Seasonal Variability of Aerosol Optical Depth and Cloud Optical Depth over Kogi East, Nigeria Using MODIS Aqua Satellite Observations (2019–2025)

Authors

  • Abubakar Rasaq Centre for Atmospheric Research, Anyigba.
  • Friday Egbunu
  • Luqman Ugbede Aliyu
  • Hamza Abubakar
  • Robert Ojonugwa Okpanachi
  • Abdulrazaq Ibrahim Abubakar

DOI:

https://doi.org/10.33003/fjs-2026-1016-5702

Keywords:

Aerosol Optical Depth, Cloud Optical Depth, Kogi East, MODIS Aqua, Seasonal Variability

Abstract

Atmospheric aerosols and clouds are important components of the climate system because of their effects on radiation, precipitation, and atmospheric processes. However, limited information is available on the combined seasonal behaviour of aerosol and cloud optical properties over Kogi East, Nigeria. This study investigated the seasonal and interannual variability of Aerosol Optical Depth (AOD) and Cloud Optical Depth (COD) over Kogi East using MODIS Aqua satellite observations from January 2019 to December 2025. Monthly AOD and COD observations were obtained through the NASA Giovanni platform and analysed using descriptive statistics, seasonal comparison, Pearson correlation, and simple linear regression. AOD ranged from 0.328 to 1.368, with a mean of 0.616 ± 0.259, while COD ranged from 1.966 to 20.088, with a mean of 8.290 ± 4.591. AOD generally exhibited higher values during the dry season, consistent with enhanced dust transport and reduced precipitation, whereas COD was generally higher during the wet season, when atmospheric moisture and convective cloud development were enhanced. Pearson correlation showed a moderate negative association between AOD and COD (r = -0.469), while the regression model (COD = 13.432 − 8.3394AOD) produced an R² of 0.2202. The results indicate that AOD and COD exhibit strong seasonal variability and that their relationship is also affected by other atmospheric processes. The study provides a satellite-based baseline for further investigation of aerosol–cloud interactions over Kogi East and the wider Guinea Savannah region of Nigeria.

Author Biography

  • Abubakar Rasaq, Centre for Atmospheric Research, Anyigba.

    Senior Executive Officer,

    Centre for Atmospheric Research, Anyigba. National Space Research and Development Agency (NASRDA)

References

Andreae, M. O., & Rosenfeld, D. (2008). Aerosol-cloud-precipitation interactions. Part 1. The nature and sources of cloud-active aerosols. Earth-Science Reviews, 89(1–2), 13–41. https://doi.org/10.1016/j.earscirev.2008.03.001

Ayanlade, A., Atai, G., & Jegede, M. O. (2019). Variability in atmospheric aerosols and effects of humidity, wind and Inter-Tropical Discontinuity over different ecological zones in Nigeria. Atmospheric Environment, 201, 369–380. https://doi.org/10.1016/j.atmosenv.2018.12.039

Balarabe, M. A., & Isah, M. N. (2019). A modified linear regression model for predicting aerosol optical depth (AOD) in Ilorin-Nigeria. FUDMA Journal of Sciences, 3(1), 140–145.

Boucher, O., Randall, D., Artaxo, P., Bretherton, C., Feingold, G., Forster, P. M., Kerminen, V.-M., Kondo, Y., Liao, H., Lohmann, U., Rasch, P., Satheesh, S. K., Sherwood, S. C., Stevens, B., & Zhang, X. Y. (2013). Clouds and aerosols. In T. F. Stocker, D. Qin, G.-K. Plattner, et al. (Eds.), Climate change 2013: The physical science basis (pp. 571–657). Cambridge University Press.

