Seasonal AOD analysis based on AERONET observations in North and West Africa over 2010–2019 C. M. Anoruo, Newton R. Matandirotya Discover Environment, 2025 The use of aerosol optical depth (AOD) properties Version 3 (level 2) of the surface-based AERONET was used to characterize aerosols at Eurafrican stations during the last decade of 2010–2019. The quality-assured AOD and Angstrom exponent (AE) data from Cairo_EMA_2 (30.081 N, 31.290E) and Tamanrasset_INM (22.790 N, 5.530E) are used to classify aerosols. Two additional stations from the west IER Cinzana (13.3 N, 5.9 W) and Cape Verde (16.7 N, 22.9 W) were compared as control to see the regional aerosols typing. The analyzed AOD data were first detrend to remove seasonal trend from the data and may provide difficulty in comparing relative AOD changes. Therefore, validated AOD and AE were employed to characterize the AOD type and determine the seasonal predominance. This method of analysis was derived by the deviation of the monthwise mean from the AOD data. The dominant aerosol types are coarsely absorbed due to dust from the Sahara. Saharan dust was observed in Tamanrasset_INM with AOD < 1 and AE < 1 and in Cairo_EMA_2 with AOD < 1 and AE < 1 over the spectral decadal trend. The west stations showed both AOD and AE > 1 for IER Cinzana and Cape Verde. The winter mean and standard deviation are − 0.18 ± 0.14 with AOD (− 0.009 ± 0.06) for the east. This indicates that the AOD dominance varies with the site and is heavily dependent on meteorological cycles. In the premonsoon season, the AE had AOD characteristics of 0.13 ± 0.15 (− 0.003 ± 0.03). The seasonal cycle indicates pure AOD characteristics, and the results have good confidence that the monsoon season is the major dust-driven season. The results of the study present aerosol characterization over Eurafrican stations and provide better insight into regional climate and local air pollution.
Midnight Simultaneous Observations of Spread-F and Multiple F-Layer Stratifications During the 11–12 May 2024 Geomagnetic Superstorm P. R. Fagundes, V. G. Pillat, C. M. Anoruo, G. A. S. Picanço, M. Pezzopane, J. B. Habarulema, K. Venkatesh, A. Tardelli, A. L. Christovam, F. Vieira Journal of Geophysical Research Space Physics, 2025 A geomagnetic superstorm occurred from May 10 to 12, 2024, producing significant spatial and temporal disturbances in the ionosphere. Ground‐based ionosonde and GPS‐TEC data enabled the identification, analysis, and possible interpretation of a unique event: the simultaneous occurrence of Spread‐F and multiple F‐layer stratifications during the local midnight hours of May 11. To the best of our knowledge, this is the first documented case of such a phenomenon occurring at local midnight. This study provides new insights into the dynamics of the equatorial and low‐latitude ionosphere under extreme geomagnetic conditions and highlights the critical role of coordinated, multi‐instrument observations in advancing our understanding of ionospheric electrodynamics.
Westward PPEF Plays Important Role in the Suppression of Post-Midnight Plasma Irregularities: A Case Study of the November 2021 Geomagnetic Storm Nadia Imtiaz, Teshome Dugassa, Andres Calabia, Chukwuma Anoruo, Anton Kashcheyev Journal of Geophysical Research Space Physics, 2024 We use multiple instruments data to investigate the behavior of the equatorial and low‐latitude ionosphere during the geomagnetically active and quiet period of November 1–6, 2021. In this context, total electron content (TEC) data obtained from the Global Positioning System (GPS) receivers in the equatorial and low‐latitude regions of Asia, Africa, and America are used to assess variations in plasma density during the storm. The storm‐time ionization levels were found to vary significantly in the crests of the Equatorial Ionization Anomaly (EIA) region over the 3 longitudes. The Rate of Change TEC Index (ROTI) derived from GPS receiver measurements, is used to study the equatorial/low‐latitude ionospheric plasma irregularities at various longitudes under geomagnetically quiet and disturbed conditions. Observations showed longitudinal variations in the ionospheric irregularities under both quiet and disturbed conditions. Some days exhibit a decrease in the strength of the midnight plasma irregularities toward the East, that is, the irregularities are more pronounced in West America, less common in East America, and almost non‐existent in Africa and Asia. Our investigations show this storm prevented the occurrence of plasma irregularities at the equatorial/low‐latitude region in the American sector during the night following the main phase. In general, no significant storm effects were observed at the target locations in Africa and Asia. The existence of westward Prompt Penetration Electric Field (PPEF) and the Equatorial Electrojet (EEJ) during the main phase, from midnight to noon, is clearly related with the constriction of plasma diffusion and the consequent suppression of plasma irregularities. Thus, the longitudinal dependence for the generation of midnight plasma irregularities during this storm is mainly influenced by local time occurrence of maximum ring current, and the ionospheric electric fields.
