Anthony Gidudu

• PhD Geomatics, MSc. Environmental Monitoring, BSc
• Associate Professor at Makerere University

Droughts are some of the most devastating natural extreme events in sub-Saharan with enormous economic impacts on agrarian economies such as Cameroon. However, knowledge and information on their dynamics and drivers in the five agroecological zones (AEZs) of Cameroon is very scanty leading to poor planning and management. Therefore, this study aime...

Over the past decade, Uganda has experienced a notable increase in extreme meteorological hazards, yet the country lacks a comprehensive disaster management strategy. Despite the critical role it plays in disaster risk reduction, there is a shortage of approaches that contribute to our understanding of social vulnerability within dynamic contextual...

This study determined the variability of wildfire susceptibility in Queen Elizabeth National Park (QENP) in space and time. QENP is a protected area in Western Uganda. MODIS and VIIRS data for a six-and-a-half-year period from January 2015-June 2021 were obtained to create an inventory of past fires. From these fires, spatial and temporal patterns...

As climate variability increases with extremes becoming more frequent, the pressure on agriculture only intensifies. A better understanding of the dynamics of direct climate drivers of agricultural productivity is therefore sought. This study aimed to analyze the long-term and recent spatiotemporal trends and associations of selected agrometeorolog...

The Universal Thermal Climate Index was used to characterize heat stress in East Africa for both past (1990-2023) and future(2030-2060) periods under two climate scenarios SSP245 and SSP585

Effective urban planning requires accurate and up-to-date spatial information. Remote sensing has contributed immensely to the efficiency of collecting this information. With remotely sensed high-spatial-resolution images, details such as buildings counted in an area can be extracted; however, traditional methods of extracting this information invo...

The rising competition for scarce land and water resources and the need to satisfy the global food demand from an ever-growing population necessitates novel methods to monitor irrigation scheme performance for improved water use efficiency. The traditional methods employed in sub-Saharan Africa to assess irrigation performance are point-based, expe...

The impact of floods on households in Uganda is becoming increasingly severe. It is often assumed that people who reside in a riverine area have adapted to flood pulses. However, in most cases, household-level risk reduction strategies are inadequate for ensuring a livelihood resilient to floods. The objective of this study was to investigate the d...

YouthMappers brings together university students coalesced around institutional chapters carrying out collaborative mapping to address humanitarian and development concerns. Beginning at three universities, in six years, YouthMappers has grown into a global movement of nearly 300 chapters in more than 60 countries. This success, in part, is attribu...

YouthMappers brings together university students coalesced around institutional chapters carrying out collaborative mapping to address humanitarian and development concerns. Beginning at three universities, in six years, YouthMappers has grown into a global movement of nearly 300 chapters in more than 60 countries. This success, in part, is attribu...

This study was conducted to map flood inundation areas along the Manafwa River, Eastern Uganda using HECRAS integrated with the SWAT model. The study mainly sought to evaluate the predictive capacity of SWAT by comparisons with streamflow observations and to derive, using HECRAS, the flood inundation maps. Changes in Land-use/cover showed by decrea...

Hyperspectral radiometric quantities were observed at a 5-minute sampling interval in the Ugandan waters of Lake Victoria during a scientific field campaign aboard research vessel (RV) IBIS from 13 to 15 October 2021. The three day fieldwork was cooridnated starting from the Napoleon Bay, Jinja, Uganda. A radiometer setup with one TriOS RAMSES-ACC...

Ground monitoring stations are widely used to monitor particulate matter (PM2.5). However, they are expensive to maintain and provide information localized to the stations, and hence are limited for large-scale use. Analysis of in situ PM2.5 shows that it varies spatially and temporally with distinct seasonal differences. This study, therefore, exp...

We report the findings from two global panel "conversations" that, stimulated by the exceptional coronavirus pandemic of 2020/21, explored the concept of resilience in geographic science teaching and learning. Characteristics of resilient teaching, both in general and with reference to GISc, are listed and shown to be essentially what might in the...

The success of disaster management efforts demands meaningful integration of data that is geographically dispersed and owned by stakeholders in various sectors. However, the difficulty in finding, accessing and reusing interoperable vocabularies to organise disaster management data creates a challenge for collaboration among stakeholders in the dis...

We detail our attempts at empirical modeling of MODIS derived Chlorophyll a (Chl a) distribution on Lake Victoria in East Africa and consequently its trophic status. This was motivated by the need for Lake Victoria specific algorithms, as the current satellite based standard algorithms overestimate derived Chl a. In situ Chl a data was hence collec...

