scholarly journals A comparison between direct and indirect frameworks to evaluate impacts of climate change on streamflows: case study of Karkheh River basin in Iran

2017 ◽  
Vol 8 (4) ◽  
pp. 652-674 ◽  
Author(s):  
Mohsen Nasseri ◽  
Banafsheh Zahraie ◽  
Leila Forouhar

Abstract In this paper, two approaches to assess the impacts of climate change on streamflows have been used. In the first approach (direct), a statistical downscaling technique was utilized to predict future streamflows based on large-scale data of general circulation models (GCMs). In the second approach (indirect), GCM outputs were downscaled to produce local climate conditions which were then used as inputs to a hydrological simulation model. In this article, some data-mining methods such as model-tree, multivariate adaptive regression splines and group method of data handling were utilized for direct downscaling of streamflows. Projections of HadCM3 model for A2 and B2 SRES scenarios were also used to simulate future climate conditions. These evaluations were done over three sub-basins of Karkheh River basin in southwest Iran. To achieve a comprehensive assessment, a global uncertainty assessment method was used to evaluate the results of the models. The results indicated that despite simplifications included in the direct downscaling, this approach is accurate enough to be used for assessing climate change impacts on streamflows without computational efforts of hydrological modeling. Furthermore, comparing future climate projections, the uncertainty associated with elimination of hydrological modeling is estimated to be high.

2012 ◽  
Vol 32 ◽  
pp. 99-107 ◽  
Author(s):  
J. Korck ◽  
J. Danneberg ◽  
W. Willems

Abstract. The Inn River basin is a highly relevant study region in terms of potential hydrological impacts of climate change and cross boundary water management tasks in the Alpine Space. Regional analyses in this catchment were performed within the EU co-funded project AdaptAlp. Objective of the study was to gain scientifically based knowledge about impacts of climate change on the water balance and runoff regime for the Inn River basin, this being fundamental for the derivation of adaptation measures. An ensemble of regional climate projections is formed by combinations of global and regional climate models on the basis of both statistical and bias-corrected dynamical downscaling procedures. Several available reference climate datasets for the study region are taken into account. As impact model, the process-oriented hydrological model WaSiM-ETH is set up. As expected, regional climate projections indicate temperature increases for the future in the study area. Projections of precipitation change are less homogenous, especially regarding winter months, though most indicate a decrease in the summer. Hydrological simulation results point towards climate induced changes in the water regime of the study region. The analysis of hydrological projections at both ends of the ensemble bandwidth is a source of adaptation relevant information regarding low-flow and high-flow conditions. According to a "drought-prone scenario", mean monthly low flow could decrease up to −40% in the time frame of 2071–2100. A "high-flow-increase-scenario" points towards an increase in mean monthly high flow in the order of +50% in the winter, whilst showing a decrease in autumn.


2021 ◽  
Vol 13 (7) ◽  
pp. 3885
Author(s):  
Christos Spyrou ◽  
Michael Loupis ◽  
Νikos Charizopoulos ◽  
Ilektra Apostolidou ◽  
Angeliki Mentzafou ◽  
...  

Nature-based solutions (NBS) are being deployed around the world in order to address hydrometeorological hazards, including flooding, droughts, landslides and many others. The term refers to techniques inspired, supported and copied from nature, avoiding large constructions and other harmful interventions. In this work the development and evaluation of an NBS applied to the Spercheios river basin in Central Greece is presented. The river is susceptible to heavy rainfall and bank overflow, therefore the intervention selected is a natural water retention measure that aims to moderate the impact of flooding and drought in the area. After the deployment of the NBS, we examine the benefits under current and future climate conditions, using various climate change scenarios. Even though the NBS deployed is small compared to the rest of the river, its presence leads to a decrease in the maximum depth of flooding, maximum velocity and smaller flooded areas. Regarding the subsurface/groundwater storage under current and future climate change and weather conditions, the NBS construction seems to favor long-term groundwater recharge.


