The presence of clouds in the Earth’s atmosphere plays a pivotal role in regulating the Earth’s energy budget. Increased anthropogenic activities and emissions can significantly lead to changes in cloud composition and cloud structure affecting the clouds physical characteristics, hence causing alterations in the climatic conditions over Kenya. Given this, the present study examined the spatial temporal physical properties of clouds over three study sites, by paying a special consideration on cloud parameters, such as: Cloud Effective Radius (CER), Cloud Top Pressure (CTP), Cloud Top Temperature (CTT) and the Cloud Fraction (CF). These cloud parameters were retrieved from the MODerate resolution Imaging Spectroradiometer (MODIS) sensor and the Modern Era Retrospective analysis for Research and Applications, version 2 (MERRA-2) model between January 2005 and December 2020. The data retrieved on clouds physical properties was utilized to estimate the trends and spatial variations and assess their statistical significance on climate over the study domain. The Spatial patterns of seasonal mean of cloud parameters from the sensors and the model were generally characterized with positive and negative trends over Kenya observed during the four seasons. Trends in CER were found as follows: Nairobi (0.04, 0, -0.04 and -0.01) for the four seasons respectively, Malindi (0.04, 0.01, 0.04 and 0.01) and lastly Mbita (-0.06, -0.06, 0.04 and -0.05); for CTT, Nairobi, -0.1, -0.2, -0.1 and -0.2, Malindi, 0.1, -0.2, 0.1 and 0.05 and Mbita, 0.2, 0.2, -0.2 and 0.15 respectively for every season. Trends in CTP were observed to vary seasonally as follows: Nairobi -0.5, -1, 0.5 and -0.5, Malindi -0.5, -3, 1, and 0.5 and lastly Mbita 0.5, 0, -1 and -1 respectively. And finally, the spatial trends in CF observed over the four seasons over the study domains were obtained a follows: Nairobi (0.3, 0, -0.002 and 0), Malindi (0.3, 0.002, 0 and 0.001) and lastly for Mbita (0.3, 0.003, 0.001 and 0.001) respectively for the four seasons of the study. Spatial trends in the selected cloud properties were determined and observed to vary both seasonally and regionally. The study revealed patterns of trends in physical cloud properties and formed a basis for further research on clouds over Kenya.
Cite this paper
Makokha, S. N. , Makokha, J. W. and Kelonye, F. B. (2022). Long-Term Assessment of the Spatial Temporal Trends in Selected Cloud Physical Properties over the Three Distinct Sites in Kenya. Open Access Library Journal, 9, e9582. doi: http://dx.doi.org/10.4236/oalib.1109582.
Roebeling, R.A., Feijt, A.J. and Stammes, P. (2006) Cloud Property Retrievals for Climate Monitoring: Implications of Differences between Spinning Enhanced Visible and Infrared Imager (SEVIRI) on METEOSAT-8 and Advanced Very High Resolution Radiometer (AVHRR) on NOAA-17. Journal of Geophysical Research: Atmospheres, 111, 1-16. https://doi.org/10.1029/2005JD006990
Calbo, J., Pages, D. and Gonzale, J. (2005) Empirical Studies of Cloud Effects on UV Radiation: A Review. Review Geophysics, 43, 1-28.
https://doi.org/10.1029/2004RG000155
Ichoku C., Kaufman, Y.J., Remor, L.A. and Levy, R. (2004) Global Aerosol Remote Sensing from MODIS. Advances in Space Research, 34, 820-827.
https://doi.org/10.1016/j.asr.2003.07.071
George, R.C. and Wood, R. (2010) Subseasonal Variability of Low Cloud Radiative Properties over the Southeast Pacific Ocean. Atmospheric Chemistry and Physics, 10, 4047-4063. https://doi.org/10.5194/acp-10-4047-2010
Audu, M.O., Ejembi, E. and Igbawua, T. (2021) Assessment of Spatial Distribution and Temporal Trends of Precipitation and Its Extremes over Nigeria. American Journal of Climate Change, 10, 331-352. https://doi.org/10.4236/ajcc.2021.103016
Dowling, D.R. and Radke, L.F. (1990) A Summary of the Physical Properties of Cirrus Clouds. Journal of Applied Meteorology and Climatology, 29, 970-978.
