Evaluation of the European Seasonal forecast Models for hydrological forecasting for improved water management in Africa

Author(s):  
Solomon Hailu Gebrechorkos ◽  
Justin Sheffield

<p>Extreme drought and floods have a large societal impact if not appropriately monitored and if mitigation/adaptation measures are not developed and modified based on early warning of these events. Currently, there are only a few global seasonal forecast models available with a high temporal (e.g., daily) but coarse spatial resolution (~1°) that can provide early warning operationally. Application of these forecast models for long-term (up to 6-7 months) hydrological forecasting first requires evaluation of their skill against observed data. In this study, five European seasonal forecast models; Copernicus Climate Change Service (ECMWF), UK Met Office, Météo France, Deutscher Wetterdienst (DWD), and Centro Euro-Mediterraneo sui Cambiamenti Climatici (CMCC), are used. The Multi-Source Weighted-Ensemble Precipitation (MSWEP) and Princeton Global Forcing (PGF) available at high spatial and temporal resolution are used as a reference dataset for precipitation and maximum and minimum temperature, respectively. Multiple methods such as correlation, percentage of bias and root mean square error and rainfall onset and cessation are used to evaluate the skill of individual models on daily, monthly, seasonal, and climatological periods. In addition, extreme indices (e.g., consecutive dry and wet days) developed by the Expert Team on Climate Change Detection and Indices (ETCCDI) are used. Finally, a bias-corrected multi-model weighted ensemble forecast is developed as input into a global hydrological model (Variable Infiltration Capacity (VIC)) for seasonal hydrological forecasting in Africa.</p>

2015 ◽  
Vol 3 (7) ◽  
pp. 4353-4389
Author(s):  
S. Quiroga ◽  
C. Suárez

Abstract. This paper examines the effects of climate change and drought on agricultural outputs in Spanish rural areas. By now the effects of drought as a response to climate change or policy restrictions have been analyzed through response functions considering direct effects on crop productivity and incomes. These changes also affect incomes distribution in the region and therefore modify the social structure. Here we consider this complementary indirect effect on social distribution of incomes which is essential in the long term. We estimate crop production functions for a range of Mediterranean crops in Spain and we use a decomposition of inequalities measure to estimate the impact of climate change and drought on yield disparities. This social aspect is important for climate change policies since it can be determinant for the public acceptance of certain adaptation measures in a context of drought. We provide the empirical estimations for the marginal effects of the two considered impacts: farms' income average and social income distribution. In our estimates we consider crop productivity response to both bio-physical and socio-economic aspects to analyze long term implications on both competitiveness and social disparities. We find disparities in the adaptation priorities depending on the crop and the region analyzed.


Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1498 ◽  
Author(s):  
Solomon Mulugeta ◽  
Clifford Fedler ◽  
Mekonen Ayana

With climate change prevailing around the world, understanding the changes in long-term annual and seasonal rainfall at local scales is very important in planning for required adaptation measures. This is especially true for areas such as the Awash River basin where there is very high dependence on rain- fed agriculture characterized by frequent droughts and subsequent famines. The aim of the study is to analyze long-term trends of annual and seasonal rainfall in the Awash River Basin, Ethiopia. Monthly rainfall data extracted from Climatic Research Unit (CRU 4.01) dataset for 54 grid points representing the entire basin were aggregated to find the respective areal annual and seasonal rainfall time series for the entire basin and its seven sub-basins. The Mann-Kendall (MK) test and Sen Slope estimator were applied to the time series for detecting the trends and for estimating the rate of change, respectively. The Statistical software package R version 3.5.2 was used for data extraction, data analyses, and plotting. Geographic information system (GIS) package was also used for grid making, site selection, and mapping. The results showed that no significant trend (at α = 0.05) was identified in annual rainfall in all sub-basins and over the entire basin in the period (1902 to 2016). However, the results for seasonal rainfall are mixed across the study areas. The summer rainfall (June through September) showed significant decreasing trend (at α ≤ 0.1) over five of the seven sub-basins at a rate varying from 4 to 7.4 mm per decade but it showed no trend over the two sub-basins. The autumn rainfall (October through January) showed no significant trends over four of the seven sub-basins but showed increasing trends over three sub-basins at a rate varying from 2 to 5 mm per decade. The winter rainfall (February through May) showed no significant trends over four sub-basins but showed significant increasing trends (at α ≤ 0.1) over three sub-basins at a rate varying from 0.6 to 2.7 mm per decade. At the basin level, the summer rainfall showed a significant decreasing trend (at α = 0.05) while the autumn and winter rainfall showed no significant trends. In addition, shift in some amount of summer rainfall to winter and autumn season was noticed. It is evident that climate change has shown pronounced effects on the trends and patterns of seasonal rainfall. Thus, the study contribute to better understanding of climate change in the basin and the information from the study can be used in planning for adaptation measures against a changing climate.


