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Upgrading the environmental and energy performance of existing buildings has taken in recent years a central role in the issues related to sustainability and energy saving. More than 75% of the energy consumed for heating and air-conditioning is essentially wasted due to inefficient insulation wrap, poor sealing of windows and poor performances of the plants’ system. The identification of the most appropriate retrofitting options is a topic of outstanding importance given the potential costs and impacts involved. To ensure replicable results across the EU context, the research methodology presented in this paper is based on the assumption that the solution has to be found in a multi-disciplinary process applicable to almost all the possible scenarios. Standardized interventions are not the effective and sustainable solutions that we are looking for, pre-made receipts are generally addressed towards one main issue are partly effective and not efficient considering the life cycle of the building. The aim is to combine technologies and design tools in one integrated process: 1) Offering an interesting payback time. 2) Increasing the energy performances of the envelope through variable solutions which increase the participation of the users. 3) Overcoming the existing socio-economic barriers. © 2014 WIT Press.

Energy efficiency in housing is more than a technical problem, since the quality of dwellings deeply influences the identity of a city or neighbourhood. Nowadays a greater attention is given to energy conservation, efficiency in buildings and sustainable design, which also result in the increasing need for technological solutions able to generate energy-efficient improvement in the existing building stock. The energy building retrofitting strategy here proposed aims at tackling the problem of energy retrofitting, by a combination of innovative instruments and tools. The methodology framework is based on the comparative analysis on the performance of multiple envelope solutions that have been tested and combined in different building types in the case study of a large urban district, the Corticella neighbourhood in the north of Bologna. This on going experimental project involves social participation of dwellers in the retrofitting activities; the Architecture Department of Bologna University is working together with the Department of Sociology and Building Physics to set up a direct and active cooperation looking for socio-sustainable solution that can also determine an effective improvement in the energy performance of the buildings’ envelopes. Several design options have been studied for the existing buildings, proposing a structure for expansion and adds-on to be added in different time and space, according to the different users’ needs or requirements, exploring the potential links between technologies and urban dwellers in particular contexts of use [1]. The “Abacus” of possible technologies represents a potential innovative tool collecting all the different design options and determining, for each option, the evaluation in terms of energy performance improvement, cost estimations, cost-benefit analysis, social preferences’ indicators. Keeping into account the high degree of variability of the different contexts and buildings asking for energy renovation, it is suggested to apply a different, integrated approach; the here proposed design research study suggests a multiple and modular system allowing customised and tailored solutions, which would ensure a higher level of adaptability, durability and efficiency. Notably, some of Europe’s leading innovation Nations have included user-driven innovation as a way of providing innovative products and services that correspond better to user needs [2]. Thus, the proposed methodology intends to incorporate in the design process specificities of both building type and users’ needs, searching for the solution that best fit within the specific social and environmental context (tailored retrofitting), by neglecting the use of universal and over imposed solutions and accepting the variability and indeterminacy of flexibility and adaptability, in a longer term retrofitting scenarios.

Two heavy rain events over the Central Mediterranean basin, which are markedly different by genesis, dimensions, duration, and intensity, are analyzed. Given the relative low frequency of this type of severe storms in the area, a synoptic analysis describing their development is included. A multispectral analysis based on geostationary multifrequency satellite images is applied to identify cloud type, hydrometeor phase, and cloud vertical extension. Precipitation intensity is retrieved from (i) surface rain gauges, (ii) satellite data, and (iii) numerical model simulations. The satellite precipitation retrieval algorithm 183-Water vapor Strong Lines (183-WSL) is used to retrieve rain rates and cloud hydrometeor type, classify stratiform and convective rainfall, and identify liquid water clouds and snow cover from the Advanced Microwave Sounding Unit-B (AMSU-B) sensor data. Rainfall intensity is also simulated with theWeatherResearch and Forecasting (WRF) numerical model over two nested domains with horizontal resolutions of 16 km (comparable to that of the satellite sensor AMSU-B) and 4 km. The statistical analysis of the comparison between satellite retrievals and model simulations demonstrates the skills of both methods for the identification of the main characteristics of the cloud systems with a suggested overall bias of the model toward very low rain intensities. WRF (in the version used for the experiment) seems to classify as low rain intensity regions those areas where the 183-WSL retrieves no precipitation while sensing amixture of freshly nucleated cloud droplets and a large amount ofwater vapor; in these areas, especially adjacent to the rain clouds, large amounts of cloud liquid water are detected. The satellite method performs reasonably well in reproducing the wide range of gauge-detected precipitation intensities. A comparison of the 183-WSL retrievalswith gauge measurements demonstrates the skills of the algorithm in discriminating between convective and stratiform precipitation using the scattering and absorption of radiation by the hydrometeors.