2020 ◽  
Author(s):  
Koen De Ridder ◽  
Filip Lefebre ◽  
Eline Vanuytrecht ◽  
Julie Berckmans ◽  
Hendrik Wouters

<p>Biodiversity is increasingly under pressure from climate change, which affects the habitat suitability for species as well as the efficiency of ecosystem services. Management of these issues, for instance through ecosystem restoration or species dispersal measures, is often hindered by a lack of appropriate information about (future) climate conditions.  To address this, an operational Sectoral Information System (SIS) for the Biodiversity sector (SIS Biodiversity) is designed within the Copernicus programme Climate Change Service (C3S). This new SIS provides tailored bio-climatic indicators and applications, and delivers novel evidence regarding impacts of past, present and future climate. As such, it provides support to decision making challenges that are currently facing unmet climate data needs.<br> <br>The new climate service for SIS Biodiversity will be demonstrated, including the outline, workflow and outcomes of the use cases. The service is built upon the Copernicus Data Store platform (CDS; ), and takes into account (1) the barriers in ongoing bio-climate assessments and (2) the user requirements of diverse stakeholders (e.g. researcher institutes, local NGO’s, the International Union for Conservation of Nature and Natural Resources (IUCN),…). These have been collected during workshops and bilateral meetings in 2019. A common barrier is the lack of reliable and high-resolution information about states and dynamics of the soil, sea, ice and air for the past and the future climate. Therefore, the service provides relevant bio-climatic indicators on the basis of a wealth of available variables from the latest ERA5 reanalysis datasets and the CMIP5 global climate projections available in CDS. In order to provide information at high resolution and minimize inconsistencies between observed and modelled variables, different downscaling and bias-correction techniques are applied. A common requirement is a universal and flexible interface to the bio-climatic indicators in an easy-to-use and coherent platform that is applicable for different fauna and flora species of interest. Therefore, different applications have been developed within CDS for generating bio-climate suitability envelopes from the high-resolution indicators and to evaluate climate suitability and impacts for the species under present and future climate. Finally, the service is currently tested and refined on the basis of specific use cases. Special attention is given to their transferability to other global and topical studies, hence maximizing external user uptake throughout existing research and policy networks.</p>


2019 ◽  
Vol 42 (3) ◽  
pp. 987-1000 ◽  
Author(s):  
Dongli Fan ◽  
Honglin Zhong ◽  
Biao Hu ◽  
Zhan Tian ◽  
Laixiang Sun ◽  
...  

Abstract Chinese Medicinal Yam (CMY) has been prescribed as medicinal food for thousand years in China by Traditional Chinese Medicine (TCM) practitioners. Its medical benefits include nourishing the stomach and spleen to improve digestion, replenishing lung and kidney, etc., according to the TCM literature. As living standard rises and public health awareness improves in recent years, the potential medicinal benefits of CMY have attracted increasing attention in China. It has been found that the observed climate change in last several decades, together with the change in economic structure, has driven significant shift in the pattern of the traditional CMY planting areas. To identify suitable planting area for CMY in the near future is critical for ensuring the quality and supply quantity of CMY, guiding the layout of CMY industry, and safeguarding the sustainable development of CMY resources for public health. In this study, we first collect 30-year records of CMY varieties and their corresponding phenology and agro-meteorological observations. We then consolidate these data and use them to enrich and update the eco-physiological parameters of CMY in the agro-ecological zone (AEZ) model. The updated CMY varieties and AEZ model are validated using the historical planting area and production under observed climate conditions. After the successful validation, we use the updated AEZ model to simulate the potential yield of CMY and identify the suitable planting regions under future climate projections in China. This study shows that regions with high ecological similarity to the genuine and core producing areas of CMY mainly distribute in eastern Henan, southeastern Hebei, and western Shandong. The climate suitability of these areas will be improved due to global warming in the next 50 years, and therefore, they will continue to be the most suitable CMY planting regions.