Phenological properties are critical in understanding global environmental change patterns. This study analyzed phenological dynamics in a savannah dominated semi-arid environment of Uganda. We used moderate-resolution imaging spectroradiometer normalized difference vegetation index (MODIS NDVI) imagery. TIMESAT program was used to analyse the imag...

Phenological properties are critical in understanding global environmental change patterns. This study analyzed phenological dynamics in a savannah dominated semi-arid environment of Uganda. We used moderate-resolution imaging spectroradiometer normalized difference vegetation index (MODIS NDVI) imagery. TIMESAT program was used to analyse the imag...

Access to integrated disaster-related data through querying is still a problem due to associated semantic barriers. The disaster domain largely relies on the top-down approach of ontology development. This limits reuse due to associated commitments and complex alignments within ontologies. Therefore, there is a need to utilize a bottom-up approach...

A new height datum for Uganda is computed using the corrective surface principle. It is based on a combination of the Uganda Gravimetric Quasigeoid model (UGQ) 2014 and GNSS/levelling. UGQ2014 was derived from the Uganda Gravimetric Geoid model (UGG) 2014, which was computed from sparse terrestrial gravity data from the International Gravimetric Bu...

The water quality in Murchison Bay of Lake Victoria, the Africa’s largest fresh water lake, is on decline due to rapid urban sprawl, decrease in vegetative surface and increase in impervious surface of the drainage area resulting in eutrophication of the lake. The objectives of our study are 1) to analyze the nutrient and metal concentrations in th...

Trophic status (TS) is a water quality indicator effectively determined from Secchi Disk Depth (SDD). SDD is an in situ method of determining water clarity which is cumbersome, expensive and limited in time and space. This prompted the exploration of satellite imagery which provides a means around these challenges. Whereas algorithms for SDD retrie...

One of the grand challenges of disaster management is for stakeholders to be able to discover, access, integrate and analyze task-appropriate data together with their associated algorithms and work-flows. Even with a growing number of initiatives to publish data in the disaster management sector using open principles, integration and reuse are stil...

Information on deformation of the land surface is vital for planning of infrastructure especially in areas such as the Albertine graben with substantial amounts of oil discoveries. Traditionally, global positioning systems, precise leveling and geotechnical techniques have been used for assessing and monitoring ground deformations. While these tech...

The success of disaster risk management efforts depend on the ability of multiple stakeholders to share disaster-related information. Semantic integration of such heterogeneous information requires ontology building. The top-down-approach of ontology building has several disadvantages to knowledge representation. To support the process of ontology...

Reuse of patterns is a self-evident approach for managing interoperability concerns. Although patterns for resolving interoperability barriers exist in the literature, no study exists on adoption of interoperability patterns by Geographic Information Systems (GIS) practitioners in industry. Thus there is limited understanding of pattern re-usabilit...

Lake Victoria in East Africa is a major ecosystem, whose size and importance has warranted the exploration of MODIS imagery to provide continuous and accurate water quality information. To this effect, two sea expeditions (in November 2014 and February 2015) were carried out to collect in situ lake surface temperature (LST), chlorophyll a (Chl) and...

Listeria monocytogenes is a bacterium that is responsible for causing Listeria, a disease that has a wide range of adverse effects such as meningitis, bacteremia, complications during pregnancy, and other fatal illnesses especially among those whose immune systems are compromised. The purpose of this study was to establish hotspot candidate sites i...

Lake Victoria is one of the key ecosystems in East Africa. With a size of 68,800 km2, it is the largest lake in Africa. It supports the livelihoods of more than 20 million people directly and indirectly as a source of portable water and fish, for recreation, industrial use etc. This renders the monitoring of its water quality of paramount interest....

The Albertine region of Uganda is characterized by high levels of seismic activity and by many active normal faults. The aim of this work is to assess the potential hazard accruing from earthquakes in the Albertine region, using the probabilistic approach to assess the seismic hazard for, specifically, the Hoima and Buliisa districts. The input par...

The gravimetric quasigeoid can be determined either directly by Stokes formula or indirectly by computing the geoid first and then determining the quasigeoid-to-geoid separation which is then used to determine the quasigeoid. This paper presents the computational results of the gravimetric quasigeoid model over Uganda (UGQ2014) based on the later t...

For many developing countries such as Uganda, precise gravimetric geoid determination is hindered by the low quantity and quality of the terrestrial gravity data. With only one gravity data point per 65 km2, gravimetric geoid determination in Uganda appears an impossible task. However, recent advances in geoid modelling techniques coupled with the...

