Extreme Relativistic Electron Fluxes in GPS Orbit: Analysis of NS41 BDD-IIR Data
Nigel P. Meredith, Thomas E. Cayton, Michael D. Cayton and Richard B. Horne
Relativistic electrons in the Earth’s outer radiation belt are a significant space weather hazard. GNSS's such as the US GPS, Galileo, GLONASS, Beidou system operate in medium Earth orbit at altitudes between 19,000 and 24,000 km. They all pass through the heart of the outer radiation belt where they may be exposed to large fluxes of relativistic electrons. In this study we conduct an extreme value analysis of the daily average relativistic electron flux in GPS orbit as a function of position and energy using data from the US NS41 satellite from 10 December 2000 to 25 July 2020.... [more]

The Investment Case for Land Tenure Security in Sub-Saharan Africa: A Cost-Benefit Analysis
Frank F K Byamugisha and Nancy Dubosse
Land tenure security is a critical government service that has repercussions on agricultural productivity, housing development, business investment, and the development of urban areas. The present study presents a cost-benefit analysis of tenure security in Sub-Saharan Africa. Readers may recall that we published the first part of the study in September 2023 issue of Coordinates. The first part focussed on the cost factor and this part focusses on the benefit analysis..... [more]