Trend and frequency analyses of rainfall in North west geopolitical zone of Nigeria

Nijeryanın kuzeybatı jeopolitik bölgesinde yaşayan insanların büyük çoğunluğu yağış miktarı ve diğerfaktörlere bağlı olarak tarımla iştigal ederler. İklim değişikliğinin dünya çapında yağıştaki miktar değişimine katkısağladığı bilinmektedir. Bu çalışmada mevcut olan yağış frekans ve eğilim analizlerinde Pearson log tip III dağılımıhem de Mann-Kendall ve Senin eğim teknikleri kullanılarak yıllık yağış miktarlarının toplamlarına dikkatleNileryanın kuzeybatı jeopolitik bölgesindeki yağışlar üzerine odaklanılmıştır. 1905-2008 yılları arasındaki yağışbilgileri bölgedeki beş yerden toplanmış ve literatürde verilen standart metotlarla test edilmiştir. Çalışma, bölgedekiyağışlarda eğilimler olduğu, bu eğilimlerin Senin testlerine göre % 99 oranında önemli seviyeye sahip olduğunuortaya çıkarmıştır. Senin eğimleri tüm yerleşim yerlerinde son 30 yılda aşağı doğru eğilimlerin var olduğunu açığaçıkarmıştır. Eğimler Sokoto, Kano, Kebbi, Kaduna ve Katsina için sırasıyla -0.94, -6.91; -0.94; -0.84 ve -5.66 mm/ yıl şeklindedir. Yağış frekans analizi bu yerleşim yerlerinde 2 yıllık geriye dönük periyotlar için 651.08 mm; 844.42mm 735.68 mm, 1168.47 mm ve 669.52 mm (Sokoto, Kano, Kebbi, Kaduna ve Katsina) sırasıyla ölçülmüştür. Tümyerleşim birimlerinde son 30 yılda yağışta azalma eğilimi olduğu tespit edilmiştir.

Nijerya nın Kuzeybatı jeopolitik bölgesine düşen yağış miktarlarının eğilim ve frekans analizi

The major occupation of people in the North-west geopolitical zone of Nigeria is farming, whichdepends on rainfall and other factors. It is well known that climate change has been contributing to change inamount of rainfall worldwide. In this paper the existence of trend and rainfall frequency analyses were conductedon rainfall data in North-west geopolitical zone of Nigeria with a particular attention to yearly total rainfalls usingMann- Kendall and Sen s slope techniques as well as Pearson log type III distribution. Rainfall data from 1905 2008 were collected from fve locations in the region and the test were conducted using standard methods stated inliterature. The study revealed that there are trends in the rainfall in the region and Sen s test revealed that the trendsare signifcant at 99 % confdence level. Sen s slopes revealed that there are downward trends in the rainfall for thelast 30 years in all the fve locations. The slopes are -0.94, -6.91; -0.94; -0.84 and -5.66 mm/year for Sokoto, Kano,Kebbi, Kaduna and Katsina respectively. Rainfall frequency analyses for 2 years return period for these locations(Sokoto, Kano, Kebbi, Kaduna and Katsina) are 651.08 mm; 844.42 mm 735.68 mm, 1168.47 mm and 669.52 mmrespectively. It was concluded that there are downward trends in the rainfall in last 3 decades for all the locations.

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Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi-Cover
  • ISSN: 2146-0574
  • Yayın Aralığı: Yılda 4 Sayı
  • Başlangıç: 2011
  • Yayıncı: -