The problem faced by Geographic Information Systems (GIS) today is the lack of interoperability among the various systems. Scientists do better when they share resources: computing power, data, tools, models, protocols, and results but making resources available is not the same as making them useful to others. Thus there is need to share common und...

At 68,800 km 2 , Lake Victoria is the largest fresh water lake in Africa. It is a trans-boundary water resource supporting the livelihoods of over 20 million people directly and indirectly. It is a source of food, recreation, domestic and industry use. This has rendered its monitoring of paramount interest to several environmental agencies in Ugand...

When an earthquake occurs, seismic waves radiate away from the source and travel rapidly through the earth's crust. When these waves reach the ground surface, they cause shaking that may last from a few seconds to minutes. The nature and distribution of earthquake damage is strongly influenced by the response of soils to dynamic loading. This respo...

European initiatives for data harmonization and the establishment of remote-sensing-based services aim at the production of up-to-date land-cover information according to generally valid standards for the accurate qualification of thematic classification results. This is particularly true since new satellite systems provide data of high temporal an...

There is a global trend towards developing Spatial Data Infrastructures (SDI) for effective planning and management of transport infrastructure. In general, the components of an SDI include: data, access network, people and institutions, standards and policies. This chapter sought to investigate the nature of available spatial data in Kampala with...

This paper presents an overview of the preliminary evaluation results of the new Earth Gravitational Model (EGM08) in Uganda. The evaluation was based on a network of 12 GNSS/levelling points in Kampala and was performed in point wise (absolute) and relative (varying baselines) sense. For completeness the evaluation tests were also performed for EG...

The ability to extract accurate land cover information from satellite imagery depends on the quality of satellite data. Thus a study was made to assess the impact of topographic correction on satellite imagery where illumination effects were modelled with a DEM to quantitatively assess the classification accuracy. During the study, false colour com...

Many professionals e.g. surveyors, engineers and GIS specialists are increasingly using Glob-al Positioning System (GPS) or some other Global Navigation Satellite Systems (GNSS) for positioning and navigation. One of the greatest advantages of GPS is its ability to provide three-dimensional coordinates (latitude, longitude and height) anywhere in t...

This paper examines the use of remote sensing satellite data to predict food shortages among different categories of house-holds in famine-prone areas. Normalized Difference Vegeta-tion Index (NDVI) and rainfall estimate data, which can be derived from multi-spectral satellite radiometer images, has long been used to predict crop yields and hence f...

From the advent of the application of satellite imagery to land cover mapping, one of the growing areas of research interest has been in the area of image classification. Image classifiers are algorithms used to extract land cover information from satellite imagery. Most of the initial research has focussed on the development and application of alg...

Ensemble classification involves consulting experts in taking final decision in classification process. The idea is to improve classification accuracy when compared to their single classifier counterpart. The system is used in remote sensing imagery to obtain information about Land cover. Major challenges associated with classification accuracy inc...

Ensemble classification is an emerging area in remote sensing research whereby land cover mapping is based on a ‘consensus’ of base classifiers. It is premised on ensuring diversity among the base classifiers and predetermining the ‘consensus’ rules. Ensemble feature selection provides one of the unique ways of ensuring diversity in ensemble system...

Random ensemble feature selection is a means through which diversity in ensemble systems is imposed by randomly selecting the features (bands) that constitute the base classifiers. This paper provides insight and discusses the interplay between the size of the resulting ensembles and the consequent classification accuracy. From the results, it was...

Ensemble classification is an emerging approach to land cover mapping whereby the final classification output is a result of a consensus of classifiers. Intuitively, an ensemble system should consist of base classifiers which are diverse i.e. classifiers whose decision boundaries err differently. In this paper ensemble feature selection is used to...

Support Vector Machines (SVMs) are a relatively new supervised classification technique to the land cover mapping community. They have their roots in Statistical Learning Theory and have gained prominence because they are robust, accurate and are effective even when using a small training sample. By their nature SVMs are essentially binary classifi...

Support Vector Machines (SVMs) are a relatively new supervised classification technique to the land cover mapping community. They have their roots in Statistical Learning Theory and have gained prominence because they are robust, accurate and are effective even when using a small training sample. By their nature SVMs are essentially binary classifi...

Word processed copy. Thesis (Ph.D. (Architecture, Planning and Geomatics))--University of Cape Town, 2006. Includes bibliographical references (leaves 123-129)