Trend Analysis of Mean Annual Temperature in Sokoto Metropolis Between 1971 And 2020 Using Man-Kendall And Sen’s Slope Estimator

Abstract: Information on trends and changes in atmospheric conditions over a given region can enhance good policy making to develop strategies to curb heat waves and disaster risk management.

The time series temperature data between 1971 and 2020 (50 years) of Sokoto Metropolis was used in this study to identify the trend and slope magnitude in the series. The trend was analyzed using the Mann-Kendal non-parametric test and the Sen’s slope estimator was used to estimate the degree or rate of increase or decrease. Linear regression was employed to evaluate the linear trend in the data and coefficient of variation, CV was used to estimate the level of variability.

The decadal trend analysis shows an increasing trend as indicated by the Mann-Kendall’s tau and p-value of +0.48 and 7.8 x 10 ^-5 (<0.001) respectively. Also, the Sen’s slope estimator was positive and found to be +0.022 ^oC per year, representing the rate of increase in trend for yearly annual temperature. Furthermore, the results show that the analysis of monthly rainfall has a varied trend of temperature in the dry months. It also shows a positively increasing warming trend for the months of April, May and September while August and December show moderate warming. This study will help the government or policymakers to develop appropriate coping and mitigation strategies for the most vulnerable areas with regards to global warming and climate change.

Atmospheric conditions, Mann-Kendall (MK), Sen’s slope estimator, Decadal, Trend analysis

1. Adamu, A., and Ma’aruf, M. (2019): Climate change in Extreme Northern Nigeria: Evidence from Rainfall Trend in Sokoto State. Dutse Journal of Pure and Applied Sciences (DULOPAS), Vol 5 (2a): 18pa7-194, 2019 [Google Scholar] [Crossref]

2. Adedokun, S. A., & Alabi, M. O. (2020): Climate change awareness and perceptions of rural farming households in Nigeria. Environmental Science and Pollution Research, 27(34), 43104-43112. https://doi.org/10.1007/s11356-020-10389-8 [Google Scholar] [Crossref]

3. Adeyeri, E. O. and Adejuwon, J. O. (2021): Trends and variability of temperature and precipitation extremes in the Sokoto Rima River Basin. [Google Scholar] [Crossref]

4. Agarwal, S.; Suchithra, A. & Singh, S. P. (2021): Analysis and interpretation of rainfall trend using Mann-Kendall’s and Sen’s slope method. Indian Journal of Ecology 48 (2), 453–457. [Google Scholar] [Crossref]

5. Agbo, E. P., Ekpo, C. M. & Edet, C. O. (2021): Analysis of the effects of meteorological parameters on radio refractivity, equivalent potential temperature and field strength via Mann-Kendall test. Theoretical and Applied Climatology 143, 1437-1456. [Google Scholar] [Crossref]

6. Agidi, O. E., Eichie, J. O. and Oyedum, O. D. (2021): Trend Analysis of Temperature and Relative Humidity across the Climatic Zones of Nigeria; 3rd School of Physical Sciences Biennial International Conference, Futminna 2021 Spsbic, 559-565 [Google Scholar] [Crossref]

7. Ahmad, R. G. (2015): Changes and Trends in Maximum, Minimum and Mean Temperature Series in Iran. Atmospheric Science Letters 16 (3), 366–372. DOI: 10.1002/asl2.569. [Google Scholar] [Crossref]

8. Akinbile, C.O.; Ogunmola, O.O.; Abolude, A.T.; Akande, S.O. (2020): Trends and spatial analysis of temperature and rainfall patterns on rice yields in Nigeria. Atmos. Sci. Lett. 2020, 21, e 944. [Google Scholar] [Crossref]

9. Alhaji, U.U.; Yusuf, A.S.; Edet, C.O.; Oche, C.O.; Agbo, E.P. (2018): Trend analysis of temperature in Gombe State using Mann-Kendall trend test. J. Sci. Res. Rep. 2018, 20, 1–9. [Google Scholar] [Crossref]

10. Aswad, Fifawaz, Kh.; Yousif, Ali A. and Ibrahim, Sayran A. (2020): Trend analysis using Man-Kendall and Sen’s slope estimator for annual and monthly rainfall for Sinjar District, Iraq. Journal of University of Duhok, Vol.32, No.2 (Pure and Eng. Sciences), Pp 501-508, 3232 (Special Issue) 3rd international conference on recent innovations in engineering (ICRIE) Duhok, September 9-10-2020. [Google Scholar] [Crossref]

