Lesley Anne Gibson

Future land cover changes may result in adjustments to biophysical drivers impacting on net ecosystem carbon exchange (NEE), catchment water use through evapotranspiration (ET), and the surface energy balance through a change in albedo. The Land Change Modeller (Idrisi Terrset 18.08) and land cover for 2000 and 2014 are used to create a future scen...

Increasing global urbanisation is leading to a rise in the number of people living in informal settlements, challenging our ability to achieve sustainable development goals. As a consequence of high building density, inadequate building methods and flammable building materials, informal settlements are highly vulnerable to the devastating impacts o...

Aims/hypothesis Our aim was to investigate the geospatial distribution of diabetic foot ulceration (DFU), lower extremity amputation (LEA) and mortality rates in people with diabetes in small geographical areas with varying levels of multiple deprivation. Methods We undertook a population cohort study to extract the health records of 112,231 peopl...

Background: The challenges faced by the Global South during the coronavirus disease (COVID-19) pandemic are compounded by the presence of informal settlements, which are typically densely populated and lacking in formalized sanitation infrastructure. Social distancing measures in informal settlements may be difficult to implement due to the densit...

Wildland-Urban Interface (WUI) fires are becoming more common globally. However, most research has been focused on developed regions such as North America and Australia, exposing a lack of geographical diversity in the field. This paper presents an analysis of South Africa's largest WUI fire disaster, in terms of the number of structures lost and t...

A significant percentage of the urban population in most low- and middle-income countries live in informal settlements. Due to poor quality housing, dense settlement patterns and lack of risk reducing infrastructure, informal settlements are least prepared and at higher risk for climate change issues. Marginalized communities in settlements in the...

As the largest developing country, China has a large number of informal settlements threatened by fire, including shanty towns, urban villages, group rented houses, prefabricated houses and ethnic minority traditional settlements, especially for some ethnic minority traditional settlements in the southwestern region. However, the studies on fire sa...

Fire spread between informal settlement dwellings (ISD) is a primary concern for large scale informal settlements conflagrations. Globally, approximately one billion people live in informal settlements and are exposed to these fires. This paper presents a fire spread experiment between two dwellings, built with ISO 9705 dimension as an approximatio...

Fires in informal settlements are devastating to residents of these precarious urban environments. This paper highlights the use of spatial metrics and wind speed and direction for fire spread risk identification for informal settlement fires in Cape Town. Data on: fire incidents, dwelling footprints, and the wind conditions during a fire, are anal...

According to recent UN reports, it is estimated that more than one billion people live in informal settlements globally, exposing them to a large potential fire risk. In previous research, it was found that the main fire spread mechanism between dwellings is the external flaming (plume) and radiative heat fluxes from the vertical openings at the dw...

Globally, grasslands are under threat from woody encroachment by invasive alien plants and this undermines grass production. The study sought to determine the effects of Acacia mearnsii clearing on soil physico-chemical properties and grass production. Soil samples were collected from three A. mearnsii invasion statuses and analysed for representat...

Approximately one billion people across the globe are living in informal settlements with a large potential fire risk. Due to the high dwelling density, a single informal settlement dwelling fire may result in a very serious fire disaster leaving thousands of people homeless. In this work, a simple physics-based theoretical model was employed to as...

Large conflagrations of informal settlements occur regularly, leaving thousands of people homeless daily and taking tens of thousands of lives annually. Over the past few years, a large amount of data has been collected from a number of full-scale informal settlement fire experiments. This paper uses that data with a semi-probabilistic fire model p...

Sars-CoV-2 is spread through contact between people and an understanding of where people are in contact with each other is necessary to prevent its spread. In this paper, the residential building density of Bulawayo was considered a proxy for high density of people. OpenStreetMap (OSM) building data was downloaded and converted from polygon to poin...

Purpose Globally, over 95% of fire related deaths and injuries occur in low- and middle-income countries. Within informal settlements, the risk of fire resulting in injury or death is particularly high. This paper examines fire risks in informal settlements in New Delhi and Cape Town, and tented informal settlements in Lebanon. Design/methodology/...

