The GirlStars Program: Challenges to Recruitment and Retention in a Physical Activity and Health Education Program for Adolescent Girls Living in Public Housing

BACKGROUND. Although physical inactivity is a concern for all adolescents, physical activity levels are especially low among minority adolescents and minimal among girls from low-income families. After-school programs can reduce high-risk behaviors and strengthen schools, families, and communities. CONTEXT. We conducted an operational research project that provided free access to a program of regular, organized physical activity combined with health education sessions for adolescent girls in 2 public housing developments in Boston, Massachusetts. METHODS. From July 2002 through October 2005, at each of 2 public housing sites, the GirlStars program participants met each week for two 2-hour sessions, 1 dedicated to physical activity and 1 dedicated to health education. Sessions were led by the project coordinator and a resident assistant at each development. OUTCOME. Participants in the GirlStars program increased their health knowledge, self-confidence, and decision-making skills, but rates of participation were low. Factors that affected participation included safety concerns, lack of community support for the program, interpersonal conflicts, attrition in staff, and conflicts with other activities. INTERPRETATION. Programs in public housing developments that address these barriers to recruitment and retention may be more successful and reach more girls

Maternal mental health research in Malawi: Community and healthcare provider perspectives on acceptability and ethicality

Maternal mental health (MMH) is recognised as globally significant. The prevalence of depression and factors associated with its onset among perinatal women in Malawi has been previously reported, and the need for further research in this domain is underscored. Yet, there is little published scholarship regarding the acceptability and ethicality of MMH research to women and community representatives. The study reported here sought to address this in Malawi by engaging with communities and healthcare providers in the districts where MMH research was being planned. Qualitative data was collected in Lilongwe and Karonga districts through 20 focus group discussions and 40 in-depth interviews with community representatives and healthcare providers from January through April 2021. All focus groups and interviews were audio recorded, transcribed verbatim (in local languages Chichewa and Tumbuka), translated into English, and examined through thematic content analysis. Participants' accounts suggest that biopsychosocial MMH research could be broadly acceptable within the communities sampled, with acceptability framed in part through prior encounters with biomedical and public health research and care in these regions, alongside broader understandings of the import of MMH. Willingness and consent to participate do not depend on specifically biomedical understandings of MMH, but rather on familiarity with individuals regarded as living with mental ill-health. However, the data further suggest some ‘therapeutic misconceptions’ about MMH research, with implications for how investigations in this area are presented by researchers when recruiting and working with participants. Further studies are needed to explore whether accounts of the acceptability and ethicality of MMH research shift and change during and following research encounters. Such studies will enhance the production of granular recommendations for further augmenting the ethicality of biomedical and public health research and researchers' responsibilities to participants and communities

Rainfall simulations of high-impact weather in South Africa with the conformal cubic atmospheric model (CCAM)

Warnings of severe weather with a lead time longer that two hours require the use of skillful numerical weather prediction (NWP) models. In this study, we test the performance of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Conformal Cubic Atmospheric Model (CCAM) in simulating six high-impact weather events, with a focus on rainfall predictions in South Africa. The selected events are tropical cyclone Dineo (16 February 2017), the Cape storm (7 June 2017), the 2017 Kwa-Zulu Natal (KZN) floods (10 October 2017), the 2019 KZN floods (22 April 2019), the 2019 KZN tornadoes (12 November 2019) and the 2020 Johannesburg floods (5 October 2020). Three configurations of CCAM were compared: a 9 km grid length (MN9km) over southern Africa nudged within the Global Forecast System (GFS) simulations, and a 3 km grid length over South Africa (MN3km) nudged within the 9 km CCAM simulations. The last configuration is CCAM running with a grid length of 3 km over South Africa, which is nudged within the GFS (SN3km). The GFS is available with a grid length of 0.25 , and therefore, the configurations allow us to test if there is benefit in the intermediate nudging at 9 km as well as the effects of resolution on rainfall simulations. The South AfricanWeather Service (SAWS) station rainfall dataset is used for verification purposes. All three configurations of CCAM are generally able to capture the spatial pattern of rainfall associated with each of the events. However, the maximum rainfall associated with two of the heaviest rainfall events is underestimated by CCAM with more than 100 mm. CCAM simulations also have some shortcomings with capturing the location of heavy rainfall inland and along the northeast coast of the country. Similar shortcomings were found with other NWP models used in southern Africa for operational forecasting purposes by previous studies. CCAM generally simulates a larger rainfall area than observed, resulting in more stations reporting rainfall. Regarding the different configurations, they are more similar to one another than observations, however, with some suggestion that MN3km outperforms other configurations, in particular with capturing the most extreme events. The performance of CCAM in the convective scales is encouraging, and further studies will be conducted to identify areas of possible improvement.The AIMS NEI Women in Climate Change Science (WiCCS) fellowship and the Water Research Commission.https://www.mdpi.com/journal/atmospheream2023Geography, Geoinformatics and Meteorolog