https://doi.org/10.1175/1520-0450(1990)029<0970:ASOTPP>2.0.CO;2
Nyasulu, M., Haque, M.M., Boiyo, R., Kumar, K.R. and Zhang, Y.L. (2020) Seasonal Climatology and Relationship between AOD and Cloud Properties Inferred from the MODIS over Malawi, Southeast Africa. Atmospheric Pollution Research, 11, 1933-1952. https://doi.org/10.1016/j.apr.2020.07.023
Zhao, C.F., Chen, Y.Y., Li, J.M., Letu, H., Su, Y.F., Chen, T.M. and Wu, X.L. (2019) Fifteen-Year Statistical Analysis of Cloud Characteristics over China Using Terra and Aqua Moderate Resolution Imaging Spectroradiometer Observations. International Journal of Climatology, 39, 2612-2629. https://doi.org/10.1002/joc.5975
Mideva, E.M. (2021) Atrium Daylight Penetration in Dense Apartment Blocks. A Case of Roysambu Nairobi, Kenya. University of Nairobi School of the Environment Department of Architecture and Building Science, Nairobi.
Makokha, J.W., Kimani, J.N. and Angeyo, H.K. (2013) Estimation of Radiative Forcing Due to Aerosols over Selected Sites in Kenya. Journal of meteorological Research, 6, 3-13.
Boiyo, R.K., Kumar, R. and Zhao, T. (2018) Optical, Microphysical and Radiative Properties of Aerosols over a Tropical Rural Site in Kenya, East Africa: Source Identification, Modification and Aerosols Type Discrimination. Journal Atmospheric Environment, 177, 234-252. https://doi.org/10.1016/j.atmosenv.2018.01.018
Bakayoko, A., Galy-Lacaux, C., Yoboué, V., Hickman, J.E., Roux, F., Gardrat, E. and Delon, C. (2021) Dominant Contribution of Nitrogen Compounds in Precipitation Chemistry in the Lake Victoria Catchment (East Africa). Environmental Research Letters, 16, Article ID: 045013. https://doi.org/10.1088/1748-9326/abe25c
Khamala, G.W., Makokha, J.W., Boiyo, R. and Kumar, K.R. (2022) Long-Term Climatology and Spatial Trends of Absorption, Scattering, and Total Aerosol Optical Depths over East Africa during 2001-2019. Environmental Science and Pollution Research, 29, 61283-61297. https://doi.org/10.1007/s11356-022-20022-6
Boiyo, R., Kumar, K.R., Zhao, T. and Bao, Y. (2017) Climatological Analysis of Aerosol Optical Properties over East Africa Observed from Space-Borne Sensors during 2001-2015. Atmospheric Environment, 152, 298-313.
https://doi.org/10.1016/j.atmosenv.2016.12.050
Barnes, W.L., Xiong, X., Guenther, B.W. and Salomonson, V. (2003) Development, Characterization, and Performance of the EOS MODIS Sensors. Earth Observing Systems VIII, 5151, 337-345. https://doi.org/10.1117/12.504818
Mito, C.O., Boiyo, R.K. and Laneve, G. (2012) A Simple Algorithm to Estimate Sensible Heat flux from Remotely Sensed MODIS Data. International Journal of Remote Sensing, 33, 6109-6121. https://doi.org/10.1080/01431161.2012.680616
Remer, L.A., Kaufman, Y.J., Tanré, D., Mattoo, S., Chu, D.A., Martins, J.V. and Holben, B.N. (2005) The MODIS Aerosol Algorithm, Products, and Validation. Journal of the Atmospheric Sciences, 62, 947-973.
https://doi.org/10.1175/JAS3385.1
King, M.D., Platnick, S., Menzel, W.P., Ackerman, S.A. and Hubanks, P.A. (2013) Spatial and Temporal Distribution of Clouds Observed by MODIS Onboard the Terra and Aqua Satellites. IEEE Transactions on Geoscience and Remote Sensing, 51, 3826-3852. https://doi.org/10.1109/TGRS.2012.2227333
Cao, C., De Luccia, F.J., Xiong, X., Wolfe, R. and Weng, F. (2013) Early On-Orbit Performance of the Visible Infrared Imaging Radiometer Suite Onboard the Suomi National Polar-Orbiting Partnership (S-NPP) Satellite. IEEE Transactions on Geoscience and Remote Sensing, 52, 1142-1156.