Physical inactivity is a global pandemic. The COVID-19 crisis has altered global patterns of physical activity in ways that were unimaginable before the outbreak. Enforced restrictions on mobility and the mass closure of indoor fitness centres has highlighted the limitations of many urban areas for enabling physical activity and reinforced inequali...

Informal settlements are home to approximately one billion people globally and are growing due to rapid urbanisation in less economically developed countries. Their dense layouts, often combined with light, combustible building materials make them highly vulnerable to fires. In some cases fires have spread through hundreds or thousands of homes in...

The risk of fire spread in informal settlements is significant and can be analysed as a function of the spatial arrangement of dwellings. Spatial metrics representing density and shape of dwellings are proposed as a method to identify settlements at high risk of fire spread. LiDAR data is used to map dwelling roofs for informal settlements in the C...

In South Africa alone, there are more than 5000 informal settlement fires a year, where a single incident can leave up to 10000 people homeless. The government and local authorities of countries with informal settlements, that extend over large areas, have no tools to simulate fires to identify high risk areas, or to quantify the magnitude of an in...

UNSTRUCTURED Due to the density of informal settlements, effectively implementing social distancing may be a challenge in informal settlements. This short communication uses dwelling outlines for informal settlements in the City of Cape Town to demonstrate that using a 2 m measure, effective social distancing will be challenging.

Approximately, one billion people across the globe are currently living in informal shack settlements with a large potential fire risk. Due to the small distance between shacks, a single shack fire may spread and could cause a large area of informal settlement to be burnt in a short period of time. In this work, the critical fire separation distanc...

Informal settlement fires occur increasingly in the developing regions and result in a large number of residents dead or homeless in recent years. Inspired by Chinese ancient Ma Tau wall design, a separation wall with small openings and doors is proposed to be built within the informal settlement area to barrier fire spread between dwellings and in...

This fifth edition of the United Nations Global Assessment Report on Disaster Risk Reduction (GAR) is being issued four years after the adoption of the Sendai Framework for Disaster Risk Reduction 2015–2030 (Sendai Framework). Now is a time of heightened global urgency, and the need for ambitious collective action to reduce disaster risk, build res...

The Global Assessment Report on Disaster Risk Reduction (GAR) is the flagship report of the United Nations on worldwide efforts to reduce disaster risk.

Fires in informal settlements are a major risk facing big cities within the developing countries, not only concerning life safety but also because they exert social and economic pressures on these communities. One of the cities most affected by informal settlement fires is Cape Town, Western Cape, South Africa. A research project, namely IRIS-Fire,...

This paper explores the relationship between land cover change and albedo, recognized as a regulating ecosystems service. Trends and relationships between land cover change and surface albedo were quantified to characterise catchment water and carbon fluxes, through respectively evapotranspiration (ET) and net primary production (NPP). Moderate res...

In a context of water scarcity, efforts to increase landscape production should focus on improving water productivity. This requires an appreciation of the various components of evapotranspiration (ET), including soil evaporation (Es) because the latter reflects ‘unproductive’ water loss. Both complex and simple algorithms have been developed to de...

Accurately measuring evapotranspiration (ET) is important in the context of global atmospheric changes and for use with climate models. Direct ET measurement is costly to apply widely and local calibration and validation of ET models developed elsewhere improves confidence in ET derived from such models. This study sought to compare the performance...

An understanding of factors modulating water and energy fluxes partitioning over vegetated surfaces is important in a context of global environmental changes. The study evaluated the patterns of water vapour and energy fluxes to enable the development of biome scale predictive evapotranspiration (ET) models over the Albany Thicket vegetation. Envir...

Land cover change is a pervasive force and it influences the relationship between precipitation (P) and actual evapotranspiration (AET). The study sought to determine variations in catchment scale AET attributable to land cover change over a grassland in the Eastern Cape, South Africa. Remotely sensed rainfall and AET data were used. Land cover map...

This paper introduces the history and role of consultation processes of contemporary planning and, after presenting the popularity and criticisms of different practices including communities in urban decision making, it explores how rational planning tools like the geographic information system (GIS) could be exploited to reshape consultation and f...