11. Baig, M. R. I., Naikoo, M.W., Ansari, A. H., Ahmad, S. & Rahman, A. (2021): Spatio-temporal analysis of precipitation pattern and trend using standardized precipitation index and Mann–Kendall test in coastal Andhra Pradesh. Modeling Earth Systems and Environment 8, 2733–2752. [Google Scholar] [Crossref]

12. Brunetti, M. Maugeri and T. Nanni, (2012): Change in total precipitation, rainy days and extreme the Eastern Black Region, Turkey, Journal of Water Resources and Protection, 4 (2012), 99-105. [Google Scholar] [Crossref]

13. Collins, W. J.; Bellouin, N.; Doutriaux-Boucher, M.; Gedney, N.; Halloran, P.; Hinton, T.; Hughes, J.; Jones, C.D.; Joshi, M.; Liddicoat, S., Martin, G., O’Connor, F., Rae, J., Senior, C., Sitch, S., Totterdell, I., Wiltshire, A. and Woodward, S. (2011): Development and Evaluation of an Earth-System Mode—HadGEM2. Geoscientific Model Development, 4, 1051-1075. https://doi.org/10.5194/gmd-4-1051-2011 [Google Scholar] [Crossref]

14. Deumlich, D.; Gericke, A. (2020): Frequency trend analysis of heavy rainfall days for Germany. Water 2020, 12, 1950. [Google Scholar] [Crossref]

15. Edokpa, D.O.; Ede, P.N.; Diagi, B.E.; Ajiere, S.I. (2023): Rainfall and temperature variations in a dry tropical environment of Nigeria. J. Atmos. Sci. Res. 2023, 6, 50–57. [Google Scholar] [Crossref]

16. Efeizomor, R. O. (2023): Climate Change Trends in Nigeria: An Analysis of Historical Data from 1900-2020. International Journal of Scientific Development and Research (IJSDR) 154. Volume 8 Issue 8. ISSN: 2455-2631 August 2023 IJSDR | IJSDR2308021 www.ijsdr.org. [Google Scholar] [Crossref]

17. Eris, E. and N. Agiralioglu, (2001): Homogeneity and trend analysis of hydrometeorological data of events in North – Eastern Italy, International Journal of Climatology, 21(2001), 861-871. [Google Scholar] [Crossref]

18. Fabeku, B. B. and Okogbue, E. C. (2014): Trends in vegetation Response to Drought in Sudano-Sahelian Part of Nigeria. Atmospheric and Climate Sciences, 4, 569-588. http://dx,doi,org/10.4236/acs.2014.44052 [Google Scholar] [Crossref]

19. Gadedjisso-Tossou, A., Adjegan, K. I. & Kablan, A. K. M. (2021): Rainfall and temperature trend analysis by Mann–Kendall test and significance for Rainfed Cereal Yields in Northern Togo. Science 3 (1), 17. [Google Scholar] [Crossref]

20. Geerts, B. (2002): “Empirical estimation of the monthly-mean daily temperature range,” Theoretical and Applied Climatology, vol. 73, no. 3-4, pp. 101–132, 2002. [Google Scholar] [Crossref]

21. Geerts, B. (2003: Empirical estimation of the monthly-mean daily temperature range. Theoretical and Applied Climatology, 74: 145 – 165. [Google Scholar] [Crossref]

22. Gunduz, F.; Zeybeko˘ glu, U. (2024): Analysis of temperature and precipitation series of Hirfanli Dam Basin by Mann Kendall, Spearman’s Rho and Innovative Trend Analysis. Turk. J. Eng. 2024, 8, 11–19. [Google Scholar] [Crossref]

23. Hutschinson, (1985): Rainfall analysis of the Sahellian drought in Gambia, J. Clim, 5 (1985), 665- 672. [Google Scholar] [Crossref]

24. IPCC (2001): Climate Change: The Scientific Basis, J.T. Houghton, Y. Ding, D.J. Griggs, M. Noguer, P.J. van der Linden, X. Dai, K. Maskell, and C.A. Johnson (eds.). Cambridge University Press, Cambridge, 1–881. [Google Scholar] [Crossref]

25. IPCC. (2001): Climate Change: The Scientific Basis, J.T. Houghton, Y. Ding, D.J. Griggs, M. Noguer, P.J. van der Linden, X. Dai, K. Maskell, and C.A. Johnson (eds.). Cambridge University Press, Cambridge, 1–881. [Google Scholar] [Crossref]

26. IPCC. 1990. “Climate Change: The Intergovernmental Panel on Climate Change Scientific Assessment. WMO/UNEP/IPCC, Cambridge University press, Cambridge, 200pp [Google Scholar] [Crossref]