2021 ◽  
Vol 1 ◽  
pp. 9
Author(s):  
Fred Sanders ◽  
Hugo Sanders ◽  
Karen Jonkers

Gdansk in Poland and the Netherlands share a long-term relationship that started with the establishment of Dutch Mennonites in the Vistula delta in the 16th Century. Climate-change figures show that both the Polish Gdansk and DutchRotterdam deltas will suffer flooding due to sea level rise, with accumulating severe rainfall accompanied by high river levels; reasons that led to a comparison of the adaptation measures taken. On the basis of the crossover comparison studied, it can be concluded that Poland and the Netherlands have a virtually identical approach when it comes to climate-change impacts on their current situation. With regard to the long-term climate-change trend, the Netherlands in exploring for the future more ‘anticipatory’ measures with the development of new scenarios for the protection of land and cities. In the Netherlands the use of Hackathon approach is thereby used more often to explore such scenarios. The interaction between the experts and stakeholders of different expertise in this methodology show to lead to creative and new perspectives. This approach may also be recommended for the situation in Gdansk.


2018 ◽  
Vol 6 (6) ◽  
pp. 205-211
Author(s):  
Oyerinde G. T. ◽  
Olowookere B.T.

Sub-Saharan Africa have low resilience capacities to the challenges of climate change. This study is aimed at assessing climate trends and regime shifts at the Sota Catchment, Benin. Long term rainfall and river discharge were analyzed from 1950-2010 in order to generate patterns of changes in the basin. Analysis of the hydro-meteorological were based on the two prominent vegetation zones (Sudan and Guinea Savannah) in the catchment. The rainfall and discharge data were subjected to regime shift analysis and Standardized Precipitation Indices (SPI) were computed. Downward trend of precipitation was observed in the Guinea and Sudan vegetation zones of the catchments from 1970. Rainfall and runoff amount at the two assessed vegetation zones was different in the Guinea and Sudan zone up till 1970. Clear merge of rainfall and runoff amount and patterns was witnessed between the two vegetation zones at 2007. This calls for attention of scientists and policy makers in the region to deploy necessary adaptation measures based on such clear evidence of climate change.


Hydrology ◽  
2019 ◽  
Vol 6 (1) ◽  
pp. 22 ◽  
Author(s):  
Rawshan Ali ◽  
Arez Ismael ◽  
Arien Heryansyah ◽  
Nadeem Nawaz

The assessment of trends in river flows has become of interest to the scientific community in order to understand the changing characteristics of flow due to climate change. In this study, the trends in river flow of Dukan Dam located in the northern part of Iraq were assessed. The assessment was carried out for the period 1964 to 2013 using Sen’s slope and the Mann–Kendall test. Sen’s slope was used to assess the magnitude of change while the Mann–Kendall trend test was used to confirm the significance of trends. The results of the study showed that there was a decreasing trend in river flow both annually and for all individual months. The highest decreasing trend of −5.08846 m3/month was noticed in April, while the lowest change of −1.06022 m3/month was noticed in November. The annual flow also showed a significant decrease at a rate of −1.912 m3/year at a 95% level of confidence. Additionally, the findings of the study also confirmed that a decrease in precipitation and the construction of hydraulic structures reduced the flow in the river. The findings of the study suggest that decreasing trends may cause a water-scarce situation in the future if proper adaptation measures are not taken.


Author(s):  
Stefan Friedrich ◽  
Torben Hilmers ◽  
Claudia Chreptun ◽  
Elizabeth Gosling ◽  
Isabelle Jarisch ◽  
...  

