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âItâs just housesâ: the role of community space in a new housing development in the digital era
This paper explores the role played by social media and physical community space in creating community identity in a new residential area. It argues that physical space still matters in a digital era, as social media tends to draw similar people together, rather than building bridges between diverse groups of residents. To build community identity that is both cohesive and inclusive, it is important that community space is available from early on in a building programme
The link between catchment precipitation forecast skill and spread to that of downstream ensemble hydrological forecasts
Operational rainfall and flood forecasting systems across the world are increasingly using ensemble approaches.
Such systems are operated by the Flood Forecasting Centre (FFC) and Scottish Flood Forecasting Service (SFFS)
across Great Britain producing ensemble gridded hydrological forecasts for the next 5-6 days. In order to maximise
the practical day-to-day use of these systems for decision-making and warning, duty hydro-meteorologists require
a sound understanding of both the meteorological and hydrological ensemble forecast skill. In this work, a
common verification framework is defined and used in order to understand the relative levels of skill in both
rainfall and river flow forecasting systems.
A blended 24-member ensemble precipitation forecast, produced by the Met Office, is used to drive the
operational distributed hydrological model in ensemble mode. The hydrological forecasts provide output every
15 minutes out to 6 days on a 1km grid. The blended rainfall forecast is a mixture of the 2.2 km MOGREPS-UK
ensemble up to 36h and the 32 km global MOGREPS-G ensemble at longer lead-times. The forecasts are
interpolated on to a common 2 km grid and the hydrological model used is the Grid-to-Grid model (G2G)
developed by the Centre for Ecology & Hydrology. To establish an upper bound on skill, assessments over a daily
lead-time interval are studied first, and will be the focus here. Spatial and regional variations in forecast skill are
compared between the precipitation (e.g. daily accumulations) and the river flow forecasts. Also of interest is the
impact of catchment size and how to pool and present the skill metrics in a meaningful way for end-users. For
precipitation, the impact of observation type: gridded gauge-only analyses and a radar-derived (gauge calibrated)
precipitation product, is compared to quantify the uncertainty that comes from the observations. Of particular
interest is understanding how the spread in the precipitation forecast is modulated by the downstream hydrological
model. Is it inflated, does it remain comparable, or is it reduced? The work aims to establish the basis for a
real-time monitoring tool that can assist hydro-meteorologists in their interpretation of operational ensemble
forecasts, and facilitate associated decision making processes
Single-Blind, Prospective, Randomized Study of Cefmetazole and Cefoxitin in the Treatment of Postcesarean Endometritis
Objective: The purpose of this study was to compare the clinical efficacy and safety of cefmetazole
given by IV push with that of parenterally administered cefoxitin for the treatment of endometritis following cesarean delivery
Rainfall and river flow ensemble verification: Phase 2. Final report
This document is the Final Report for the âRainfall and River Flow Ensemble Verification: Phase 2â (EnsVerP2) project forming part of the project âImproving confidence in Flood Guidance through verification of rainfall and river flow ensemblesâ. Forecasting the weather and floods is a challenging task and inherently uncertain. Acknowledging and accounting for the uncertainty in precipitation and flood forecasts has become increasingly important. This has partly been driven by the move of warning and guidance services to risk-based approaches that combine the likelihood of flooding with its potential impact on society and the environment. In the UK, such risk-based approaches underpin the National Severe Weather Warning Service delivered by the Met Office, and the Flood Guidance Statements produced by the Flood Forecasting Centre (FFC) and Scottish Flood Forecasting Service (SFFS).
A standard approach to accounting for forecast uncertainty is to use ensemble methods. For a number of years, FFC and SFFS have used precipitation ensembles coupled with the national Grid-to-Grid (G2G) model of river flow to underpin the Flood Guidance Statement. However, the performance of the overall end-to-end ensemble precipitation and river flow forecasting system is currently not verified routinely. This ensemble verification information and evidence is essential: its absence can limit end-user confidence and inhibit full exploitation for flood-risk guidance. In addition, the local flood forecasting systems - used by the Environment Agency (EA), Scottish Environment Protection Agency (SEPA) and Natural Resources Wales (NRW) - are planned to transition to ensemble forecasting and will have similar requirements for verification information.
A first step in addressing this operational gap has been to bring together existing expertise in meteorological and hydrological model performance assessment to design and develop a new, holistic Ensemble Verification Framework. Then to consider how this Framework could be used to develop an operational end-end interactive Ensemble Forecast Visualisation and Verification System. The Framework has been designed so that the operational system developed from it would help forecasters answer the following two key questions.
