scholarly journals Exploring the added value of a long-term multidisciplinary dataset in drought research – a drought catalogue for southwestern Germany dating back to 1801

2020 ◽  
Author(s):  
Mathilde Erfurt ◽  
Georgios Skiadaresis ◽  
Erik Tijdeman ◽  
Veit Blauhut ◽  
Jürgen Bauhus ◽  
...  
Keyword(s):  
River Flow ◽  
Historical Context ◽  
Added Value ◽  
Drought Indices ◽  
Data Set ◽  
Tree Ring Data ◽  
Multiple Variables ◽  
Societal Impacts ◽  
Hydrological Droughts

Abstract. Droughts are multidimensional hazards that can lead to substantial environmental and societal impacts. To understand causes and impacts, multiple variables need to be considered. Many studies identified past drought events and investigated drought propagation from meteorological droughts via soil moisture to hydrological droughts and some studies have included the impacts of these different types of drought. Here, we analyse different droughts and their impacts in a regional context using a multidisciplinary approach and compiled a comprehensive and long-term data set to place recent drought events into a historical context. We assembled a dataset of drought indices and recorded impacts over the last 218 years in southwestern Germany. Meteorological and river-flow indices were used to assess the natural drought dynamics. In addition, tree-ring data and recorded impacts were utilized to investigate drought events from an ecological and social perspective. Since 1801, 20 extreme droughts were identified as common extreme events when applying the different indicators. All events were associated with societal impacts. Our multi-dataset approach provides insights into similarities but also the unique aspects of different drought indices and highlights the unprecedented frequency and severity of droughts in the 21st century.

scholarly journals A multidisciplinary drought catalogue for southwestern Germany dating back to 1801

2020 ◽  
Vol 20 (11) ◽  
pp. 2979-2995
Author(s):  
Mathilde Erfurt ◽  
Georgios Skiadaresis ◽  
Erik Tijdeman ◽  
Veit Blauhut ◽  
Jürgen Bauhus ◽  
...  
Keyword(s):  
River Flow ◽  
Historical Context ◽  
Drought Indices ◽  
Multiple Perspectives ◽  
Tree Ring Data ◽  
Different Types ◽  
Societal Impacts ◽  
Hydrological Droughts ◽  
Drought Occurrence

Abstract. Droughts are multidimensional hazards that can lead to substantial environmental and societal impacts. To understand causes and impacts, multiple perspectives need to be considered. Many studies have identified past drought events and investigated drought propagation from meteorological droughts via soil moisture to hydrological droughts, and some studies have included the impacts of these different types of drought. However, it is not certain whether the increased frequency and severity of drought events in the past decade is unprecedented in recent history. Therefore, we analyze different droughts and their impacts in a regional context using a multidisciplinary approach. We compile a comprehensive and long-term dataset to investigate possible temporal patterns in drought occurrence and place recent drought events into a historical context. We assembled a dataset of drought indices and recorded impacts over the last 218 years in southwestern Germany. Meteorological and river-flow indices were used to assess the natural drought dynamics. In addition, tree-ring data and recorded impacts were utilized to investigate drought events from an ecological and social perspective. Since 1801, 20 extreme droughts have been identified as common extreme events when applying the different indices. All events were associated with societal impacts. Our multi-dataset approach provides insights into similarities but also the unique aspects of different drought indices.

Exploring the added value of a long-term multidisciplinary dataset in drought research - a drought catalogue for southwestern Germany dating back to 1801

2020 ◽  
Author(s):  
Mathilde Erfurt ◽  
Georgios Skiadaresis ◽  
Erik Tijdeman ◽  
Veit Blauhut ◽  
Jürgen Bauhus ◽  
...  
Keyword(s):  
Extreme Events ◽  
Meteorological Data ◽  
Management Strategies ◽  
Added Value ◽  
Drought Indices ◽  
Drought Risk ◽  
Multiple Perspectives ◽  
Data Types ◽  
Tree Ring Data

<p>Droughts are multidimensional hazards that can lead to substantial negative environmental, societal and economic impacts. To understand drought processes, multiple perspectives need to be considered. Numerous studies have investigated drought propagation from meteorological droughts via soil moisture to hydrological droughts. Regional variation in drought regimes and anthropogenic influences make it difficult to find a direct connection between the multiple aspects of drought. Additionally, the lack of a comprehensive long-term multi data compilation limits our understanding of the severity and frequency of current drought events and therefore drought risk management strategies.</p><p>This study developed a multidisciplinary long-term dataset of drought indices and impact records in southwestern Germany for the time period between 1800 and 2018. It is based on meteorological data, streamflow records and tree-ring data as well as reported information on drought impacts. Drought events were classified into moderate, severe and extreme events based on each datatype separately, leading to a regional drought catalogue. Within this catalogue, 22 extreme drought events were identified as common events among different archives and data types. Ranking the ten most severe droughts per indicator uncovers extreme events in the 19th century. However the development of drought frequency and severity over the last two centuries highlights a unique intensification of drought events in the 21st century.</p><p>The multidisciplinary approach provides new insights into similarities but also unique aspects of different drought indicators. The catalogue identifies and includes numerous drought events of the past, which can be used for further risk related analysis as well as for planning and management of future events.</p>

