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Subject: search.filters.subject.West Africa

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    Assessing Wildfire Occurrence in West Africa with Atmospheric Co₂ Removal
    (2025-06) Uzoma E.K.; Otunla T. A.; Nymphas E. F.; Ogunsola O. E.; Adeniyi M. O.
    The increase in wildfire occurrence is one of the consequences of the recent global temperature rise. Understanding wildfire occurrence in West Africa under atmospheric carbon dioxide removal is significant because of its implications on climate systems, ecosystems, agriculture, and socioeconomic development. This study projected the impacts of atmospheric carbon dioxide removal on fire occurrence in West Africa by analyzing the CNRM ESM1 C1 model output for the Carbon Dioxide Removal Model Inter-comparison Project (CDRMIP). Four climatological periods–1990–2019 (reference period), 2040 – 2069, 2070–2099 and 2100-2129 were analyzed using four fire indices. The periods 2040–2069, 2070–2099, and 2100–2129 have 42%, 45.9%, and 49.4% of “No Fire” category among other categories, respectively, with the Lebanese Index. With Mark 4 Grassland Fire Danger Index, a low category of fire risk is also predominant at 95.6%, 96.4%, and 66.1% for 2040–2069, 2070–2099, and 2100–2129, respectively. None of the indices projected a case of high, very high, or extreme risk in any period. “Low risk” category is predominant with all indices, particularly in Cote D’Ivoire, Ghana, Burkina Faso, Togo, Benin, and Nigeria. The low-risk category for fire occurrence during carbon dioxide removal in West Africa suggests a favorable outcome for the region’s ecosystems, agriculture, and communities. The study highlights the potential benefits of CDR beyond carbon removal, such as enhanced resilience, sustained productivity, and reduced vulnerability to climate-induced hazards like wildfires.
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    Variability of the critical frequency of the f2 layer, fof2 in west africa using ionosonde stations at ouagadougou and dakar
    (2012) Salami, O.R.; Nymphas, E.F.
    The critical frequency of the F2 layer of the ionosphere, foF2 is responsible for various effects on radio communication such as refraction, scintillation, absorption, error in Global Positioning System (GPS), jitter and phase delay. The variations of the critical frequency of the F2 layer at two different locations over West Africa were studied using ionosonde data for a solar cycle (1979 to 1989) at low, moderate and high solar activity, 1986, 1983 and 1989, respectively. The ionosonde stations are Dakar in Senegal (15°N, 17°W) and Ouagadougou in Burkina Faso (12°N, 1,8°W). The investigation of critical frequency of the F2 layer, foF2 using Relative Standard Deviation (RSD) revealed the spread and the occurrence of foF2. The results obtained in this study are proposed as equatorial input values for the development of a Variability Model for the International Reference Ionosphere.