Conferência Internacional "CIDADES E ALTERAÇÕES CLIMÁTICAS. QUE FUTURO?", Lisboa, 15-16 Maio 2008

Major urban development and regeneration have been planned in several regions of the UK and elsewhere. The modification of the morphology of the cities expected in the future poses new challenges in various knowledge fields, from building design and city planning to meteorology. The present work reports an investigation of the effects of urban surface heterogeneity on the distribution of sensible heat flux and its impact on convective precipitation, in Greater Manchester. A simple numerical scheme is formulated to derive fields of surface sensible heat flux for a range of wind and temperature values over the urban area. This involves the derivation and mapping of urban surface characteristics in terms of some morphologic aspects such as the height of buildings and the frontal area index. Comparisons are made of the sensible heat flux field with the rainfall field measured using a C-band radar. The possible influence of the urban morphology on the rainfall distribution, and the eventual initiation of convective cells by the sensible heat flux input generated by the high-rise buildings in Manchester city centre, are discussed

Bibliography on hydrological applications of weather radar in the United Kingdom. Eighth edition (publications notified up to December 2011)

This bibliography of UK publications in the field of hydrological applications of weather radar is an update of the one produced in 2009. It has been compiled by the Inter-Agency Committee on the Hydrological Use of Weather Radar, with the help of the NERC Centre for Ecology & Hydrology at Wallingford. The Committee was originally established to provide a forum to foster links between organisations and individuals with expertise in the use of weather radar for hydrological purposes, in particular the users and the research community, and promote additional research and international contacts. The Committee's terms of reference and membership information can be found in Appendices to this document. This 8th edition includes papers from the International Symposium on “Weather Radar and Hydrology” (www.wrah2011.org), published as an IAHS Red Book conference proceedings (IAHS Publ. 351, iahs.info/redbooks/351.htm)

Inter-Agency Committee on the Hydrological Use of Weather Radar. Eighth report 2010 to 2012

As with the previous session report, we open reflecting on a period of significant UK flooding. The Summer and Autumn 2012 floods are still very fresh in the memory of those who have been trying to manage and respond to these events and for some the impacts are still affecting daily lives. Initial estimates indicate that the 2012 summer floods affected 2,700 properties with 70,000 properties receiving flood warnings. No doubt these damages estimates will increase as further information is gathered. However, what has changed from the previous 2007 to 2010 session has been the further development of meteorological and hydrological forecasting approaches and the emergence of hydrometeorology capabilities across England, Wales and Scotland to help improve prediction of these types of events. Radar continues to play an important role in flood risk and water management and the application of emerging science is the focus of this report. At the beginning of this current session, the Committee were keen to promote ways to influence the greater use of weather radar by operating agencies and to highlight areas of improvement and research in support of the user community. Specifically, the Committee wanted to explore various service and system developments, understand various ongoing research areas and their application for hydrology and water management, and promote the role of radar in flood risk management. Section 3 of the Committee report highlights research needs and presents the considerable range of ongoing science developments across various research groups. The approaches to raingauge-radar merging and data assimilation of radar data for Numerical Weather Prediction are presented as are the requirements from an established hydrological and emerging water management community. The requirement to provide forecasting capabilities for the whole of the country and for longer lead times was driven as an outcome of the Pitt Review. In Section 4, the efforts of some agencies in developing these capabilities are presented with emphasis on the development of countrywide grid-based hydrological models. In addition, Section 4 reflects on the largest upgrade to the UK radar network in its 30 year history and the introduction of significant radar capabilities that will benefit the user community once completed. Section 5 presents what has been the main focal point for the Committee’s attention during the session period. Following the Committee’s successful bid to host the International Symposium on Weather Radar and Hydrology, most of the Committee have been in some way involved in the successful delivery of this major event. Held over four days at the University of Exeter, this was the 8th in the symposium series and attracted over 250 international delegates. It is worth highlighting that following the organisation of Weather Radar and Hydrology 2011, the International Association of Hydrological Sciences has now published the conference proceedings as part of their Red Book series. The volume brings together over 100 peer-reviewed papers from the symposium providing a valuable record of the current activity in this field. Finally, the appendices to this session report provide an overview of the UK academic and operational agency activity in this sector

Lung tumour risk in radon-exposed rats from different experiments: Comparative analysis with biologically based models