The influence of topography and model grid resolution on extreme weather forecasts over South Africa

The topography of South Africa (SA) shows complex variations and is one the main factors that determine the daily weather patterns and climate characteristics. It affects for example temperature, winds and rainfall (intensity and distribution). Mesoscale numerical weather prediction (NWP) models are used to simulate atmospheric motions with high horizontal grid resolution using appropriate cumulus parameterisation schemes. They also allow users to investigate the effects of topography and surface heating on the development of convective systems. The Weather Research and Forecasting (WRF) model was applied over the complex terrain of SA to simulate extreme weather events and evaluate the influence of topography and grid resolution on the accuracy of weather simulations. This includes heavy precipitation event that lead to floods over Limpopo region of SA which was caused by the tropical depression Dando for the period 16 -18 January 2012; the heat wave events over Limpopo region for the period 22-26 October 2011 and also over Cape region for the period 15-18 January 2012. The Grell-Devenyi Ensemble (GDE) cumulus parameterization scheme was applied. The WRF model was run at a horizontal resolution of 9 km with 3 km nests, one over Limpopo and another over Cape region respectively. A total of 210 South African Weather Service (SAWS) synoptic stations data were used to verify the model, with 37 stations located over Limpopo and 88 over Cape region. The WRF model simulations are able to capture the spatial and temporal distribution of the heat wave over Limpopo and Cape regions respectively. The model verification with observational data showed that the performance statistics are in the expected range. The experiments without topography give unrealistic verification scores. The increase of model grid resolution from 9 to 3 km improved the spatial and temporal distribution and performance statistics. The above findings are in general similar for the two heat wave events, although the influence of topography over Cape region is not too pronounced. This can be attributed to different topographic variations over the Cape region as compared to the Limpopo region. The WRF model captured well the spatial and temporal distribution of rainfall patterns; verification statistics shows over-prediction of its intensity in simulation with topography. The simulation without topography shows unrealistic space and intensity of rain distribution. An increase in model grid resolution from 9 to 3 km shows improved spatial and temporal distribution of rainfall. The importance of high grid resolution and the use of non-hydrostatic equations are confirmed by the analysis of the vertical velocity distribution and moisture fluxes. The overall findings proved that topography plays a major role to weather and climate over SA. The high grid resolution allows for a better topography representation and capturing convective activities by the use of nonhydrostatic approximations. Therefore the WRF model proved to be useful forecasting tool for weather and climate simulations and can be used for operational weather forecasting over South Africa.Dissertation (MSc)--University of Pretoria, 2014.lk2014Geography, Geoinformatics and MeteorologyMScUnrestricte

Model inter-comparison for short-range forecasts over the southern African domain

Numerical weather prediction (NWP) models have been increasing in skill and their capability to simulate weather systems and provide valuable information at convective scales has improved in recent years. Much effort has been put into developing NWP models across the globe. Representation of physical processes is one of the critical issues in NWP, and it differs from one model to another. We investigated the performance of three regional NWP models used by the South African Weather Service over southern Africa, to identify the model that produces the best deterministic forecasts for the study domain. The three models – Unified Model (UM), Consortium for Small-scale Modelling (COSMO) and Weather Research and Forecasting (WRF) – were run at a horizontal grid spacing of about 4.4 km. Model forecasts for precipitation, 2-m temperature, and wind speed were verified against different observations. Snow was evaluated against reported snow records. Both the temporal and spatial verification of the model forecasts showed that the three models are comparable, with slight variations. Temperature and wind speed forecasts were similar for the three different models. Accumulated precipitation was mostly similar, except where WRF captured small rainfall amounts from a coastal low, while it over-estimated rainfall over the ocean. The UM showed a bubble-like shape towards the tropics, while COSMO cut-off part of the rainfall band that extended from the tropics to the sub-tropics. The COSMO and WRF models simulated a larger spatial coverage of precipitation than UM and snow-report records.Significance: Extreme weather events, such as tornadoes, floods, strong winds and heat waves, have significant impacts on society, the economy, infrastructure, agriculture and many other sectors. These impacts may be mitigated or even prevented through early warning systems which depend on the use of weather forecasts and information from NWP models. As South Africa depends on models from developed countries, these models may have shortcomings in capturing extreme weather events over the southern African region

Synoptic structure of a sub-daily extreme precipitation and flood event in Thohoyandou, north-eastern South Africa