Engagement of early career researchers in collaborative assessments of IPCC reports: achievements and insights Marta Moreno-Ibáñez, Mathieu Casado, Gwenaëlle Gremion, Valentina Rabanal, Onema Adojoh, Chukwuma Anoruo, Adnan Arshad, Faten Attig Bahar, Cinthya Bello, Helena Bergstedt, Jilda Alicia Caccavo, Nicolas Champollion, Emily S. Choy, María Fernanda De Los Ríos, Henrieka Detlef, Rahul Dey, Gamil Gamal, Hugo R. Guímaro, Susana Hancock, Christel Hansen, Vincent Hare, Juan Höfer, Thajudeen Jabir, Shipra Jain, Shridhar Jawak, Mikhail Latonin, Joseph Martin, Jhon Fredy Mojica, Ryan O’Hara, Olumide Onafeso, R. Arun Prasath, Eduardo Queiroz Alves, Sergio Raez-Villanueva, Paul Rosenbaum, Sebastián Ruiz-Pereira, Valentina Savaglia, Maud van Soest, Deniz Vural Frontiers in Climate, 2024 The participation of a diverse –in terms of geography, discipline and gender– group of Early Career Researchers (ECRs) in the peer review process can help alleviate the workload of senior researchers and counteract the perceptual biases that the latter tend to show. Moreover, ECRs can benefit from developing skills that are often not included in educational programs. From 2018 to 2021, the Association of Polar Early Career Scientists, in collaboration with other associations, organized six group reviews of the Intergovernmental Panel on Climate Change (IPCC) reports by a total of more than 600 ECRs from over 70 different countries. This study aims to evaluate this group review in terms of its contribution to the production of scientific knowledge, and as a career development opportunity for ECRs. The data analyzed consists of application forms, review comments, and feedback surveys that were collected during each review process. The results of this study show that, overall, the group reviews were a success in terms of the experience of ECRs and their contribution to the peer review of the IPCC reports. Most survey respondents considered the general organization of the group reviews satisfactory and expressed interest in participating in future group reviews. However, most participants did not engage in discussions with their peers, which constitutes a missed opportunity to engage in active learning and the shared production of knowledge. ECRs made a significant contribution to the review of the IPCC reports by producing an average of 2,422 ± 532 comments per group review, 36% of which were substantive. PhD students were shown to be as proficient reviewers as postdoctoral researchers and faculty reviewers. More importantly, the diversity of reviewers in terms of geography and discipline, together with the fact that they are ECRs, can help produce more balanced scientific reports since they bring new perspectives, thus counteracting the biases that senior researchers have. These group reviews could be improved by providing more comprehensive training and facilitating communication among reviewers so that they can engage in meaningful exchanges. We conclude that the IPCC should formalize the inclusion of ECRs in future reviews of the IPCC reports.