scholarly journals A Long–Term Response-Based Rainfall-Runoff Hydrologic Model: Case Study of The Upper Blue Nile

Hydrology ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 69 ◽  
Author(s):  
Eatemad Keshta ◽  
Mohamed A. Gad ◽  
Doaa Amin
Keyword(s):  
River Flow ◽  
Hydrologic Model ◽  
Initial Assessment ◽  
Rainfall Runoff ◽  
Time Step ◽  
Data Set ◽  
Blue Nile ◽  
Catchment Areas ◽  
Surface And Groundwater

This study develops a response-based hydrologic model for long-term (continuous) rainfall-runoff simulations over the catchment areas of big rivers. The model overcomes the typical difficulties in estimating infiltration and evapotranspiration parameters using a modified version of the Soil Conservation Service curve number SCS-CN method. In addition, the model simulates the surface and groundwater hydrograph components using the response unit-hydrograph approach instead of using a linear reservoir routing approach for routing surface and groundwater to the basin outlet. The unit-responses are Geographic Information Systems (GIS)-pre-calculated on a semi-distributed short-term basis and applied in the simulation in every time step. The unit responses are based on the time-area technique that can better simulate the real routing behavior of the basin. The model is less sensitive to groundwater infiltration parameters since groundwater is actually controlled by the surface component and not the opposite. For that reason, the model is called the SCHydro model (Surface Controlled Hydrologic model). The model is tested on the upper Blue Nile catchment area using 28 years daily river flow data set for calibration and validation. The results show that SCHydro model can simulate the long-term transforming behavior of the upper Blue Nile basin. Our initial assessment of the model indicates that the model is a promising tool for long-term river flow simulations, especially for long-term forecasting purposes due to its stability in performing the water balance.

scholarly journals Consumers are willing to pay a price for explainable, but not for green AI. Evidence from a choice-based conjoint analysis

2022 ◽  
Vol 9 (1) ◽  
pp. 205395172110696
Author(s):  
Pascal D König ◽  
Stefan Wurster ◽  
Markus B Siewert
Keyword(s):  
Artificial Intelligence ◽  
Data Processing ◽  
Conjoint Analysis ◽  
Environmental Sustainability ◽  
Added Value ◽  
Energy Footprint ◽  
Explainable Ai ◽  
Societal Impacts ◽  
Shed Light

A major challenge with the increasing use of Artificial Intelligence (AI) applications is to manage the long-term societal impacts of this technology. Two central concerns that have emerged in this respect are that the optimized goals behind the data processing of AI applications usually remain opaque and the energy footprint of their data processing is growing quickly. This study thus explores how much people value the transparency and environmental sustainability of AI using the example of personal AI assistants. The results from a choice-based conjoint analysis with a sample of more than 1.000 respondents from Germany indicate that people hardly care about the energy efficiency of AI; and while they do value transparency through explainable AI, this added value of an application is offset by minor costs. The findings shed light on what kinds of AI people are likely to demand and have important implications for policy and regulation.

scholarly journals Evaluation of the relationship between meteorological and hydrological droughts in the southern Iberian Peninsula

2021 ◽  
Author(s):  
Emilio Romero-Jiménez ◽  
Matilde García-Valdecasas Ojeda ◽  
Patricio Yeste ◽  
Juan José Rosa-Cánovas ◽  
Sonia Raquel Gámiz-Fortis ◽  
...  
Keyword(s):  
Climate Change ◽  
Iberian Peninsula ◽  
River Flow ◽  
Standardized Precipitation Index ◽  
Meteorological Drought ◽  
Major Effect ◽  
Hydrological Drought ◽  
Drought Indices ◽  
Hydrological Response ◽  
Hydrological Droughts