https://doi.org/10.1109/TGRS.2013.2247768
Platnick, S., King, M., Ackerman, S., Menzel, W., Baum, B., Riedi, J. and Frey, R. (2003) The MODIS Cloud Products: Algorithms and Examples from Terra. IEEE Transactions on Geoscience and Remote Sensing, 41, 459-473.
https://doi.org/10.1109/TGRS.2002.808301
Platnick, S., Meyer, K.G., King, M.D., Wind, G., Amarasinghe, N., Marchant, B., Riedi, J., et al. (2016) The MODIS Cloud Optical and Microphysical Products: Collection 6 Updates and Examples from Terra and Aqua. IEEE Transactions on Geoscience and Remote Sensing, 55, 502-525.
https://doi.org/10.1109/TGRS.2016.2610522
Alam, K., Iqbal, M.J., Blaschke, T., Qureshi, S. and Khan, G. (2010) Monitoring Spatio-Temporal Variations in Aerosols and Aerosol-Cloud Interactions over Pakistan Using MODIS Data. Advances in Space Research, 46, 1162-1176.
https://doi.org/10.1016/j.asr.2010.06.025
Randles, C.A., Da Silva, A.M., Buchard, V., Colarco, P.R., Darmenov, A., Govindaraju, R. and Flynn, C.J. (2017) The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part I: System Description and Data Assimilation Evaluation. Journal of climate, 30, 6823-6850. https://doi.org/10.1175/JCLI-D-16-0609.1
Syed, A., Liu, X.P., Moniruzzaman, M., Rousta, I., Syed, W., Zhang, J. and Olafsson, H. (2021) Assessment of Climate Variability among Seasonal Trends Using in Situ Measurements: A Case Study of Punjab, Pakistan. Atmosphere, 12, Article 939.
https://doi.org/10.3390/atmos12080939
Wanjuhi, D.M. (2016) Assessment of Meteorological Drought Characteristics in North Eastern Counties of Kenya. Doctoral Dissertation, University of Nairobi, Nairobi.
Mondal, A., Kundu, S. and Mukhopadhyay, A. (2012) Rainfall Trend Analysis by Mann-Kendall Test: A Case study of North-Eastern Part of Cuttack District, Orissa. International Journal of Geology, Earth and Environmental Sciences, 2, 70-78.
Yadav, R., Tripathi, S.K., Pranuthi, G. and Dubey, S.K. (2014) Trend Analysis by Mann-Kendall Test for Precipitation and Temperature for Thirteen Districts of Uttarakhand. Journal of Agrometeorology, 16, 164-171.
https://doi.org/10.54386/jam.v16i2.1507
Ahmad, I., Tang, D., Wang, T., Wang, M. and Wagan, B. (2015) Precipitation Trends over Time Using Mann-Kendall and Spearman’s rho Tests in Swat River Basin, Pakistan. Advances in Meteorology, 2015, Article ID: 431860.
https://doi.org/10.1155/2015/431860
Saponaro, G. (2020) Application of Remotely-Sensed Cloud Properties for Climate Studies. Journal of Geophysical Research: Atmospheres, 185, 1-5.
http://hdl.handle.net/10138/308930
Lensky, I.M. and Rosenfeld, D. (2006) The Time-Space Exchangeability of Satellite Retrieved Relations between Cloud Top Temperature and Particle Effective Radius. Atmospheric Chemistry and Physics, 6, 2887-2894.
https://doi.org/10.5194/acp-6-2887-2006
Pliemon, T., Foelsche, U., Rohr, C. and Pfister, C. (2022) Subdaily Meteorological Measurements of Temperature, Direction of the Movement of the Clouds, and Cloud Cover in the Late Maunder Minimum by Louis Morin in Paris. Climate of the Past Discussions, 18, 1-39. https://doi.org/10.5194/cp-2021-179