Total Electron Content Variability in the African Ionosphere Observed during Ascending and Decaying Geomagnetic Storms Chukwuma Moses Anoruo, Francisca Nneka Okeke, Kingsley Chukwudi Okpala Geomagnetism and Aeronomy, 2023 The geomagnetic storms of October 1, 2012, and May 28, 2017, of the mid- and equatorial-latitude ionosphere responses of the African sector at cycle 24 solar ascending and descending levels are presented. The relative total electron content (rTEC) anomalies at the initial commencement until recovery phases of storms present interesting results. We employed a 15-day sliding average window to study rTEC using 7 (Global Navigation Satellite Systems) GNSS stations from the Africa Geodetic Reference Frame (AFREF) to characterize both storm ionospheric phases over the sector. The recovery phase of both storms lasted 17 h for October 1 and 14 h for May 28 with IMF Bz < 0 when the solar plasma wind speed recorded values of 353 km/s and 336 km/s, respectively. The results showed a significant equatorial latitude response of the ionosphere during both the main and recovery phases of storms that occurred at different solar activity cycles, where prestorm TEC changes occurred during the daytime. Again, positive storms observed during the prestorm events place less emphasis on the solar activity cycle mostly observed at the equatorial latitude. In addition, the magnetic field lines are shaped by the injection of a prompt penetration electric field (PPEF) that prompts prestorm rTEC enhancements, where the phenomenon of the equatorial ionization anomaly (EIA) governs the midlatitude Africa ionospheric plasma distribution based on gradients and is more pronounced in the poststorm effect.
An assessment of aerosol optical depth over three AERONET sites in South Africa during the year 2020 Newton R. Matandirotya, C.M. Anoruo Scientific African, 2023 It is important to notice that the world health organization (WHO) on the 11th of March 2020, declared COVID-19 a global pandemic and in response governments around the world introduced lockdowns that restricted human and traffic movements including South Africa. This pandemic resulted in a total lockdown from 26 March until 16 April 2020 in South Africa with expected decrease in atmospheric aerosols. In this present study, the aerosol optical depth (AOD) over Southern Africa based on ground-based remotely sensed data derived from three AERONET sites (Durban, Skukuza and Upington) during 2020 were used to detrermine the restriction resopnse on atmospheric aerosol pollution The study used data from 2019, 2018 and 2017 as base years. The AERONET derived data was complemented with the HYSPLIT Model and NCEP/NCAR Reanalysis data. The study findings show that peak increase of AOD corresponds to Angstrom exponent (AE) enhancement for two sites Durban and Skukuza during winter (JJA) while the Upington site showed a different trend where peak AOD were observed in spring (SON). The study also observed the influence of long transport airmasses particularly those originating from the Atlantic and Indian ocean moreso for the Durban and Skukuza sites (summer and autumn) thus these sites received fresh marine aerosols however this was not the case for Upington which fell under the influence of short-range inland airmasses and was likely to receive anthropogenic and dust aerosols. The major results suggest that the lockdowns did not translate into a significant decrease in AOD levels compared to previous immediate years. The results has presented restriction response of AOD over South Africa but additional analysis is required using more locations to compare results.
Influence of solar activities on climate change Environmental Engineering and Management Journal, 2020
RECENT SCHOLAR PUBLICATIONS
Ionospheric Responses in the Low-Latitude Region of Africa during the Geomagnetic Storm of 27 August 2021 CM Anoruo, FN Okeke Geomagnetism and Aeronomy 65 (7), 159-173 , 2025 2025
Midnight simultaneous observations of spread‐F and multiple F‐layer stratifications during the 11–12 May 2024 geomagnetic superstorm PR Fagundes, VG Pillat, CM Anoruo, GAS Picanço, M Pezzopane, ... Journal of Geophysical Research: Space Physics 130 (11), e2025JA034222 , 2025 2025 Citations: 1