27. Jones, P.G.; Thornton, P.K. (2003): The potential impacts of climate change on maize production in Africa and Latin America in 2055. Glob. Environ. Chang. 2003, 13, 51–59. [Google Scholar] [Crossref]

28. Karabulut, M. Gurbuz and H. Korkmaz, (2008): Precipitation and temperature trend analyses in Samsun, Int. J. Environmental Application and Science, 3(5) (2008), 399-408. [Google Scholar] [Crossref]

29. Karaburun, A. Demirci and F. Kora, (2011): Analysis of spatially distributed annual, seasonal and monthly temperatures in Istanbul from 1975 to 2006, World Applied Sciences Journal, 12(10) (2011), 1662-1675. [Google Scholar] [Crossref]

30. Kendall, M. G., 1975, “Rank correlation methods”, 4th edition, Charles Griffin, London, UK. [Google Scholar] [Crossref]

31. Mallick, J.; Talukdar, S.; Alsubih, M.; Salam, R.; Ahmed, M.; Kahla, N.B.; Shamimuzzaman, M. (2021): Analysing the trend of rainfall in Asir region of Saudi Arabia using the family of Mann-Kendall tests, innovative trend analysis, and detrended fluctuation analysis. Theor. Appl. Climatol. 2021, 143, 823–841. [Google Scholar] [Crossref]

32. Muia, V.K.; Opere, A.O.; Ndunda, E.; Amwata, D.A. (2024): Rainfall and Temperature Trend Analysis using Mann-Kendall and Sen’s Slope Estimator Test in Makueni County, Kenya. J. Mater. Environ. Sci. 2024, 15, 349–367. [Google Scholar] [Crossref]

33. N-inf-G, (2020): Sokoto State of Nigeria - Nigeria Information & Guide. www.nigeriagalleria.com. [Google Scholar] [Crossref]

34. NPC, (2006): 2006 PHC Priority Tables – National Population Commission . population.gov.ng. [Google Scholar] [Crossref]

35. Ogbue, C.P.; et al. (2024): Assessing desertification vulnerability and mitigation strategies in northern Nigeria: A comprehensive approach. Heliyon 2024, 10, e31167. [Google Scholar] [Crossref]

36. Ogunjobi, K. O., Adamu, Y., Akinsanola, A. A., and Orimoloye, I. R. (2018): Spatio-tmporal Analysis of land use dynamics and its potential indications on land surface temperature in Sokoto Metropolis, Nigeria. R. Soc. Open sci. 5:180661. http://dx.doi.org/10.1098/rsos.180661 [Google Scholar] [Crossref]

37. Okoduwa, A. K. and Amaechi, C.F. (2024): Spatial Distribution of Climate Change Variables (Rainfall and Temperature): Case Study of Delta State, Nigeria. Research Square 2024. [Google Scholar] [Crossref]

38. Olaniran, O. J., Adewole, A. T., & Ogunjobi, K. O. (2018): Temperature and precipitation extremes in the Upper Niger River-Basin, West Africa. International Journal of Climatology, 38(5), 2335-2347. [Google Scholar] [Crossref]

39. Olusegun, C. F..;Rabiu, A. B.; Ndeda, J. O. H., and Okogbue, E. O. (2014):Trends of Temperature and Signature of Solar Activity in Selected Stations in Nigeria. Atmospheric and Climate Sciences, 4, 171-178. doi: 10.4236/acs.2014.42020. [Google Scholar] [Crossref]

40. Pandey, V.; Pandey, P.K.; Chakma, B.; Ranjan, P. (2024): Influence of short-and long-term persistence on identification of rainfall temporal trends using different versions of the Mann-Kendall test in Mizoram, Northeast India. Environ. Sci. Pollut. Res. 2024, 31, 10359–10378. [Google Scholar] [Crossref]

41. Peel, M. C.; Finlayson, B. L. & McMahon, T. A. (2007): Updated world map of the Köppen–Geiger climate classification" (PDF). Hydrology and Earth System Sciences. 11 (5): 1633–1644. Bibcode:2007HESS...11.1633P. doi:10.5194/Hess-11-1633-2007. ISSN 1027-5606. [Google Scholar] [Crossref]

42. Ragatoa, D. S.; Ogunjobi, K. O.; Okhimamhe, A. A.; Francis, S. D., and Adet, L. (2018): A Trend Analysis of Temperature in Selected Stations in Nigeria Using Three Different Approaches. Open Access Library Journal 5, 1–17. DOI: 10.4236/oalib.1104371 [Google Scholar] [Crossref]

43. Ray, S.; Das, S. S.; Mishra, P. & Al Khatib, A. M. G. (2021): Time series SARIMA modelling and forecasting of monthly rainfall and temperature in the South Asian countries. Earth Systems and Environment 5, 531–546. [Google Scholar] [Crossref]

