Changes in seasonality of groundwater level fluctuations in a temperate-cold climate transition zone

In\ua0cold (i.e. boreal, subarctic, snowy)\ua0climate\ua0zones, dynamic\ua0groundwater\ua0storage is greatly affected by the timing and amount of snowmelt. With global warming, cold climates\ua0in\ua0the northern hemisphere will\ua0transition\ua0to temperate. As temperatures rise, the dominant type of precipitation will\ua0change\ua0from snow to rain\ua0in\ua0winter. Further, the growing season is prolonged. This has\ua0a\ua0direct impact on the aquifer recharge pattern. However, little is known about the effect of changing annual recharge regimes on\ua0groundwater\ua0storage. The present work deduces the impact of shifting\ua0climate\ua0zones on\ua0groundwater\ua0storage by evaluating the effect of\ua0climate\ua0seasonality\ua0on intra-annual hydraulic head\ua0fluctuations. The work compares intra-annual hydraulic head\ua0fluctuations\ua0in\ua0a\ua0temperate-cold\ua0climate\ua0transition\ua0zone\ua0(Fennoscandia) from two different periods (1980–1989, 2001–2010). This is done by associating rising vs. declining hydraulic heads with hydrometeorology. Due to the northwards migration of the temperate\ua0climate\ua0zone, there is\ua0a\ua0shift\ua0in\ua0seasonality\ua0between the two periods. This has\ua0a\ua0negative impact on\ua0groundwater\ua0levels, which are significantly lower\ua0in\ua02001–2010, particularly near the\ua0climate\ua0transition\ua0zone. The results demonstrate that increasing temperatures\ua0in\ua0cold\ua0climate\ua0regions may\ua0change\ua0the\ua0seasonality\ua0of\ua0groundwater\ua0recharge, by altering the main recharge period from being snowmelt-dominated (spring) to rain-dominated (winter). Additionally, this is connected to the duration of the growing season, which impedes\ua0groundwater\ua0recharge. The coupled effect of this on\ua0groundwater\ua0in\ua0the study area has led to\ua0a\ua0significant decrease\ua0in\ua0groundwater\ua0storage

Hydrological Feasibility of Flood Barriers to Protect the Gothenburg (Sweden) during the 21st Century - An Initial Assessment

Climate change due to increasing of greenhouse gas emissions to the atmosphere will cause mean sea level to rise about +1 m by 2100. To prevent coastal floods resulted from the sea level rising, different flood control structures have been built and showed acceptable protection levels at least so far; e.g. Thames Barrier in London, UK. Gothenburg city on the south-west coast of Sweden, with the G\uf6ta \ue4lv River running through it, is one of vulnerable cities to the accelerated sea level rise. Besides, a high tide in southern Sweden will be increased to +2 m above the current sea level by 2100. Hence, most parts of Gothenburg will experience flooding events during the 21st century, even the City Planning Office of Gothenburg suggests +2.5 m above the current sea level as the safe level for setting the shelter of especially important facilities by 2100. Developing water level model by MATLAB, we investigated the hydrological feasibility of using flood barriers in the G\uf6ta \ue4lv River to protect the Gothenburg city against flooding events during this century. One flood control barrier at the river upstream (upstream barrier) in the Gothenburg region and a sea barrage (G\uf6ta \ue4lv barrage) at the entrance point of the river to the North Sea were suggested by this study. Considering three operational scenarios for these barriers, the highest sea level was estimated to +2.95 m above the current mean sea level by 2100. To prove flood protection against such high sea levels, both barriers have to be closed. In order to prevent high water levels in the G\uf6ta \ue4lv reservoir due to the runoff generation from rainfall, the barriers would be open when the sea level is low. This preliminary assessment concluded the suggested sea and flood barriers would successfully protect the Gothenburg city from flooding events during the 21st century

Does groundwater protection in Europe require new EU-wide environmental quality standards?

The European Groundwater Directive could be improved by limiting the scopes of the Annexes I and II to the manmade and natural substances, respectively, and by defining a common monitoring protocol. The changes in the European landuse patterns, in particular the urban sprawl phenomena, obscure the distinction between the point and diffuse sources of contamination. In the future more importance will be given to the household contamination. Moreover, the agricultural environment could be used for developing new conceptual models related to the pharmaceuticals