An extreme sub-daily precipitation event produced about 300 mm of rainfall in less than 4 h overnight from 13–14 February 2019 resulting in high floods in Thohoyandou, a small town northeast of South Africa. We employed station, radar, satellite and reanalysis datasets to investigate the rainfall, circulation and thermodynamic fields and understand the meteorological structure of the extreme event via a multiscale analysis. The large-scale synoptic environment was characterized by a mid-tropospheric tropical-temperate trough and attendant cloud band coupled to a surface high ridging over the southeast coast of the country. We found that whilst heavy rainfall (>50 mm/24 h) was widespread ahead of the upper trough, extreme amounts (∼100 mm/h) were localized due to a cloudburst. A small perturbation to the favorable large scale mid-tropospheric environment also contributed to localized heavy rainfall. The south-north pressure gradient was steepened by a surface low over southern Mozambique resulting in enhanced moisture fluxes deriving from the southwest Indian Ocean. The interaction of prevailing surface winds and a low-level jet with the steep topography of the adjacent Soutpansberg Mountain Range enhanced low-level convergence and lifting in the area. We also show that the highest rainfalls were uphill of the location of flooding which was contained in a poorly drained valley. Whereas the Unified Model forecasts appeared accurate for the large-scale pattern of heavy rainfall in the area, the rainfall peak was generally underestimated, whilst the timing of extreme rainfall was delayed in the 18Z simulation, which is used by forecasters operationally. Our findings contribute to understanding the occurrence of extreme weather events over northeastern South Africa and also how models treat them, towards natural disaster risk reduction

Simulation of the eThekwini Heat Island in South Africa

The study evaluates the performance of the Conformal Cubic Atmospheric Model (CCAM) when simulating an urban heat island (UHI) over the city of eThekwini, located along the southeast coast of South Africa. The CCAM is applied at a grid length of 1 km on the panel with eThekwini, in a stretched-grid mode. The CCAM is coupled to the urban climate model called the Australian Town Energy Budget (ATEB). The ATEB incorporates measured urban parameters including building characteristics, emissions, and albedo. The ATEB incorporates the land-cover boundary conditions obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite. The CCAM configuration applied realistically captured the orientation of the city and land-cover types. Simulations of meteorological variables such as temperatures and longwave radiation reproduced the spatial distribution and intensity of the UHI. Results show that the UHI is stronger during summer and weaker in all other seasons. The UHI developed because of natural factors (e.g., distribution of longwave radiation) and human factors (e.g., urban expansion, an increase in anthropogenic emissions, and additional heating). Because of the city’s location along the coast, the UHI simulation could be weakened by atmospheric circulations resulting from land and sea breezes. Mitigation methods such as applying reflective paints and revegetation of the city may increase albedo and latent heat fluxes but reduce the sensible heat fluxes and weaken the UHI. However, the UHI may not be completely eliminated since natural factors and emissions constantly influence its development. SIGNIFICANCE STATEMENT : The outcome of this study could be particularly valuable for municipalities in their disaster management planning since the occurrence of UHIs can cause heat-related diseases such as heatstrokes and even fatalities, especially for the elderly, in cities. Increases in temperatures also lead to higher demand for air conditioners, which in the long term lead to higher demand and pressure on the electricity grid system as well as increased costs for the individual. As higher temperatures increase heatwave events, increases in anthropogenic emissions also result in degraded air quality that impacts health. UHIs impact human lives and can cause deterioration in health when individuals experience high temperatures in summer. Warmer temperatures also reduce energy demand (and in the long term assist with global environmental restoration).https://journals.ametsoc.org/view/journals/apme/apme-overview.xml2023-11-01hj2023Geography, Geoinformatics and Meteorolog

Convection parametrization and multi-nesting dependence of a heavy rainfall event over Namibia with weather research and forecasting (WRF) model

Namibia is considered to be one of the countries that are most vulnerable to climate change due to its generally dry climate and the percentage of its population that rely on subsistence agriculture for their livelihoods. Early-warning systems are an important aspect of adapting to climate change. Weather forecasting relies on the use of numerical weather prediction models and these need to be configured properly. In this study, we investigate the effects of using multi-nests and a convection scheme on the simulation of a heavy rainfall event over the north-western region of Kunene, Namibia. The event, which was associated with a cut-off low system, was short-lived and resulted in over 45 mm of rainfall in one hour. For the multi-nest, a 9 km grid-length parent domain is nested within the Global Forecast System (GFS) simulations, which in turn forces a 3 km grid spacing child domain. A different set of simulations are produced using a single nest of 3 km grid spacing, nested directly inside the GFS data. The simulations are produced with the convection scheme switched on and off. The impact of a single versus multi-nest is found to be small in general, with slight differences in the location of high rainfall intensity. Switching off the convection schemes results in high rainfall intensity and increased detail in the simulations, including when a grid spacing of 9 km is used. Using a grid spacing of 3 km with the convection scheme on, results in a loss of detail in the simulations as well as lower rainfall amounts. The study shows a need for different configurations to be tested before an optimum configuration can be selected for operational forecasting. We recommend further tests with different synoptic forcing and convection schemes to be conducted to identify a suitable configuration for Namibia.The Climate Research for Development (CR4D) fellowship managed by the African Academy of Sciences and the South African Department of Science and Innovation.http://www.mdpi.com/journal/climatepm2021Geography, Geoinformatics and Meteorolog