Implementation of a forecAsting System for urban heaT Island effect for the development of urban adaptation strategies

PROJECT DESCRIPTION

BACKGROUND

The combined effects of global climate change and rapid urbanisation is expected to make residents of urban areas more vulnerable to a broad range of environmental problems. These are strongly connected with the urban heat island (UHI) effect, which will become more disruptive as heat waves become more frequent and last longer due to climate change and urban overpopulation. Thessaloniki’s urban area covers 112 km² and has a population of around 790 000 inhabitants, while the urban area of Rome (around 1 287 km²) extends beyond the administrative city limits and is home to more than 2.8 million residents. Older people (aged 65 and above), who are more sensitive to heat exhaustion, account for 12% of the population of Thessaloniki and 20% of the population of Rome, one of the first cities to have introduced a heat health warning (HWW) system. Based on this HWW system, the Lazio region developed a heat prevention plan that includes surveillance by GPs of vulnerable groups of people (e.g., the elderly and those with pre-existing chronic diseases).

OBJECTIVES

The project specific objectives encompassed:

1. designing, implementing, running pilots and validating a set of UHI forecasting systems in Thessaloniki and Rome, based on state-of-the-art numerical models: these modeling systems provided stakeholders with several UHI-related, high resolution forecasting products, including thermal bioclimate indices, as well as Heating and Cooling Degree Days to estimate energy demand of buildings. Furthermore, such forecasting models drove the operational test of the Heat Health Warning Systems in both cities, helping local authorities to react appropriately to extreme events;
2. the establishment of dissemination tools and creation of open accesses to UHI-related information and products for the end-users with Information and Communication Technology (ICT) applications: these tools helped concerned authorities and the general public to fill the knowledge gap on local climate vulnerabilities and risks;
3. an assessment of the impact of future climate change scenarios on UHI for the two selected cities;
4. an evaluation of the impacts of promoting green activities (e.g., green roofs, ventilation areas, etc.) in urban areas to combat the UHI effect using the modelling systems developed for the two selected cities;
5. the development of good practice guides and efficient strategic plans for mitigating future UHI effects in the involved cities, as well as in other EU urban areas which face the same UHI adverse impacts;
6. awareness raising and prompting authorities to apply urban adaptation strategies and mitigation initiatives developed by the project: this aimed to contribute and support the Signatories’ commitment to “Mayors Adapt” and “Covenant of Mayors”;
7. the organisation of events to promote, replicate and transfer the designed modeling systems and the best urban adaptation.

RESULTS

The project managed to design, demonstrate and validate a set of Urban Heat Island (UHI) forecasting systems in Rome (Italy) and Thessaloniki (Greece). The pilot operations of the forecasting systems in the two project cities led to their further optimisation. During the project duration, the systems were also replicated in Heraklion (Crete, Greece), and two more replication cities were added (Civitavechia - Italy, Pavlos Melas - Greece), where the forecasting system will be implemented for 5 years after the project's end. This work set solid foundations for the use of the systems also in Nicosia through a new LIFE project: LIFE21 GIE/GR/74365 - SIRIUS.

 

A simulation was carried out to assess the effect of the adaptation strategies of the two project cities (Thessaloniki and Rome) in the mitigation of the UHI effect. Based on the scientific work of AuTH, UHI intensity in urbanised areas of South Europe is estimated at 2-3˚C above air ambient temperature. Greening measures covering 30% of the area of Thessaloniki can reduce the effect by 0.5˚C, while if the measures are applied in 70% of the city, the UHI effect can be reduced up to 1˚C. This information was used in the application of the pilot actions in the two project municipalities. The above results and measures were integrated in the strategic adaptation plan of the municipality of Thessaloniki.