AbstractForest management faces growing uncertainty concerning environmental conditions and demand for ecosystem services. To help forest managers consider uncertainty, we applied a robust and multi-criteria approach to select the optimal composition of a forest enterprise from 12 stand types. In our simulation, the forest enterprise strives for either financial return or a multi-criteria forest management considering financial return, carbon storage and forest ecosystem stability. To quantify the influence of climate change on these decision criteria, we used the concept of analogous climate zones. Our results provide recommendations for long-term strategies for tree species selection in a Southeast German forest enterprise. The results show that considering both uncertainty and multifunctionality in forest management led to more diversified forest compositions. However, robust and multi-criteria optimisation required the forest enterprise to pay a premium in terms of lower income. Financial returns decreased when forest composition accounted for uncertainty or multiple objectives. We also found that adaptation measures could only partly financially compensate the effects of climate change. As the study is limited to two tree species, including additional tree species, variants of mixing proportions and further silvicultural strategies in the optimisation appears a promising avenue for future research.


2009 ◽  
Vol 4 (1) ◽  
pp. 3-6
Author(s):  
Syunsuke Ikeda ◽  
◽  

As pointed out by Assessment Report 4 of IPCC, global climate change will increase the magnitude and frequency of water-related disasters such as flooding, surge and drought. In addition to this the social changes such as population problems in Japan will aggravate the vulnerability to the disasters. Two concepts to cope with the water-related disasters triggered by climate change are adaptation and mitigation. Though abatement of GHG gas emissions has been eagerly argued, Japan should be more concerned with and take the initiative both for mitigation and adaptation. As adaptation measures for water-related disasters, 3 measures are proposed in this paper; building disaster-awareness societies, building physical/social structures, and adaptation R&D. In addition to them, it is necessary to bring reconstruction of the national land into medium- and long term views as paradigm shift. In this paper, the following recommendations are proposed for the adaptation: the Japanese government should be aware of the importance of adaptation and strongly promote adaptation to mitigate water-related disasters, and the government should also cooperate in establishing adaptation in sustaining development of Asian monsoon areas and development programs.


2016 ◽  
Vol 113 (10) ◽  
pp. 2597-2602 ◽  
Author(s):  
Matthias Mengel ◽  
Anders Levermann ◽  
Katja Frieler ◽  
Alexander Robinson ◽  
Ben Marzeion ◽  
...  

Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28–56 cm, 37–77 cm, and 57–131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The “constrained extrapolation” approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections.


2016 ◽  
Vol 16 (6) ◽  
pp. 1369-1385 ◽  
Author(s):  
Sonia Quiroga ◽  
Cristina Suárez

Abstract. This paper examines the effects of climate change and drought on agricultural incomes in Spanish rural areas. Present research has focused on the effects of these extreme climatological events through response functions, considering effects on crop productivity and average incomes. Among the impacts of droughts, we focused on potential effects on income distribution. The study of the effects on abnormally dry periods is therefore needed in order to perform an analysis of diverse social aspects in the long term. We estimate crop production functions for a range of Mediterranean crops in Spain and we use a measure of the decomposition of inequality to estimate the impact of climate change and drought on yield disparities. Certain adaptation measures may require a better understanding of risks by the public to achieve general acceptance. We provide empirical estimations for the marginal effects of the two impacts considered: farms' average income and income distribution. Our estimates consider crop production response to both biophysical and socio-economic aspects to analyse long-term implications on competitiveness and disparities. As for the results, we find disparities in the adaptation priorities depending on the crop and the region analysed.


2015 ◽  
Vol 10 (3) ◽  
pp. 420-428 ◽  
Author(s):  
Nobuo Shirai ◽  
◽  
Mitsuru Tanaka

Additional adaptation measures such as “basic improvement of sensitivity” and “adaptive governance against mid and long term impacts” are set as ideal directions for local governments. The study of the situations for implementing additional adaptation measures by local governments were determined by using checklists. It is clarified as a result that additional adaptation measures have not been considered enough. The following problems in implementing measures from the “Japan local Forum for Climate Change Adaptation Society” were found: (1) Prediction and evaluation of climate change impacts, (2) Concretization and evaluation of adaptation measures, (3) Communication and subject formation and (4) Implementation of the measures and preparation of conditions. In the future, it is necessary to concretize additional adaptation measures at the research level, to share these additional adaptation measures with concerned parties and to promote the exchange of opinions.


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