⢠How well has the ensemble precipitation and flood forecasting system performed in the (recent) past? Particularly for flood events of interest.
⢠What does this mean for interpreting todayâs forecast?
Forecasters could then make more informed decisions and increase their confidence in the use of ensembles for forecasting the severity and likelihood of precipitation and flooding.
To develop and test the potential verification approaches and operational displays, 16-months of precipitation and river flow ensemble forecasts have been processed and verified. Specific case-studies, identified with the help of stakeholders, have been used to prototype, demonstrate, assess and refine the verification tools. The Best Medium Range (BMR) precipitation ensemble is used as input to the national-scale G2G model of river flow across Great Britain and to a small selection of catchment-scale PDM local models of river flow. This approach has allowed rigorous scientific exploration of how to provide robust verification statistics of the ensemble precipitation inputs to the river flow modelling and of its ensemble river flow outputs.
The scientific analysis allowed identification of several points relevant to the underpinning verification methodology part of the Framework.
⢠Three different precipitation accumulation time-intervals were evaluated: 15 min (the temporal resolution of the river flow model and its precipitation inputs), hourly and daily. Daily precipitation accumulations appear to provide the best guidance in terms of rain volume for hydrological impacts. One reason for this may well be because it removes the impact of timing errors at the sub-daily scale. Sub-daily precipitation can be more closely related to river flow on an ensemble member-by-member basis.
⢠The source of observed precipitation (raingauge, radar or merged raingauge-radar) has an impact on the verification analyses and G2G river flow performance.
⢠The change in precipitation-intensity characteristics with lead-time between the STEPS, MOGREPS-UK and MOGREPS-G components of the BMR precipitation ensemble, are evident in both rainfall and river flow analysis.
⢠The length of period used for ensemble verification is an important factor: generally longer than two years is recommended if possible. The 16-month test period was sufficient for generating enough precipitation threshold-exceedances for the 95th percentile thresholds: but insufficient for higher thresholds and for considering river flow thresholds above one half the median annual maximum flood at sub-regional scales.
⢠New methods of presenting the precipitation forecast probabilities have been developed for precipitation thresholds that are hydrologically relevant. The verification of these Time-Window Probabilities (TWPs) has shown that the probabilities are larger, and also more reliable: so users can have greater confidence in using them.
For new real-time displays to be of value in operational settings, it is important that users (e.g. FFC hydrometeorologists or flood forecasting officers) find the displays understandable and easy to deploy in support of flood guidance and warning. Operational users have been engaged in co-design of the real-time forecast displays through the Project Board and a Workshop. These interactions have identified that the real-time displays need to be flexible and informative, with varying layers of detail. Viewing the precipitation and river flow together, however, is the most important ingredient along with using common methods for conveying information on both. Prototype joint rainfall and river flow displays have been created. Further co-design of interactive displays is recommended during future implementation and interactions should include operational users, researchers and system developers.
Case-studies have been used to highlight the potential benefits of these new real-time displays. They have demonstrated how the ensemble verification information can help users make more informed decisions when ensemble verification information is included. For example, knowing whether a forecast is over- or under-confident for different lead-times and severity-thresholds can be very helpful, particularly in marginal cases. That is if a forecast has a tendency to predict too high or low a probability of precipitation, or of river flow, exceeding a given level of severity.
Summary and key recommendation:
Realising the benefit and value of probabilistic flood-risk information for decision-making was a key motivator for the âRainfall and River Flow Ensemble Verification: Phase 2â project. The project succeeded in bringing together the meteorology and hydrology to define, test and demonstrate a joint Ensemble Verification Framework for ensemble precipitation and river flow forecasts. The outcomes of the project demonstrate how the subsequent verification information can be used to enhance the userâs perception and ability to deploy ensemble forecasts and derived probabilities in day-to-day flood risk decision-making.
Overall, the key finding is that joint precipitation and river flow ensemble verification is possible and useful. The primary recommendation is that an end-to-end interactive Ensemble Forecast Visualisation and Verification System for FFC (and SFFS) be implemented as soon as is practicable. The Ensemble Verification Framework provides the blueprint for the system and the Joint Coding Framework developed and applied here provides the basis for the algorithm and code. A detailed set of recommendations have been provided, including what is required for operational implementation. This also includes a priority list of recommendations for developing a minimum system.