The key objective of the project "Use of the MSG SEVIRI channels in a combined SSM/I, TRMM and geostationary IR method for rapid updates of rainfall" is the development of algorithms for rapid-update of satellite rainfall estimations at the geostationary (GEO) scale. The new channels available with the Spinning Enhanced Visible and Infrared Imager (SEVIRI) radiometer in the visible (VIS), near infrared (NIR) and infrared (IR) portions of the spectrum provide new insights into the microphysical and dynamic structure of precipitating clouds thus allowing for a more precise identification of precipitation intensities. Passive microwave (PMW) radiometers on board low Earth orbiting (LEO) satellites are used to determine information on the vertical cloud structure. Key features of the new method(s) are: 1. Microphysical characterization of precipitating clouds with VIS/IR sensors; 2. Creation of cloud microphysical and radiative databases from cloud model outputs and aircraft penetrations; 3. Tuning of PMW algorithms for different cloud systems (maritime, continental, convective, stratiform,...); 4. Combination of data from different algorithms and application to a rapid updatecycle at the GEO scale. The project provided the background for EURAINSAT "European Satellite Rainfall Estimation and Monitoring at the Geostationary Scale", a research project co-funded by the Energy, Environment and Sustainable Development Programme of the European Commission within the topic "Development of generic Earth observation technologies". The project web site is accessible at http://www.isac.cnr.it/~eurainsat/. Moreover, it has represented the European framework for the launch of the International Precipitation Working Group (IPWG). A brief account of the major research and organizational results will be given in the following.

Cirrus clouds often form on top of intense convective storms and influence the radiation exchange at the top of the atmosphere. From time to time these cirrus assume a typical plume form, whose origin is yet to be clearly explained. Investigation on plume’s structure and composition is necessary using satellite observations and radiative transfer modeling, since in situ measurements are generally not available for the storm’s extreme scenarios. Plumes of ice crystals produce a significant increase of cloud top reflectivity in channel 3 (3.55 - 3.93 ¼m) of NOAA AVHRR, due to the small size of the crystals (of the order of the channel wavelength). AVHRR measurements over a severe storm are compared with radiative transfer simulations through a 1-D, plane-parallel radiative transfer model. The hydrometeor vertical distribution of a cumulonimbus tower is assumed, composed of a water droplet layer underlying an ice crystal layer. The presence of the plume on top of the cumulonimbus is simulated by an ice crystal layer whose optical depth and ice crystal size and habit are varied. The results of the comparisons show that channel 3 conveys relevant information on the ice crystal size and habit.

Upgrading the environmental and energy performance of existing buildings has taken in recent years a central role in the issues related to sustainability and energy saving. More than 75% of the energy consumed for heating and air-conditioning is essentially wasted due to inefficient insulation wrap, poor sealing of windows and poor performances of the plants’ system. The identification of the most appropriate retrofitting options is a topic of outstanding importance given the potential costs and impacts involved. To ensure replicable results across the EU context, the research methodology presented in this paper is based on the assumption that the solution has to be found in a multi-disciplinary process applicable to almost all the possible scenarios. Standardized interventions are not the effective and sustainable solutions that we are looking for, pre-made receipts are generally addressed towards one main issue are partly effective and not efficient considering the life cycle of the building. The aim is to combine technologies and design tools in one integrated process: 1) Offering an interesting payback time. 2) Increasing the energy performances of the envelope through variable solutions which increase the participation of the users. 3) Overcoming the existing socio-economic barriers.

Developing new sustainable approaches to the dwelling in the contemporary world of architecture is becoming more and more fundamental. If the Candilis revolution was based on humanism and regionalism, the current reaction should focus its attention on the roles of energy and environmental re-qualification of existing buildings according to socio-oriented and multicultural perspectives, by a more appropriate use of technological options in architecture and urban/spatial planning. In this context, if technology has already occupied a main role in the design process, however it is not in the case of a multicultural approach. What the modernists started to call ‘Habitat’ was intrinsic to the society they were working for. The project was designed with regards to only one singular habitat, with one use for society. We developed that functionally oriented approach and have continued to use this mono perspective. It is now necessary to shift the analysis and the research from one singular point of view to multi-fold approaches, in order to expand research in architecture to incorporate the voices of many in a user-driven, bottom-up design approach. The presented strategies for urban and technological retrofitting within two different European contexts, Utrecht and Bologna, try to find possible solutions and suggest a multi-fold approach that could stimulate the process of renewal according to a socio-oriented use of technology in urban environments. Although the approach is based on these two case studies, the underlying principles will be applicable to other districts and other cities as well.