<p>Society is facing a challenge due to climate change. Particularly, there are several areas where droughts will impact economic activities and landscapes, and decisions must be made in order to alleviate these effects. River flow regulation plays a major role in this regard, since it reduces the existing correlation between meteorological and hydrological droughts.<br>The aim of this work is to investigate the response of hydrological drought to meteorological drought under the influence of reservoir. To this effect, the Guadalquivir River Basin, in the southern Iberian Peninsula, has been studied. The aridity of this basin is expected to increase in the future, with longer and more severe meteorological droughts. Moreover, the Guadalquivir presents a strong regulation along its course. Therefore, streamflow and precipitation data have been analysed. With these data, meteorological and hydrological drought indices, such as the Standardized Precipitation Index (SPI), the Standardized Precipitation-Evapotranspiration Index (SPEI), and the Standardized Streamflow Index (SSI), have been calculated, focusing on how they correlate based on time scale and spatial distribution. The meteorological drought indices have been calculated in varying time scales, showing that the hydrological response is different depending on characteristics such as orography and river section. The correlation between the indices is generally strong in the study area, but the results show that its importance decreases as the streamflow becomes more regulated.<br>The results of this study could be added to the current tools for decision making in the economic fields that are most affected by droughts. Since droughts are a major effect of climate change in the area, this study could also act as a first step for the study of future droughts through climate and hydrological models.<br>Keywords: Drought indices, river regulation, hydrological response.<br>ACKNOWLEDGEMENTS: This work was funded by the FEDER / Junta de Andalucía - Ministry of Economy and Knowledge / Project [B-RNM-336-UGR18], and by the Spanish Ministry of Economy, Industry and Competitiveness, with additional support from the European Community Funds (FEDER) [CGL2017-89836-R].</p>

scholarly journals Evaluating the influence of long term historical climate change on catchment hydrology – using drought and flood indices

2013 ◽  
Vol 10 (2) ◽  
pp. 2373-2428 ◽  
Author(s):  
I. B. Karlsson ◽  
T. O. Sonnenborg ◽  
K. H. Jensen ◽  
J. C. Refsgaard
Keyword(s):  
Climate Change ◽  
Hydrological Model ◽  
Climate Change Impacts ◽  
Kendall Test ◽  
Drought Indices ◽  
Threshold Method ◽  
Data Set ◽  
Stream Discharge ◽  
Predict Climate Change

Abstract. This study uses a 133 yr data set from the 1055 km2 Skjern River catchment in a western Danish catchment to evaluate: long-term past climate changes in the area; the capability of a conceptual hydrological model NAM to simulate climate change impacts on river discharge; and the occurrences of droughts and floods in a changing climate. The degree of change in the climatic variables is examined using the non-parametric Mann-Kendall test. During the last 133 yr the area has experienced a significant change in precipitation of 46% and a temperature change of 1.3 °C leading to (simulated) increases in discharge of 103% and groundwater recharge of 172%. Only a small part of the past climatic changes was found to be correlated to the climatic drivers: NAO, SCA and AMO. The NAM model was calibrated on the period 1961–1970 and showed generally an excellent match between simulated and observed discharge. The capability of the hydrological model to predict climate change impact was investigated by looking at performances outside the calibration period. The results showed a reduced model fit, especially for the modern time periods (after the 1970s), and not all hydrological changes could be explained. This might indicate that hydrological models cannot be expected to predict climate change impacts on discharge as accurately in the future, as they perform under present conditions, where they can be calibrated. The (simulated) stream discharge was subsequently analyzed using flood and drought indices based on the threshold method. The extreme signal was found to depend highly on the period chosen as reference to normal. The analysis, however, indicated enhanced amplitude of the hydrograph towards the drier extremes superimposed on the overall discharge increase leading to more relative drought periods.

scholarly journals The regional MiKlip decadal forecast ensemble for Europe: the added value of downscaling

2014 ◽  
Vol 7 (6) ◽  
pp. 2983-2999 ◽  
Author(s):  
S. Mieruch ◽  
H. Feldmann ◽  
G. Schädler ◽  
C.-J. Lenz ◽  
S. Kothe ◽  
...  
Keyword(s):  
Decadal Variability ◽  
Climate Prediction ◽  
Skill Assessment ◽  
Added Value ◽  
Lead Times ◽  
Data Set ◽  
Regional Downscaling ◽  
Decadal Climate ◽  
Decadal Climate Prediction