The proposed system would address the current urgent operational gap in ensemble forecast verification capability for FFC and SFFS. It would mark a significant addition to the forecastersâ toolkit by providing real-time displays that incorporate ensemble verification information for the first time, and in a usable form. In turn, this will facilitate enhanced and more informed decision-making at times of potential flood-risk. Local model systems have ensemble and probabilistic flood forecasting as an aspiration in their future plans. These systems would eventually benefit from the operationally urgent developments recommended here for the national-scale G2G model used by FFC and SFFS. Local model users could play an early and active part in system co-design as part of a staged implementation process for local model systems
Disturbanceâmediated changes to boreal mammal spatial networks in industrializing landscapes
Funding: InnoTech Alberta. Grant Number: C2021000986; Alberta Innovates; Alberta Conservation Association; Petroleum Technology Alliance Canada. Grant Numbers: 17-ERPC-02, 18-ERPC-01, 19-ERPC-04; Algar Caribou Habitat Restoration Program. Grant Number: NXC-107980; Oil Sands Monitoring program; Natural Sciences and Engineering Research Council of Canada. Grant Numbers: RGPIN-2018â03958, Canada Research Chairs.Compound effects of anthropogenic disturbances on wildlife emerge through a complex network of direct responses and species interactions. Landâuse changes driven by energy and forestry industries are known to disrupt predatorâprey dynamics in boreal ecosystems, yet how these disturbance effects propagate across mammal communities remains uncertain. Using structural equation modeling, we tested disturbanceâmediated pathways governing the spatial structure of multipredator multiprey boreal mammal networks across a landscapeâscale disturbance gradient within Canada's Athabasca oil sands region. Linear disturbances had pervasive direct effects, increasing site use for all focal species, except black bears and threatened caribou, in at least one landscape. Conversely, block (polygonal) disturbance effects were negative but less common. Indirect disturbance effects were widespread and mediated by caribou avoidance of wolves, tracking of primary prey by subordinate predators, and intraguild dependencies among predators and large prey. Contextâdependent responses to linear disturbances were most common among prey and within the landscape with intermediate disturbance. Our research suggests that industrial disturbances directly affect a suite of boreal mammals by altering forage availability and movement, leading to indirect effects across a range of interacting predators and prey, including the keystone snowshoe hare. The complexity of networkâlevel direct and indirect disturbance effects reinforces calls for increased investment in addressing habitat degradation as the root cause of threatened species declines and broader ecosystem change.Peer reviewe
Towards operational joint river flow and precipitation ensemble verification: considerations and strategies
Operational rainfall and flood forecasting systems across the world are increasingly using ensemble approaches.
In Britain such systems are operated by the Flood Forecasting Centre (FFC) over England & Wales and by the
Scottish Flood Forecasting Service (SFFS) over Scotland producing ensemble gridded hydrological forecasts
out to 5 or 6 days. In order to maximise the practical day-to-day use of these systems for flood guidance and
warning, duty hydrometeorologists require a sound understanding of both the meteorological and hydrological
ensemble forecast skill. To help meet this requirement, a common framework for the verification of river flow
and precipitation ensembles is developed and demonstrated over Britain for eventual use in an operational flood
forecasting setting.
The river flow ensembles are obtained from the distributed hydrological model Grid-to-Grid (G2G), configured
with national coverage on a 1 km grid and using an ensemble of 15 minute precipitation accumulations as
input. The precipitation ensemble consists of operational Numerical Weather Prediction (NWP) forecasts from the
Met Office Unified Model. Given the different physical characteristics of river flow and catchment precipitation,
and differences in forecast verification methodologies routinely employed by the hydrological and meteorological
communities, key considerations for the common verification framework are identified and investigated. These
include the appropriateness of different precipitation accumulation periods given timing errors and hydrological
response times, the operationally relevant use of river flow and rainfall thresholds for contingency tables and skill scores based on them, and the effects of precipitation observation error on verification.