Simultaneous occurrence of midlatitude plasma bubbles and LSTIDs during the 10 October 2024 geomagnetic storm GAS Picanço, PR Fagundes, J Moro, PAB Nogueira, M Muella, ... Advances in Space Research , 2025 2025 Citations: 2
Seasonal AOD analysis based on AERONET observations in North and West Africa over 2010–2019 CM Anoruo, NR Matandirotya Discover Environment 3 (1), 104 , 2025 2025 Citations: 1
SOLAR FLARE EFFECTS ON GEOMAGNETIC FIELDS IN THE MID AND LOW ALTITUDES. OM Ogundeji, CM Anoruo Environmental Engineering & Management Journal (EEMJ) 24 (3) , 2025 2025
Equatorial Ionization anomaly disturbances (EIA) triggered by the May 2024 solar Coronal Mass Ejection (CME): The strongest geomagnetic superstorm in the last two decades PR Fagundes, VG Pillat, JB Habarulema, M Muella, K Venkatesh, ... Advances in Space Research , 2025 2025 Citations: 12
Ionospheric Plasma Irregularities During Intense geomagnetic storms of Solar Cycle 25 N Imtiaz, A Calabia, C Anoruo, A Zahid, C Amory, B Adhikari Annales Geophysicae , 2025 2025 Citations: 2
Projected near-future changes in precipitation extremes over Anambra-Imo River Basin inferred from CMIP6 HighResMIP CC Ibe, VN Dike, SK Ishaya, JI Magaji, AA Ibe, CM Anoruo Discover Atmosphere 2 (1), 8 , 2024 2024 Citations: 1
Engagement of early career researchers in collaborative assessments of IPCC reports: achievements and insights M Moreno-Ibáñez, M Casado, G Gremion, V Rabanal, O Adojoh, ... Frontiers in Climate 6, 1395040 , 2024 2024 Citations: 8
Westward PPEF plays important role in the suppression of post‐midnight plasma irregularities: A case study of the November 2021 geomagnetic storm N Imtiaz, T Dugassa, A Calabia, C Anoruo, A Kashcheyev Journal of Geophysical Research: Space Physics 129 (6), e2023JA032367 , 2024 2024 Citations: 10
Total Electron Content Variability in the African Ionosphere Observed during Ascending and Decaying Geomagnetic Storms CM Anoruo, FN Okeke, KC Okpala Geomagnetism and Aeronomy 63 (6), 839-853 , 2023 2023
Validation of aerosol optical depth and characterization CM Anoruo Scholarly Community Encyclopedia. https://encyclopedia.pub/entry/47079 , 2023 2023
The Influence of Fine-Mode Aerosols on MODIS–AERONET Aerosol Optical Depth Disparities in the Sahel West Africa OK Nwofor, AA Uroh, C Anoruo Aerosol Science and Engineering 7 (2), 251-260 , 2023 2023
Modeling and spatial characterization of aerosols at Middle East AERONET stations CM Anoruo, SNH Bukhari, OK Nwofor Theoretical and Applied Climatology 152 (1), 617-625 , 2023 2023 Citations: 14
PhD in a Pandemic CM Anoruo International Association of Physics Students (IAPS journal) https://iaps … , 2023 2023
An assessment of aerosol optical depth over three AERONET sites in South Africa during the year 2020 NR Matandirotya, CM Anoruo Scientific African 19, e01446 , 2023 2023 Citations: 10
Aerosol load-cloud cover correlation: a potential clue for the investigation of aerosol indirect impact on climate of europe and africa CM Anoruo, OC Ibe, KN Ndubuisi Aerosol Science and Engineering 7 (1), 23-35 , 2023 2023 Citations: 3
Variations of aerosol optical depth over the West Africa sahel region CM Anoruo International Journal of Environmental Science and Technology 20 (2), 1997-2008 , 2023 2023 Citations: 5
Environmental Monitoring and Assessment of Africa Regional Air Temperature Trend CM Anoruo Economics and Policy of Energy and Environmental Sustainability, 245-255 , 2022 2022
Low latitude ionosphere responses to solar wind forcing from GNSS data in March 2001 CM Anoruo, FN Okeke, KC Okpala, A Calabia Intercontinental Geoinformation Days 4, 303-305 , 2022 2022
MOST CITED SCHOLAR PUBLICATIONS
Review of meteorological drought in Africa: historical trends, impacts, mitigation measures, and prospects B Ayugi, EO Eresanya, AO Onyango, FK Ogou, EC Okoro, CO Okoye, ... Pure and applied geophysics 179 (4), 1365 , 2022 2022 Citations: 195