Kaufman, Y. J., Tanré, D., & Boucher, O. (2002). A satellite view of aerosols in the climate system. Nature, 419(6903), 215–223. https://doi.org/10.1038/nature01091

Khan, M., Tariq, S., & Ul Haq, Z. (2024). An investigation of the ultraviolet aerosol index and Ångström exponent and their relationship with meteorological parameters over Nigeria using satellite remote sensing. Pure and Applied Geophysics, 181(8), 2651–2676. https://doi.org/10.1007/s00024-024-03545-6

Knippertz, P., & Todd, M. C. (2012). Mineral dust aerosols over the Sahara: Meteorological controls on emission and transport and implications for climate. Reviews of Geophysics, 50(1), RG1007. https://doi.org/10.1029/2011RG000362

Levy, R. C., Mattoo, S., Munchak, L. A., Remer, L. A., Sayer, A. M., Hsu, N. C., & Shi, Y. (2013). The Collection 6 MODIS aerosol products over land and ocean. Atmospheric Measurement Techniques, 6(11), 2989–3034. https://doi.org/10.5194/amt-6-2989-2013

Platnick, S., King, M. D., Meyer, K. G., Wind, G., Amarasinghe, N., Marchant, B., Arnold, G. T., & Zhang, Z. (2017). The MODIS cloud optical and microphysical products: Collection 6 updates and examples from Terra and Aqua. IEEE Transactions on Geoscience and Remote Sensing, 55(1), 502–525. https://doi.org/10.1109/TGRS.2016.2610522

Prospero, J. M., Ginoux, P., Torres, O., Nicholson, S. E., & Gill, T. E. (2002). Environmental characterization of global sources of atmospheric soil dust identified with the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) absorbing aerosol product. Reviews of Geophysics, 40(1), 1002. https://doi.org/10.1029/2000RG000095

Remer, L. A., Kaufman, Y. J., Tanré, D., Mattoo, S., Chu, D. A., Martins, J. V., Li, R.-R., Ichoku, C., Levy, R. C., Kleidman, R. G., Eck, T. F., Vermote, E., & Holben, B. N. (2005). The MODIS aerosol algorithm, products, and validation. Journal of the Atmospheric Sciences, 62(4), 947–973. https://doi.org/10.1175/JAS3385.1

Taylor, J. W., Haslett, S. L., Bower, K. N., Flynn, M. J., Crawford, I., Dorsey, J. R., Choularton, T. W., Connolly, P. J., Hahn, V., Voigt, C., Sauer, D., Dupuy, R., Brito, J., Schwarzenboeck, A., Bourrianne, T., Denjean, C., Rosenberg, P. D., Flamant, C., Lee, J. D., Vaughan, A., Hill, P. G., Brooks, B. J., Catoire, V., Knippertz, P., & Coe, H. (2019). Aerosol influences on low-level clouds in the West African monsoon. Atmospheric Chemistry and Physics, 19(13), 8503–8522. https://doi.org/10.5194/acp-19-8503-2019

Twomey, S. (1974). Pollution and the planetary albedo. Atmospheric Environment, 8(12), 1251–1256. https://doi.org/10.1016/0004-6981(74)90004-3

Twomey, S. (1977). Atmospheric aerosols. Elsevier.

Yang, L., Luo, P., Zhang, Z., Song, Y., Ren, K., Zhang, C., Awange, J. L., Atkinson, P. M., & Meng, L. (2024). A spatio-temporal unmixing with heterogeneity model for the identification of remotely sensed MODIS aerosols: Exemplified by the case of Africa. International Journal of Applied Earth Observation and Geoinformation, 132, 104068. https://doi.org/10.1016/j.jag.2024.104068

Yusuf, N., & Sa'id, R. S. (2023). Spatial distribution of aerosol burden and evaluation of changes in aerosol optical depth using multi-approach observations in a tropical region. Heliyon, 9(8), e18815. https://doi.org/10.1016/j.heliyon.2023.e18815

Monthly variation of Aerosol Optical Depth (AOD) over Kogi East, Nigeria, January 2019 to December 2025

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Published

04-09-2026

How to Cite

Abubakar Rasaq, Egbunu, F., Aliyu, L. U., Abubakar, H., Okpanachi, R. O., & Abubakar, A. I. (2026). Seasonal Variability of Aerosol Optical Depth and Cloud Optical Depth over Kogi East, Nigeria Using MODIS Aqua Satellite Observations (2019–2025). FUDMA Journal of Sciences, 10(16), 526-532. https://doi.org/10.33003/fjs-2026-1016-5702

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