadings in the real environment. The sources of CO are due to incomplete combustion, on one hand of biomass from agriculture or forest clearing, and on the other hand from coal, oil, gas, and other similar materials. However, the spatial and temporal underlying properties and patterns are quite different between these two types of source regions, with urban regions having a relatively constant source of CO emissions, with only short term concentration fluctuations due to local meteorology. On the other hand, in biomass burning regions, the emissions themselves tend to be highly concentrated over a short burning period, and very low otherwise. We hence present a new technique to classify and quantify biomass burning regions and urban regions based on an objective analysis of the CO total column measurements from the MOPITT satellite. By using all of the data from 2000&ndash;2016, in connection with averages and standard deviation cutoffs, we successfully determine these regions. By performing a sensitivity analysis, in connection with additional ground-based measurements, we determine that the ideal cutoffs for the mean column loading and standard deviation of the column loading 28&times;1017mol/cm2 and 6&times;1017mol/cm2 respectively. These results are capable of representing known urban regions and biomass burning regions well throughout China, Southeast Asia, and South Asia, specifically including Beijing, Hebei, Shandong, Jiangsu, Anhui, Hunan, Guangdong, and Bangkok on one hand, and Northeastern India, Myanmar, Laos, Northern Thailand, and Vietnam on the other hand. A detailed analysis of the time series over the different classified regions show that while the urban areas have a much higher annual value, and a relatively long peak time, that their maximum is never as high as the peaks in the biomass burning regions, and that these peaks in the biomass burning regions are extremely short in duration, although they occur annually or bi-annually. Finally, we have not been able to obtain a statistically relevant decreasing trend, as others have found, making CO possibly an interesting species for future studies.

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