scholarly journals Evaluation of Future Flood Risk According to RCP Scenarios Using a Regional Flood Frequency Analysis for Ungauged Watersheds

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 992 ◽  
Author(s):  
Nam Won Kim ◽  
Jin-Young Lee ◽  
Dong-Hyeok Park ◽  
Tae-Woong Kim

According to the accepted climate change scenarios, the future rainfall in the Korean peninsula is expected to increase by 3–10%. The expected increase in rainfall leads to an increase of runoff that is directly linked to the stability of existing and newly installed hydraulic structures. It is necessary to accurately estimate the future frequency and severity of floods, considering increasing rainfall according to different climate change scenarios. After collecting observed flood data over twenty years in 12 watersheds, we developed a regional frequency analysis (RFA) for ungauged watersheds by adjusting flood quantiles calculated by a design rainfall-runoff analysis (DRRA) using natural flow data as an index flood. The proposed RFA was applied to estimate design floods and flood risks in 113 medium-sized basins in South Korea according to representative concentration pathway (RCP) scenarios. Regarding the future of the Korean peninsula, compared with the present, the flood risks were expected to increase by 24.85% and 20.28% on average for the RCP 8.5 and 4.5 scenarios, respectively.

OENO One ◽  
2018 ◽  
Vol 52 (1) ◽  
Author(s):  
Maria Concepción Ramos ◽  
Gregory V Jones ◽  
Jesús Yuste

Aim: This research examined relationships between grapevine phenology and climate in the Ribera del Duero DO (Spain). The observed varieties included Tempranillo, the main variety planted in the region, and Cabernet-Sauvignon.Methods and Results: Phenological events for stages C (budbreak), I (bloom), M (véraison) and N (maturity) were analyzed for 2004-2015. Dormant period chilling and late winter heating requirements to initiate growth were evaluated and accumulated temperature (growing degree days-GDD) prior to each phenological event and in between events were examined for the role they play in influencing growth timing. The results were then used to examine future phenological changes due to climate change using eight models integrated in the Coupled Model Intercomparison Project (CMIP5) and for two Representative Concentration Pathways (RCP) scenarios – RCP4.5 and RCP8.5 – for 2030, 2050, and 2070. Accumulated temperatures after March 20th become important for initiating phenology and are strongly correlated to all growth events. The influence of water availability between budbreak and bloom and between bloom and véraison on phenological timing was also confirmed.Conclusions: The projections showed that for the RCP4.5 emission scenario, budbreak is predicted earlier by approximately 2 days for 2030, 3 days for 2050 and 5 days for 2070, while bloom is predicted to be 3 to 8 days earlier and véraison 6 to 19 days earlier for the same time periods. For the RCP8.5 emission scenario, budbreak is modeled to take place about 3 days, 5 days and 9 days earlier, respectively for 2030, 2050 and 2070. Bloom is predicted to occur about 5, 10 and 16 days earlier; véraison is predicted earlier by 10 days for 2030, 19 days for 2050, and 28 days for 2070. Maturity and the timing of harvest could be up to 23 days earlier under the RCP4.5 emission scenario and up to 35 days earlier under the RCP8.5 emission scenario. Compared to Cabernet-Sauvignon, Tempranillo exhibited greater phenological sensitivity to temperature changes in the observed time period that is likely to continue into the future with greater changes to earlier growth events projected. This sensitivity could be problematic for the region due to the variety’s historic importance and points to the need to examine adaptive measures that can help growers to respond to projected changes in climate.Significance and impact of the study: The projected climate changes in the future indicate the potential for significant changes in the phenology of Tempranillo in the Ribera del Duero DO, Spain. Given that this variety has the largest contribution and importance in this region, these changes could have impacts on wine quality, indicating the need of establishing strategies to reduce or mitigate the impact from future changes in climate.


Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2052 ◽  
Author(s):  
Kim ◽  
Yoo ◽  
Chung ◽  
Kim

Recently, climate change has increased the frequency of extreme weather events. In South Korea, extreme droughts are frequent and cause serious damage. To identify the risk of extreme drought, we need to calculate the hydrologic risk using probabilistic analysis methods. In particular, future hydrologic risk of extreme drought should be compared to that of the control period. Therefore, this study quantitatively assessed the future hydrologic risk of extreme drought in South Korea according to climate change scenarios based on the representative concentration pathway (RCP) 8.5. A threshold level method was applied to observation-based rainfall data and climate change scenario-based future rainfall data to identify drought events and extract drought characteristics. A bivariate frequency analysis was then performed to estimate the return period considering both duration and severity. The estimated return periods were used to calculate and compare hydrologic risks between the control period and the future. Results indicate that the average duration of drought events for the future was similar with that for the control period, however, the average severity increased in most future scenarios. In addition, there was decreased risk of maximum drought events in the Yeongsan River basin in the future, while there was increased risk in the Nakdong River basin. The median of risk of extreme drought in the future was calculated to be larger than that of the maximum drought in the control period.


Water ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 270 ◽  
Author(s):  
Minsung Kwon ◽  
Jang Sung ◽  
Jaehyun Ahn

Although the magnitude and frequency of extreme events on the global scale are expected to change because of changes in the hydrological cycle under climate change, little quantitative assessment of future extreme precipitation in North Korea has been attempted. Therefore, this study projected the changes in extreme precipitation in North Korea by applying downscaling to GCMs forced by Representative Concentration Pathway (RCP) Scenarios 4.5 and 8.5, preserving the long-term trend of climate change projection. Employing climate change scenario ensembles of RCP8.5, the precipitation level of the 20-year return period in the reference period of 1980–2005 increased to 21.1 years for the future period 2011–2040, decreased to 16.2 years for 2041–2070, and decreased to 8.8 years for 2071–2100. Extreme precipitation was expected to occur often in the future. In addition, an increase in extreme precipitation at the border of North and South Korea is expected, and it is concluded that a joint response for the Imjin River, a river shared by North and South Korea, is needed.


2014 ◽  
Vol 15 (3) ◽  
pp. 1205-1219 ◽  
Author(s):  
X. S. Qin ◽  
Y. Lu

Abstract Climate change is expected to lead to more frequent and intensive flooding problems for watersheds in the south part of China. This study presented a coupled Long Ashton Research Station Weather Generator (LARS-WG) and Semidistributed Land Use–Based Runoff Processes (SLURP) approach for flood frequency analysis and applied it to the Heshui watershed, China. LARS-WG, as a weather generator, was used to offer 46 sets of climate data from seven general circulation models (GCMs) under various emission scenarios (i.e., A1B, B1, and A2) over near-term and future periods (i.e., T1, 2011–30; T2, 2046–65; and T3, 2080–99). SLURP is a continuous, spatially distributed hydrological model that uses parameters from physiographic data to simulate the hydrological cycle from precipitation to runoff. Flood frequency analysis based on Pearson type III distributions was followed to analyze statistics of annual peaks. The final results (from ensembles of multimodels and multiscenarios) indicated that the magnitudes of a 200-yr return flood for T1, T2, and T3 would increase by 5.23%, 4.08%, and 12.92%, respectively, in comparison to the baseline level; those under the most extreme condition (i.e., worst scenario) would be 25.18%, 31.00%, and 44.46%, respectively. Various GCMs and emission scenarios suggested different results. But the ECHAM5/Max Planck Institute Ocean Model was found to give a more worrying intensification of flood risks and the Commonwealth Scientific and Industrial Research Organisation Mark, version 3.0, and the Community Climate System Model, version 3, were relatively conservative. The study results were useful in helping gain insight into the flood risks and its uncertainty under future climate change conditions for the Heshui watershed, and the proposed methodology is also applicable to many other watersheds in Southeast Asia with similar climatic conditions.


2021 ◽  

Abstract This book is a collection of 77 expert opinions arranged in three sections. Section 1 on "Climate" sets the scene, including predictions of future climate change, how climate change affects ecosystems, and how to model projections of the spatial distribution of ticks and tick-borne infections under different climate change scenarios. Section 2 on "Ticks" focuses on ticks (although tick-borne pathogens creep in) and whether or not changes in climate affect the tick biosphere, from physiology to ecology. Section 3 on "Disease" focuses on the tick-host-pathogen biosphere, ranging from the triangle of tick-host-pathogen molecular interactions to disease ecology in various regions and ecosystems of the world. Each of these three sections ends with a synopsis that aims to give a brief overview of all the expert opinions within the section. The book concludes with Section 4 (Final Synopsis and Future Predictions). This synopsis attempts to summarize evidence provided by the experts of tangible impacts of climate change on ticks and tick-borne infections. In constructing their expert opinions, contributors give their views on what the future might hold. The final synopsis provides a snapshot of their expert thoughts on the future.