Low-latitude ionospheric responses and coupling to the February 2014 multiphase geomagnetic storm from GNSS, magnetometers, and space weather data A Calabia, C Anoruo, M Shah, C Amory-Mazaudier, Y Yasyukevich, ... Atmosphere 13 (4), 518 , 2022 2022 Citations: 21
Modeling and spatial characterization of aerosols at Middle East AERONET stations CM Anoruo, SNH Bukhari, OK Nwofor Theoretical and Applied Climatology 152 (1), 617-625 , 2023 2023 Citations: 14
Equatorial Ionization anomaly disturbances (EIA) triggered by the May 2024 solar Coronal Mass Ejection (CME): The strongest geomagnetic superstorm in the last two decades PR Fagundes, VG Pillat, JB Habarulema, M Muella, K Venkatesh, ... Advances in Space Research , 2025 2025 Citations: 12
Validation of OMI seasonal and spatio-temporal variations in aerosol-cloud interactions over Banizoumbou using AERONET data CM Anoruo Journal of Atmospheric and Solar-Terrestrial Physics 211, 105457 , 2020 2020 Citations: 12
Westward PPEF plays important role in the suppression of post‐midnight plasma irregularities: A case study of the November 2021 geomagnetic storm N Imtiaz, T Dugassa, A Calabia, C Anoruo, A Kashcheyev Journal of Geophysical Research: Space Physics 129 (6), e2023JA032367 , 2024 2024 Citations: 10
An assessment of aerosol optical depth over three AERONET sites in South Africa during the year 2020 NR Matandirotya, CM Anoruo Scientific African 19, e01446 , 2023 2023 Citations: 10
Irregularities in the African ionosphere associated with total electron content anomalies observed during high solar activity levels CM Anoruo, B Rabiu, D Okoh, FN Okeke, KC Okpala Frontiers in Astronomy and Space Sciences 9, 947473 , 2022 2022 Citations: 10
Sub-seasonal aerosol characterization at the Middle East regions of AERONET site CM Anoruo Urban Climate 37, 100827 , 2021 2021 Citations: 10
Space and ground-based remote sensing comparison of seasonal interaction of aerosol-cloud-precipitable water CM Anoruo Atmospheric Environment 243, 117864 , 2020 2020 Citations: 10
Engagement of early career researchers in collaborative assessments of IPCC reports: achievements and insights M Moreno-Ibáñez, M Casado, G Gremion, V Rabanal, O Adojoh, ... Frontiers in Climate 6, 1395040 , 2024 2024 Citations: 8
Monsoon-seasonal validation of MODIS aerosol optical depth and characterization using AERONET observation retrieve over Italy CM Anoruo Environmental research 204, 111985 , 2022 2022 Citations: 7
Variations of aerosol optical depth over the West Africa sahel region CM Anoruo International Journal of Environmental Science and Technology 20 (2), 1997-2008 , 2023 2023 Citations: 5
Relationship between variation of total ozone concentration and severe geomagnetic storms over Lagos in Nigeria EC Okoro, DI Okoh, FN Okeke, CM Anoruo British Journal of Earth Sciences Research 10 (2), 39-54 , 2022 2022 Citations: 5
Modelling and Analysis of Aerosol and Cloud‑Precipitable Water Inter‑Hemispheric Interactions of Aerosol‑Satellite Data Using Ground Observation CM Anoruo Aerosol Science and Engineering , 2020 2020 Citations: 5
Aerosol load-cloud cover correlation: a potential clue for the investigation of aerosol indirect impact on climate of europe and africa CM Anoruo, OC Ibe, KN Ndubuisi Aerosol Science and Engineering 7 (1), 23-35 , 2023 2023 Citations: 3
INFLUENCE OF SOLAR ACTIVITIES ON CLIMATE CHANGE. CM Anoruo, FN Okeke Environmental Engineering & Management Journal (EEMJ) 19 (8) , 2020 2020 Citations: 3
Simultaneous occurrence of midlatitude plasma bubbles and LSTIDs during the 10 October 2024 geomagnetic storm GAS Picanço, PR Fagundes, J Moro, PAB Nogueira, M Muella, ... Advances in Space Research , 2025 2025 Citations: 2
Ionospheric Plasma Irregularities During Intense geomagnetic storms of Solar Cycle 25 N Imtiaz, A Calabia, C Anoruo, A Zahid, C Amory, B Adhikari Annales Geophysicae , 2025 2025 Citations: 2
Midnight simultaneous observations of spread‐F and multiple F‐layer stratifications during the 11–12 May 2024 geomagnetic superstorm PR Fagundes, VG Pillat, CM Anoruo, GAS Picanço, M Pezzopane, ... Journal of Geophysical Research: Space Physics 130 (11), e2025JA034222 , 2025 2025 Citations: 1