The practical challenges of verification using a limited record of precipitation ensembles, from a system
only relatively recently made operational, are highlighted. Methods of obtaining more robust verification statistics,
given the available ensembles, are presented and demonstrated for example periods in December 2015. At the
regional scale, both river flow and precipitation verification results are shown to be dependent on the locations considered and related to variations in precipitation totals. For river flows, catchment size is found to be a key influence on ensemble performance. It is demonstrated how this behaviour can be used to obtain more-robust river flow verification statistics at sub-regional scales
Catchment-based precipitation and river flow ensemble forecast skill in the presence of observation uncertainty
The use of ensemble forecasts in operational rainfall and flood forecasting systems is rapidly increasing. In the
UK, such systems are operated by the Flood Forecasting Centre (FFC) and Scottish Flood Forecasting Service
(SFFS) producing ensemble gridded hydrological forecasts out to 6 days. In order to maximise the practical
day-to-day use of these systems, for decision-making and warning, duty hydrometeorologists require a sound
understanding of both the meteorological and hydrological ensemble forecast skill.
A blended Met Office 24-member ensemble precipitation forecast â a mixture of the STEPS nowcast ensemble
and STEPS-blended 2.2 km MOGREPS-UK ensemble and 32 km global MOGREPS-G ensemble â drives the
Grid-to-Grid (G2G) distributed hydrological model developed by the Centre for Ecology & Hydrology (CEH).
G2G uses 15-minute precipitation accumulations as input, and produces river flows at 15-minute intervals on a
1km grid.
Phase 1 of the investigation, completed in 2017, formulated and demonstrated a common rainfall and river flow
ensemble verification framework. The results gave an initial appreciation of the relative levels of skill in both
ensemble rainfall and river flow forecasting systems. In 2018, the verifications of daily and hourly precipitation accumulations
will be extended to use 15-minute accumulations. Verifications for three forecast time-horizons â Day
1, Days 2-3 and Days 4-6 â will also be demonstrated. In Phase 1, the sensitivity of verification measures to observation
type was illustrated by comparing scores based on radar-only and raingauge-only analyses. Here, in Phase
2, theoretical principles discussed by Ferro (2017) are explored to determine whether a practical application of the
theory is possible to gain a more robust measure of forecast performance in the presence of observation uncertainty.
Reference
Ferro, C.A.T. 2017. Measuring forecast performance in the presence of observation error. Q. J. R. Meteorol. Soc.,
143, 2665-2676
Priorities of Low-Income Urban Residents for Interventions to Address the Socio-Economic Determinants of Health
ObjectivesâTo determine the priorities of low-income urban residents for interventions that
address the socio-economic determinants of health.
MethodsâWe selected and estimated the cost of 16 interventions related to education, housing,
nutrition, employment, health care, healthy behavior, neighborhood improvement, and
transportation. Low-income residents of Washington, D.C. (N=431) participated in decision
exercises to prioritize these interventions.
ResultsâGiven a budget valued at approximately twice an estimated cost of medical and dental
care ($885), the interventions ultimately prioritized by the greatest percentage of individuals were:
health insurance (95%), housing vouchers (82%) dental care (82%), job training (72%), adult
education (63%), counseling (68%), healthy behavior incentives (68%), and job placement (67%).
The percentages of respondents who received support for housing, adult education, and job
training and placement were far less than the percentage who prioritized these interventions.
ConclusionsâPoor and low-income residentsâ priorities may usefully inform allocation of
social services that affect health
'Public reason', judicial deference and the right to freedom of religion and belief under the Human Rights Act 1998
Effects of extreme natural events on the provision of ecosystem services in a mountain environment : The importance of trail design in delivering system resilience and ecosystem service co-benefits
A continued supply of ecosystem services (ES) from a system depends on the resilience of that system to withstand shocks and perturbations. In many parts of the world, climate change is leading to an increased frequency of extreme weather events, potentially influencing ES provision. Our study of the effects of an intense rainfall event in Gorce National Park, Poland, shows: (1) the intense rainfall event impacted heavily on the supply of ES by limiting potential recreation opportunities and reducing erosion prevention; (2) these negative impacts were not only restricted to the period of the extreme event but persisted for up to several years, depending on the pre-event trail conditions and post-event management activities; (3) to restore the pre-event supply of ES, economic investments were required in the form of active repairs to trails, which, in Gorce National Park, were an order of magnitude higher than the costs of normal trail maintenance; and (4) when recreational trails were left to natural restoration, loss of biodiversity was observed, and recovery rates of ES (recreation opportunities and soil erosion prevention) were reduced in comparison to their pre-event state. We conclude that proper trail design and construction provides a good solution to avoid some of the negative impacts of extreme events on recreation, as well as offering co-benefits in terms of protecting biodiversity and enhancing the supply of regulating services such as erosion prevention
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