2021 ◽  
Author(s):  
Tim van der Schriek ◽  
Konstantinos V. Varotsos ◽  
Dimitra Founda ◽  
Christos Giannakopoulos

<p>Historical changes, spanning 1971–2016, in the Athens Urban Heat Island (UHI) over summer were assessed by contrasting two air temperature records from established meteorological stations in urban and rural settings. When contrasting two 20-year historical periods (1976–1995 and 1996–2015), there is a significant difference in summer UHI regimes. The stronger UHI-intensity of the second period (1996–2015) is likely linked to increased pollution and heat input. Observations suggest that the Athens summer UHI characteristics even fluctuate on multi-annual basis. Specifically, the reduction in air pollution during the Greek Economic Recession (2008-2016) probable subtly changed the UHI regime, through lowering the frequencies of extremely hot days (T<sub>max</sub> > 37 °C) and nights (T<sub>min</sub> > 26 °C).</p><p>Subsequently, we examined the future temporal trends of two different UHIs in Athens (Greece) under three climate change scenarios. A five-member regional climate model (RCM) sub-ensemble from EURO-CORDEX with a horizontal resolution of 0.11° (~12 × 12 km) simulated air temperature data, spanning the period 1976–2100, for the two station sites. Three future emissions scenarios (RCP2.6, RCP4.5 and RCP8.5) were implanted in the simulations after 2005. The observed daily maximum and minimum air temperature data (T<sub>max</sub> and T<sub>min</sub>) from two historical UHI regimes (1976–1995 and 1996–2015, respectively) were used, separately, to bias-adjust the model simulations thus creating two sets of results.</p><p>This novel approach allowed us to assess future temperature developments in Athens under two different UHI intensity regimes. We found that the future frequency of days with T<sub>max</sub> > 37 °C in Athens was only different from rural background values under the intense UHI regime. There is a large increase in the future frequency of nights with T<sub>min</sub> > 26 °C in Athens under all UHI regimes and climate scenarios; these events remain comparatively rare at the rural site.</p><p>This study shows a large urban amplification of the frequency of extremely hot days and nights which is likely forced by increasing air pollution and heat input. Consequently, local mitigation policies aimed at decreasing urban atmospheric pollution are expected to be also effective in reducing urban temperatures during extreme heat events in Athens under all future climate change scenarios. Such policies therefore have multiple benefits, including: reducing electricity (energy) needs, improving living quality and decreasing heat- and pollution related illnesses/deaths.</p><p> </p>


2016 ◽  
Vol 64 (3) ◽  
Author(s):  
David A. Moo-Llanes

The leishmaniasis is a complex disease system, caused by the protozoan parasite Leishmania and transmitted to humans by the vector Lutzomyia spp. Since it is listed as a neglected disease according to the World Health Organization, the aim of this study was to determine the current and future niche of cutaneous and visceral leishmaniasis in the Neotropical region. We built the ecological niche model (ENM) of cutaneous (N= 2 910 occurrences) and visceral (N= 851 occurrences) leishmaniasis using MaxEnt algorithm. Nine bioclimatic variables (BIO1, BIO4, BIO5, BIO6, BIO7, BIO12, BIO13, BIO14, BIO15 (downloaded from the Worldclim) and disease occurrences data were used for the construction of ENM for three periods (current, 2050 and 2070) and four climate change scenarios (RCP 2.6, 4.5, 6.0 y 8.5). We analyzed the number of pixels occupied, identity niche, modified niche (stable, loss, and gain) and seasonality. Our analyses indicated the expansion for cutaneous leishmaniasis (CL), a comparison for visceral leishmaniasis (VL). We rejected the null hypothesis of niche identity between CL and VL with Hellinger’s index = 0.91 (0.92-0.98) and Schoener’s Index = 0.67 (0.85-1.00) but with an overlap niche of 56.3 %. The differences between the two leishmaniasis types were detected in relation to RCP scenarios and niche shifts (area gained / loss). Seasonality was more important for CL. We provided a current picture of CL and VL distributions and the predicted distributional changes associated to different climate change scenarios for the Neotropical region. We can anticipate that increasing range is likely although it will depend locally on the future trends in weather seasonality.


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