Abstract. The prediction of climate on time scales of years to decades is attracting the interest of both climate researchers and stakeholders. The German Ministry for Education and Research (BMBF) has launched a major research programme on decadal climate prediction called MiKlip (Mittelfristige Klimaprognosen, Decadal Climate Prediction) in order to investigate the prediction potential of global and regional climate models (RCMs). In this paper we describe a regional predictive hindcast ensemble, its validation, and the added value of regional downscaling. Global predictions are obtained from an ensemble of simulations by the MPI-ESM-LR model (baseline 0 runs), which were downscaled for Europe using the COSMO-CLM regional model. Decadal hindcasts were produced for the 5 decades starting in 1961 until 2001. Observations were taken from the E-OBS data set. To identify decadal variability and predictability, we removed the long-term mean, as well as the long-term linear trend from the data. We split the resulting anomaly time series into two parts, the first including lead times of 1–5 years, reflecting the skill which originates mainly from the initialisation, and the second including lead times from 6–10 years, which are more related to the representation of low frequency climate variability and the effects of external forcing. We investigated temperature averages and precipitation sums for the summer and winter half-year. Skill assessment was based on correlation coefficient and reliability. We found that regional downscaling preserves, but mostly does not improve the skill and the reliability of the global predictions for summer half-year temperature anomalies. In contrast, regionalisation improves global decadal predictions of half-year precipitation sums in most parts of Europe. The added value results from an increased predictive skill on grid-point basis together with an improvement of the ensemble spread, i.e. the reliability.

Liberating Afghan Women

2004 ◽  
Vol 21 (3) ◽  
pp. 70-88 ◽  
Author(s):  
Nancy Gallagher
Keyword(s):  
United States ◽  
Human Rights ◽  
Historical Context ◽  
The United States ◽  
Political Organizations ◽  
Way Of Life ◽  
Afghan Women ◽  
The Media ◽  
Policy Priority

Public opinion in the United States and elsewhere celebrated the liberation of Afghan women following the defeat of the Taliban government. The United States promised to stay in Afghanistan and foster security, economic development, and human rights for all, especially women. After years of funding various anti- Soviet Mujahidin warlords, the United States had agreed to help reconstruct the country once before in 1992, when the Soviet-backed government fell, but had lost interest when the warlords began to fight among themselves. This time, however, it was going to be different. To date, however, conditions have not improved for most Afghan women and reconstruction has barely begun. How did this happen? This article explores media presentations of Afghan women and then compares them with recent reports from human rights organizations and other eyewitness accounts. It argues that the media depictions were built on earlier conceptions of Muslim societies and allowed us to adopt a romantic view that disguised or covered up the more complex historical context of Afghan history and American involvement in it. We allowed ourselves to believe that Afghans were exotic characters who were modernizing or progressing toward a western way of life, despite the temporary setback imposed by the Taliban government. In Afghanistan, however, there was a new trope: the feminist Afghan woman activist. Images of prominent Afghan women sans burqa were much favored by the mass media and American policymakers. The result, however, was not a new focus on funding feminist political organizations or making women’s rights a foreign policy priority; rather, it was an unwillingness to fulfill obligations incurred during decades of American-funded mujahidin warfare, to face the existence of deteriorating conditions for women, resumed opium cultivation, and a resurgent Taliban, or to commit to a multilateral approach that would bring in the funds and expertise needed to sustain a long-term process of reconstruction.

scholarly journals Documentary data and the study of past droughts: a global state of the art

2018 ◽  
Vol 14 (12) ◽  
pp. 1915-1960 ◽  
Author(s):  
Rudolf Brázdil ◽  
Andrea Kiss ◽  
Jürg Luterbacher ◽  
David J. Nash ◽  
Ladislava Řezníčková
Keyword(s):  
Large Scale ◽  
State Of The Art ◽  
Drought Indices ◽  
Documentary Evidence ◽  
Climatic Trends ◽  
Instrumental Observations ◽  
Spatio Temporal ◽  
Epigraphic Evidence ◽  
Administrative Evidence

Abstract. The use of documentary evidence to investigate past climatic trends and events has become a recognised approach in recent decades. This contribution presents the state of the art in its application to droughts. The range of documentary evidence is very wide, including general annals, chronicles, memoirs and diaries kept by missionaries, travellers and those specifically interested in the weather; records kept by administrators tasked with keeping accounts and other financial and economic records; legal-administrative evidence; religious sources; letters; songs; newspapers and journals; pictographic evidence; chronograms; epigraphic evidence; early instrumental observations; society commentaries; and compilations and books. These are available from many parts of the world. This variety of documentary information is evaluated with respect to the reconstruction of hydroclimatic conditions (precipitation, drought frequency and drought indices). Documentary-based drought reconstructions are then addressed in terms of long-term spatio-temporal fluctuations, major drought events, relationships with external forcing and large-scale climate drivers, socio-economic impacts and human responses. Documentary-based drought series are also considered from the viewpoint of spatio-temporal variability for certain continents, and their employment together with hydroclimate reconstructions from other proxies (in particular tree rings) is discussed. Finally, conclusions are drawn, and challenges for the future use of documentary evidence in the study of droughts are presented.

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