Rising tempetarures worldwide and especially the heat island effect in cities, heat waves and changes in rainfall pattern are among the many negative effects of climate change. Green spaces in cities help to cool the air – it has been calculated that one healthy tree has the same cooling effect as ten air-conditioning units. Heavy rainfall and flooding constitute another threat to our homes and settlements, urban transportation systems and health. Green infrastructure in cities increases the proportion of pervious surfaces and thus helps rainfall be absorbed into the ground reducing the risk of flooding. While in natural ecosystems around 50% of rainfall infiltrates into the soil (25% shallow infiltration and 25% deep infiltration), 10% runs off and 40% evapotranspirates, in heavilty transformed urban areas these ratios have been very much distorted. It has been calculated that in cities, only 15% of rainfall is able to infiltrate into the ground (10% shallow infiltration and 5% deep infiltration), 30% evapotranspirates and as much as 55% runs off on the surface causing flooding, creating a burden on the sewage system and depriving the soil under the paved surfaces of water necessary to support soil biota. Green Infrastructure is thus a modern tool of alleviating climate induced problems.

Cases

Väjxö, Sweden: storm water management

The city of Väjxö managed to deal with two problems at once by improving storm water management: reducing flooding on a low-lying street, and improving water quality in Väjxö lake. The city reopened the Linnaeus Canal on the low-lying street (Linnégatan), which had been flooding often. This particular action incorporates four adaptation measures: enhancing capacity of waters, adapting the design factor for flood protection, improved drainage in urban areas, and floating or elevated roads. The project was funded by the Swedish Local Investment Program for Sustainable Development (15%) and the Technical Department of the City of Väjxö (85%). It was implemented across a 3 year time span, from 1998-2001.

The canal is expected to last about 100 years, with maintenance required (sediment dredging). Since its reopening, the city has experienced only one severe flood. The Linnaeus Canal has helped the city to deal with the increase in rainfall that has occurred over the last fifteen years and may continue to increase due to climate change, as projected in the city’s climate adaptation strategy. The canal has also increased traffic safety by reducing the number of lanes in the street, which is located next to a secondary school. Moreover, as less storm water flows into the lake (instead ending up in the canal and sedimentation lagoons), the lake has fewer pollutants and can continue to play its role as a “beautiful element within the city”.

Source and further information: http://climate-adapt.eea.europa.eu/viewmeasure?ace_measure_id=4301

Stuttgart, Germany: green ventilation corridors

Stuttgart has aimed to deal with the common city problems of heat island effect and low air quality by creating green ventilation corridors. These corridors should allow air to flow to the city from the surrounding hills, as Stuttgart itself is located in a valley. Two measures were used to achieve this goal: public blue-green areas, and green roofs and walls. These strategies fit in with Stuttgart’s urban development slogan of “urban – compact – green”. The project was funded by the City of Stuttgart and the Verband Region Stuttgart, and emerged as an implementation of recommendations made in the Climate Atlas for the region of Stuttgart. The project itself was implemented by the Office for Urban Planning and Urban Renewal, with support from the Office for Urban Protection.

Thanks to the project, “over 39% of Stuttgart’s surface area has been put under the protection of nature conservation orders … greenery covers more than 60% of the city. Stuttgart contains 5,000 hectares of forests and woodland, 65,000 trees in parks and open spaces and 35,000 street trees. 300,000 square meters of rooftops have been greened and 40 out of 250 kilometres of tram tracks have been grassed (as of 2007). In line with the city development vision, 60 hectares of greenfield land previously earmarked for development has been cut from the 2010 land development plan to protect existing green space”

Source and further information: http://climate-adapt.eea.europa.eu/viewmeasure?ace_measure_id=3403

CarpathCC – Climate Change in the Carpathian region

The Carpathians are the largest European mountain range and pass through Austria, the Czech Republic, Slovakia, Poland, Hungary, Ukraine, Romania and Serbia. The catchment areas investigated in the present study may include adjacent areas that do not directly belong to what is defined as the Carpathian region. The CarpathCC Climate Change Framework Project aims to provide an in-depth assessment of the vulnerability of the Carpathian region to climate change and establish a diversified portfolio of sustainable adaptation measures with the active and valuable cooperation of international environmental experts. This policy decision support study will be produced in close cooperation with the most important stakeholder groups from the 7 countries of the Carpath Convention. Vulnerability of water, soil, forests, ecosystems and related production systems will be assessed in order to propose concrete ecosystem-based adaptation measures, including their costs and benefits. More information

Floating houses to fight climate change in the Netherlands

Dutch urban floating houses (Source: http://www.fredhoogervorst.com/photo/43100di/)

Description: The Netherlands implementing climate adaptation measures and building floating houses that are resistant to rising sea level and increase rainfall. 43 such homes were developed in the Steigereiland district in east Amsterdam. The Living with Water civil planning strategy involves re-flooding of formerly diked marshes, bringing defunct canals back into use, building catchment lakes, deepening rivers, moving dikes away river edges and redirecting rivers where necessary. 39 projects in river areas are currently being executed within the country’s flood protection program.

Cost of the program: 2.3 billion euros (39 projects)

Resources: http://www.inspirationgreen.com/floating-homes.html http://www.dw.de/floating-houses-to-fight-climate-change-in-holland/a-17532376

Resources