Determining the quantum (both annual maxima and minima) and the temporal variation in the leaf area index (LAI), and the fraction of photosynthetically active radiation (fPAR), are three fundamental biophysical characteristics of the plant canopy that should parameterise ecophysiological models of water use (evapotranspiration) and carbon sequestra...

Land cover change analysis was performed for three catchments in the rural Eastern Cape, South Africa, for two time steps (2000 and 2014), to characterize landscape conversion trajectories for sustained landscape health. Land cover maps were derived: (1) from existing data (2000); and (2) through object-based image analysis (2014) of Landsat 8 imag...

Future land cover changes may result in adjustments to biophysical drivers impacting on: net ecosystem carbon exchange (NEE), catchment water use through evapotranspiration (ET), and even Global Circulation Models. The Land Change Modeller (Idrisi Terrset 18.08) and land cover for 2000 and 2014 is used to predict land cover for the S50E catchment i...

Determining water and carbon fluxes over a vegetated surface is important in a context of global environmental changes and the fluxes help in understanding ecosystem functioning. Pursuant to this, the study measured evapotranspiration (ET) using an eddy covariance (EC) system installed over an intact example of the Albany Thicket (AT) vegetation in...

Evapotranspiration (ET) is one of the least understood components of the water cycle, particularly in data scarce areas. In a context of climate change, evaluating water vapour fluxes of a particular area is crucial to help understand dynamics in water balance. In data scarce areas, ET modelling becomes vital. The study modelled ET using the Penman...

Australian acacias have spread to many parts of the world. In South Africa, species such as A. mearnsii and dealbata are invasive. Consequently, more effort has focused on their clearing. In a context of increasing clearing costs, it is crucial to develop innovative ways of managing invasions. Our aim was to understand the biophysical properties of...

South Africa is facing increasing water stress, while water quality and availability issues are becoming more acute. The WRC’s meaningful contribution to the development of the capacity of the water sector and the broadening of the country’s water centred R&D base has resulted in the country being much better prepared to deal with water management...

In semi-arid, groundwater-dependent regions of South Africa, allocation of additional water resources can become problematic in the absence of quantified regional groundwater recharge values. In this study in the northern Sandveld, remote-sensing-data products for precipitation (P) and evapotranspiration (ET) are used to quantify groundwater rechar...

Remote sensing-based evapotranspiration (ET) algorithms developed in recent years are well suited for estimating evapotranspiration and its spatial trends over time. In this paper the application of energy balance methods in South Africa is reviewed, showing that the Surface Energy Balance Algorithm for Land (SEBAL) model is the most widely used, b...

Remote sensing-based evapotranspiration (ET) algorithms developed in recent years are well suited for estimating evapotranspiration and its spatial trends over time. In this paper the application of energy balance methods in South Africa is reviewed, showing that the Surface Energy Balance Algorithm for Land (SEBAL) model is the most widely used, b...

The Surface Energy Balance System (SEBS) model is a scale independent model for the estimation of evaporative fraction (EF) using satellite earth observation data. The latent heat flux is calculated as residual after the net radiation, soil and sensible heat fluxes have been obtained, and EF is estimated. EF can be upscaled to a daily actual evapot...

The overall objective of this project is to determine the usefulness and applicability of using remote sensing technologies as a tool for resource assessment towards the determination of the legal compliance of surface and groundwater use. This project focuses on the creation of new knowledge and being at the innovative edge of the topic. This stud...

The focus of this paper is on the pre-packaged version of SEBS in ILWIS and the sensitivity of SEBS to some parameters over which the user has some control when using this version of the model, in order to make informed choices to limit uncertainties. The sensitivities of SEBS to input parameters are related to daily ET rather than energy flux resu...

South Africa is a water scarce country where it is important for water managers to have accurate information on water resource occurrence and use. A remote sensing project highlighted many uncertainties in using complex remote sensing models to determine water use in a heterogeneous study area. The severity of the uncertainties was confirmed as the...

This is a report of the work on the revision of the sediment yield map of Southern Africa. The current sediment yield determination methodology of Southern Africa was developed in 1992 (Rooseboom et al., 1992). Continual revision of sediment yield prediction methods is necessary in the wake of changing environments, more data, advanced analysis too...