Data sets of radon-exposed male rats from Wistar and Sprague-Dawley strains have been investigated with two different versions of the two-step clonal expansion (TSCE) model of carcinogenesis. These so-called initiation-promotion (IP) and initiation-transformation (IT) models are named after the cell-based processes that are assumed to be induced by radiation. The analysis was done with all malignant lung tumours taken to be incidental and with fatal tumours alone. For all tumours treated as incidental, both models could explain the tumour incidence data equally well. Owing to its better fit, only the IP model was applied in the analysis of fatal tumours that carry additional information on the time when they cause death. A statistical test rejected the hypothesis that a joint cohort of Wistar and Sprague-Dawley rats can be described with the same set of model parameters. Thus, the risk analysis has been carried out for the Wistar rats and the Sprague-Dawley rats separately and has been restricted to fatal tumours alone because of their similar effect in humans. Using a refined technique of age-adjustment, the lifetime excess absolute risk has been standardised with the survival function from competing risks in the control population. The age-adjusted excess risks for both strains of rats were of similar size, for animals with first exposure later in life they decreased markedly. For high cumulative exposure the excess risk increased with longer exposure duration, for low cumulative exposure it showed the opposite trend. In addition, high cumulative exposure exerted lethal effects other than lung cancer on the rats. © Springer 2004

Interspecies comparison of lung clearance after inhalation of monodisperse, solid cobalt oxide aerosol particles.

An interspecies comparison of the lung clearance of a well-defined inhalable material was conducted to aid in the development of models used to relate inhalation of radioactive particles to organ doses and bioassay measurements, and in particular to aid in the extrapolation of animal data to man. It complements a previous interspecies comparison in which lung clearance of monodisperse, porous 0.8 μm and 1.7 μm diameter cobalt oxide (Co3O4) particles was followed in seven species including man (Bailey et al., J. Aerosol Sci. 20, 169-188, 1989). In the present study baboons, dogs and HMT rats were used since they had shown the most prominent differences in clearance in the previous investigation. Additionally, clearance in the human volunteers and baboons was very similar. The material selected consisted of almost solid, monodisperse 0.9 μm diameter CoP3O4 particles which were chemically similar to the materials studied previously but differed physically with a higher density and a smaller specific surface area. Lung retention and excretion of 57Co were followed for at least six months after inhalation. Lung retention at 6 months after inhalation ranged from 60% of the initial lung deposit in baboons to 5%, in rats and in all three species clearance was considerably slower than that of porous 0.8 μm Co3O4 particles. Lung clearance rates due to translocation of dissociated 57Co to the blood, S(t), and due to particle transport to the GI tract M(t) were calculated. Initially, S(t) ranged from 0.1% of the contemporary lung content day-1 in baboons to 0.7% in rats. Depending on the initial translocation rates of each species, S(t) over time followed patterns expected from a model of particle dissolution derived previously. For each species, a correlation was found between the initial translocation rates and the specific surface area of the three particles used. Estimated values of M(t) were consistent with values obtained previously with other materials

Interspecies comparison of lung clearance after inhalation of monodisperse, solid cobalt oxide aerosol particles.

An interspecies comparison of the lung clearance of a well-defined inhalable material was conducted to aid in the development of models used to relate inhalation of radioactive particles to organ doses and bioassay measurements, and in particular to aid in the extrapolation of animal data to man. It complements a previous interspecies comparison in which lung clearance of monodisperse, porous 0.8 μm and 1.7 μm diameter cobalt oxide (Co3O4) particles was followed in seven species including man (Bailey et al., J. Aerosol Sci. 20, 169-188, 1989). In the present study baboons, dogs and HMT rats were used since they had shown the most prominent differences in clearance in the previous investigation. Additionally, clearance in the human volunteers and baboons was very similar. The material selected consisted of almost solid, monodisperse 0.9 μm diameter CoP3O4 particles which were chemically similar to the materials studied previously but differed physically with a higher density and a smaller specific surface area. Lung retention and excretion of 57Co were followed for at least six months after inhalation. Lung retention at 6 months after inhalation ranged from 60% of the initial lung deposit in baboons to 5%, in rats and in all three species clearance was considerably slower than that of porous 0.8 μm Co3O4 particles. Lung clearance rates due to translocation of dissociated 57Co to the blood, S(t), and due to particle transport to the GI tract M(t) were calculated. Initially, S(t) ranged from 0.1% of the contemporary lung content day-1 in baboons to 0.7% in rats. Depending on the initial translocation rates of each species, S(t) over time followed patterns expected from a model of particle dissolution derived previously. For each species, a correlation was found between the initial translocation rates and the specific surface area of the three particles used. Estimated values of M(t) were consistent with values obtained previously with other materials