44. Rebetez, M. (2001): “Changes in daily and nightly day-to-day temperature variability during the twentieth century for two stations in Switzerland,” Theoretical and Applied Climatology, vol. 69, no. 1-2, pp. 13–21, 2001. [Google Scholar] [Crossref]

45. Statistics by Jim, (2019): https://statisticsbyjim.com/jim_frost/ [Google Scholar] [Crossref]

46. Subbaramaya, I. and O.S.R. Bhanu–Kumar, (2015): Variation of the onset of the summer monsoon in swat river basin, Pakistan. Adv. Meteorol. 2015, 2015, 431860. [Google Scholar] [Crossref]

47. Topographic sheet. (1990): Alied Surveryors, Surulere, Lagos. Sokoto, South-west, topographic sheet, No. 54, Edition 2, with scale, v. 1, 1990. p. 50- 60. [Google Scholar] [Crossref]

48. Turkes, M.; Utku, M. Sumer, and Gonul Kilic. (1992): Protection of the Atmosphere and Climate Change. State Meteorological Services: Ankara, Turkey. [Google Scholar] [Crossref]

49. Turkes, M.; Utku, M., Sumer, and Gonul Kilic. (1995):“Variations and Trends in Annual Mean Air Temperatures in Turkey with respect to Climatic Variability”. International Journal of Climatology, 15:557-564. [Google Scholar] [Crossref]

50. Turkes, M. (1999): Vulnerability of Turkey to desertification with respect to precipitation and aridity conditions, Tr. J. Engineering and Environmental Science, 23(1999), 363-380. [Google Scholar] [Crossref]

51. Turkes, T. Koc and F. Saris, (2009): Spatio–temporal variability of precipitation total series over Turkey, Int. J. Climatol., 29(8) (2009), 1056-1074. [Google Scholar] [Crossref]

52. Ustaoglu, B. (2012): Trend analysis of annual mean temperature data using Mann – Kendall rank correlation test in Catalca –Kocaeli Peninsula, North West of Turkey for the period 1970 – 2011, IBAC, 2(2012), 276-287. [Google Scholar] [Crossref]

53. Wang, F.; Shao, W.; Yu, H.; Kan, G.; He, X.; Zhang, D.; Ren, M.; Wang, G. (2020): Re-evaluation of the power of the Mann-Kendall test for detecting monotonic trends in hydrometeorological time series. Front. Earth Sci. 2020, 8, 14. [Google Scholar] [Crossref]

54. World Health Organization, WHO (2022): Ending the Neglect to Attain the Sustainable Development Goals: A Rationale for Continued Investment in Tackling Neglected Tropical Diseases 2021–2030; World Health Organization: Geneva, Switzerland, 2022. [Google Scholar] [Crossref]

55. Xu, Z.; Tang, Y.; Connor, T.; Li, D.; Li, Y., & Liu, J. (2017): Climate Variability and Trends at a National Scale. Scientific Reports 7, 3258. DOI: 10.1038/s41598-017-03297-5 [Google Scholar] [Crossref]

56. Yahaya, I. I.; Wang, Y.; Zhang, Z.; Inuwa, A.Y.; Zhao, Y.; You, Y.; Basiru, H.A.; Ochege, F.U.; Na, Z.; [Google Scholar] [Crossref]

57. Yahaya, O.M.; Ogolo, E.O.; Agele, S.O.; Olanrewaju, A.V.(2024): Monitoring Climate Extreme Events Trend in Nigeria Using Climpact2 Software. Fudma J. Sci. 2024, 8, 143–160. [Google Scholar] [Crossref]

58. Yaouba, B. & Dieudonné, B. (2022): A review of climate change and agro-industrial development in Cameroon. Environmental Protection Research 2 (1), 1– 46 [Google Scholar] [Crossref]

59. Zhihua, Z.; Rui, L.; Hui, C. Jie and Xuedi, Z. (2013): Analysis of rainfall variation over the past 55 years in Guyuan City, China, Journal of Environmental Science, Computer Science and Engineering Technology, 2(3) (2013), 640-649. [Google Scholar] [Crossref]

• Most Advanced Construction Material for Typical Boilers
• Nutrigenetic Impact of PEMT Gene Polymorphism Rs7946 On Choline Metabolism and Its Role in Personalised Nutrition
• Evaluating the Influence Factors of Media on Investor Sentiment Towards Stock Market Investments.
• To Compare the Effectiveness of Manual Traction and Mechanical Traction in Patient with Cervicogenic Headache
• Is Green Human Resource Management the Newest Trend or A Strategic Necessity?