Abstract
Water management and environmental protection is vulnerable to extreme low flows during streamflow droughts. During the last decades, in most rivers of Central Europe summer runoff and low flows have decreased. Discharge projections agree that future decrease in runoff is likely for catchments in Brandenburg, Germany. Depending on the first-order controls on low flows, different adaption measures are expected to be appropriate. Small catchments were analyzed because they are expected to be more vulnerable to a changing climate than larger rivers. They are mainly headwater catchments with smaller ground water storage. Local characteristics are more important at this scale and can increase vulnerability.
This thesis mutually evaluates potential adaption measures to sustain minimum runoff in small catchments of Brandenburg, Germany, and similarities of these catchments regarding low flows. The following guiding questions are addressed: (i) Which first-order controls on low flows and related time scales exist? (ii) Which are the differences between small catchments regarding low flow vulnerability? (iii) Which adaption measures to sustain minimum runoff in small catchments of Brandenburg are appropriate considering regional low flow patterns?
Potential adaption measures to sustain minimum runoff during periods of low flows can be classified into three categories: (i) increase of groundwater recharge and subsequent baseflow by land use change, land management and artificial ground water recharge, (ii) increase of water storage with regulated outflow by reservoirs, lakes and wetland water management and (iii) regional low flow patterns have to be considered during planning of measures with multiple purposes (urban water management, waste water recycling and inter-basin water transfer). The question remained whether water management of areas with shallow groundwater tables can efficiently sustain minimum runoff. Exemplary, water management scenarios of a ditch irrigated area were evaluated using the model Hydrus-2D. Increasing antecedent water levels and stopping ditch irrigation during periods of low flows increased fluxes from the pasture to the stream, but storage was depleted faster during the summer months due to higher evapotranspiration. Fluxes from this approx. 1 km long pasture with an area of approx. 13 ha ranged from 0.3 to 0.7 ls-1 depending on scenario. This demonstrates that numerous of such small decentralized measures are necessary to sustain minimum runoff in meso-scale catchments.
Differences in the low flow risk of catchments and meteorological low flow predictors were analyzed. A principal component analysis was applied on daily discharge of 37 catchments between 1991 and 2006. Flows decreased more in Southeast Brandenburg according to meteorological forcing. Low flow risk was highest in a region east of Berlin because of intersection of a more continental climate and the specific geohydrology. In these catchments, flows decreased faster during summer and the low flow period was prolonged. A non-linear support vector machine regression was applied to iteratively select meteorological predictors for annual 30-day minimum runoff in 16 catchments between 1965 and 2006. The potential evapotranspiration sum of the previous 48 months was the most important predictor (r2 = 0.28). The potential evapotranspiration of the previous 3 months and the precipitation of the previous 3 months and last year increased model performance (r2 = 0.49, including all four predictors). Model performance was higher for catchments with low yield and more damped runoff. In catchments with high low flow risk, explanatory power of long term potential evapotranspiration was high.
Catchments with a high low flow risk as well as catchments with a considerable decrease in flows in southeast Brandenburg have the highest demand for adaption. Measures increasing groundwater recharge are to be preferred. Catchments with high low flow risk showed relatively deep and decreasing groundwater heads allowing increased groundwater recharge at recharge areas with higher altitude away from the streams. Low flows are expected to stay low or decrease even further because long term potential evapotranspiration was the most important low flow predictor and is projected to increase during climate change. Differences in low flow risk and runoff dynamics between catchments have to be considered for management and planning of measures which do not only have the task to sustain minimum runoff.
Literaturrecherche und Analyse der Bewirtschaftungspläne von 18 deutschen und europäischen Flussgebietseinheiten. Der Bericht untersucht inwieweit die zu erwartenden Auswirkungen des Klimawandels in die ökonomischen Analysen gemäß Wasserrahmenrichtlinie integriert wurden.
Dieses artec-Paper fasst Ergebnisse einer explorativen qualitativen Studie zusammen, in der unterschiedliche gesellschaftliche Gruppen zu ihrer Wahrnehmung des Klimawandels befragt wurden. Ausgangspunkte der Studie waren die Intensivierung der Klimawandeldebatte Mitte der 2000er Jahre sowie Erkenntnisse über eine damit verbundene Sensibilisierung der Bevölkerung. Vor diesem Hintergrund ging die Untersuchung der Frage nach, inwieweit sich eine solche Sensibilisierung bei den Bürgerinnen und Bürgern widerspiegelt und Veränderungen in deren Konsumverhalten bewirkt.
As a gateway between ground and sea transportation, and as
a business location for service and industry, ports are of great significance for the regional and national economy. At the same time, port structures are located in regions threatened by storms and rising sea levels. Due to highly interdependent value chains,weather related disruptions in port operation can cause serious economic damage. Thus, adaptation to possible climate impacts seems like an obvious task for port authorities. The article analyses the climate vulnerability of German Baltic port locations.
Der Bericht beschreibt die Aktivitäten des Projekts RADOST in den fünf Modulen „Netzwerk und Dialog“, „Natur- und ingenieurwissenschaftliche Forschung“, „Sozio-ökonomische Analyse“, „Nationaler und europäischer Politikrahmen/ nationaler und internationaler Austausch“ und „Kommunikation und Verbreitung der Ergebnisse“ und deckt den Zeitraum von April 2012 bis Januar 2013 ab.
Das Projekt „Regionale Anpassungsstrategien für die deutsche Ostseeküste“ (RADOST) wird im Rahmen der Maßnahme „Klimawandel in Regionen zukunftsfähig gestalten“ (KLIMZUG) vom Bundesministerium für Bildung und Forschung gefördert. Nach knapp zwei Dritteln der Projektlaufzeit bot die RADOST-Tour 2012 ausführlich Gelegenheit, die inzwischen vorhandenen Projektergebnisse zu diskutieren. In den thematisch gegliederten Veranstaltungsprotokollen werden die Inhalte der Veranstaltungen und die wichtigsten Punkte der Diskussionen präsentiert.
Adaptation to climate change requires the implementation of new and revision of existing policies in order to change collective behaviour in a way that reduces vulnerability to the impacts of climate change. At the same time, the efficiency of environmental governance has been questioned due to perceived deficiencies in implementation in the past. As a consequence, it is observed that high levels of adaptive capacity are often not used for adaptive action, and therefore communities remain vulnerable. This thesis is looking at the socio-cognitive dimension of adaptation from the perspective of socio-cultural construction of values and practices that influence risk perceptions and behavioural intentions in coastal management and adaptation to climate variability and change. The construction of values and practices is analysed through discursive fields on the respective topics in local media from three states on the US mid-Atlantic coast.