Lake Victoria Basin Rainfall Over the 20th Century
Kizza, M., Rodhe, A., Xu, C.-Y., Ntale, H.K. and Halldin, S. 2009. Temporal rainfall variability in the Lake Victoria Basin in East Africa during the twentieth century. Theoretical and Applied Climatology 98: 119-135.
To conduct such a study, Kizza et al. calculated trends and step changes in seasonal and annual rainfall amounts for 20 weather stations located within the Lake Victoria basin, obtaining results for four different time periods: (1) all of each station's available data, (2) 1941-1980, (3) 1961-1990, and 1971 to the end of each station's time series. In the case of trends, results were obtained using the Mann-Kendall method, while step changes were determined using the Worsley Likelihood method.
The five researchers determined that, overall, "the Lake Victoria basin experienced a predominantly positive trend over the twentieth century." More specifically, they report that "a total of 400 cases were analyzed of which 65 (17%) had significant trends," noting that "of the stations showing significant trend, 43 cases (67%) are positive trends and 22 (33%) are negative." In addition, they determined that "for stations with significant trend based on more than 60 years of recording the trend represents an increase of 2-4 mm per year," and that "this translates to a rainfall increase of about 24% over the twentieth century."
In view of the great importance of Lake Victoria to much of Africa, the results obtained by Kizza et al. must be considered very good news, which is just the opposite of what is typically predicted by the world's climate alarmists to result from "unprecedented" global warming.
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