2020 ◽  
Vol 12 (10) ◽  
pp. 4116
Author(s):  
Kemen Austin ◽  
Robert Beach ◽  
Daniel Lapidus ◽  
Marwa Salem ◽  
Naomi Taylor ◽  
...  

This study quantifies the potential responses of 11 staple crop yields to projected changes in temperature and precipitation in Rwanda, using a cross sectional model based on yield data collected across more than 14,000 villages. We incorporated a relatively high spatial resolution dataset on crop productivity, considered a broad range of crops relevant to national agricultural production priorities, used environmental data developed specifically for Rwanda, and reported uncertainty both from our estimation model and due to uncertainty in future climate projections. We estimate that future climate change will have the largest impacts on potential productivity of maize, bush bean, and Irish potato. All three crops are likely to experience a reduction in potential yields of at least 10% under Representative Concentration Pathway (RCP) 4.5 and at least 15% under RCP 8.5 by 2050. Notably, these are important crops nationally, and three of the crops targeted by Rwanda’s Crop Intensification Program. We find that the most severe reductions in potential crop yields will occur in the drier eastern savannah and plateau regions, but that the impacts of climate change could be neutral or even positive in the highlands through mid-century. The refined spatial scale of our analysis allows us to identify potentially vulnerable regions where adaptation investments may need to be prioritized to support food security and climate resilience in Rwanda’s agricultural sector.


2016 ◽  
Vol 20 (4) ◽  
pp. 1331-1353 ◽  
Author(s):  
Amir K. Basheer ◽  
Haishen Lu ◽  
Abubaker Omer ◽  
Abubaker B. Ali ◽  
Abdeldime M. S. Abdelgader

Abstract. The fate of seasonal river ecosystem habitats under climate change essentially depends on the changes in annual recharge of the river, which are related to alterations in precipitation and evaporation over the river basin. Therefore, the change in climate conditions is expected to significantly affect hydrological and ecological components, particularly in fragmented ecosystems. This study aims to assess the impacts of climate change on the streamflow in the Dinder River basin (DRB) and to infer its relative possible effects on the Dinder National Park (DNP) ecosystem habitats in Sudan. Four global circulation models (GCMs) from Coupled Model Intercomparison Project Phase 5 and two statistical downscaling approaches combined with a hydrological model (SWAT – the Soil and Water Assessment Tool) were used to project the climate change conditions over the study periods 2020s, 2050s, and 2080s. The results indicated that the climate over the DRB will become warmer and wetter under most scenarios. The projected precipitation variability mainly depends on the selected GCM and downscaling approach. Moreover, the projected streamflow is quite sensitive to rainfall and temperature variation, and will likely increase in this century. In contrast to drought periods during the 1960s, 1970s, and 1980s, the predicted climate change is likely to affect ecosystems in DNP positively and promote the ecological restoration for the habitats of flora and fauna.


Agriculture ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 593
Author(s):  
Oludare Sunday Durodola ◽  
Khaldoon A. Mourad

African countries such as Nigeria are anticipated to be more susceptible to the impacts of climate change due to reliance on rainfed agriculture. In this regard, the impacts of climate change on crop water requirements (CWR), yields and crop water productivity (CWP) of soybean in the Ogun-Ona River Basin, Nigeria, were evaluated for the baseline period (1986–2015) and future period (2021–2099) under Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios using AquaCrop Version 6.1. Future climate projections from the Swedish Meteorological and Hydrological Institute’s climate models (HadGEM2-ES and RCA4) were used in simulating the future scenarios. The results show that for the baseline period, CWR and yield are increasing while CWP shows a slight increase. For the future period, the CWR is projected to fluctuate and depend on the rainfall pattern. Meanwhile, carbon dioxide fertilization has positive effects on yield and is projected to increase up to 40% under RCP 8.5. The results of this study certainly offer useful information on suitable adaption measures which could be implemented by stakeholders and policymakers to improve soybean productivity in Nigeria.


Sign in / Sign up

Export Citation Format

Share Document