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The tenth IMSC, Beijing, China, 2007 - International Meetings on ...

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stati<strong>on</strong>s in Iran. <str<strong>on</strong>g>The</str<strong>on</strong>g> amount of seas<strong>on</strong>al, annual ETo and rainfall trend were determined by<br />

Mann–Kendall test analysis during 1953s–2003. <str<strong>on</strong>g>The</str<strong>on</strong>g> data was then subjected to statistical<br />

tests to determine the probability distributi<strong>on</strong>s that best fit them. Suitable probability<br />

distributi<strong>on</strong>s were selected from am<strong>on</strong>g the Normal, Log-Normal, Gumbel Extreme Value Type<br />

I, Gamma and Logistic distributi<strong>on</strong>s. Seas<strong>on</strong>al and annual rainfall and ETo at 80, 50 and 30<br />

percent probability levels were determined. <str<strong>on</strong>g>The</str<strong>on</strong>g> results showed that there is not any significant<br />

trend for seas<strong>on</strong>al and annual rainfall and evapotranspirati<strong>on</strong> in all of stati<strong>on</strong>. And so, <str<strong>on</strong>g>The</str<strong>on</strong>g><br />

probability analysis of data shows that variability of evapotranspirati<strong>on</strong> and rainfall are so much,<br />

therefore determining return period of this data are useful for rainfed irrigati<strong>on</strong>. <str<strong>on</strong>g>The</str<strong>on</strong>g> results of<br />

this analysis can be attributed to expansi<strong>on</strong> of irrigati<strong>on</strong> areas and agricultural management.<br />

Keywords: climate change, rainfall, Reference crop evapotranspirati<strong>on</strong>, probability analysis,<br />

trend<br />

Error Detecti<strong>on</strong> and Checking of Inhomogenities Basing <strong>on</strong> the Metadata in Uganda<br />

Climatological Dataset<br />

Lubega N.Fortunata<br />

Department Meteorology Uganda<br />

lubegf@yahoo.com<br />

Majugu Absein<br />

Department Meteorology Uganda<br />

Climate data is a key aspect of statistical climatology, more so, today, when climate<br />

change amplitude is super imposed <strong>on</strong> climate variability, there is a dire need of well managed<br />

quality data to prove that climate change is not a myth but a reality. WMO together with the<br />

climate scientist are keen to see that artificial deviati<strong>on</strong>s within the climate data must be dealt<br />

with, hence the need for data homogenizati<strong>on</strong>. In his opening speech, at the FOUTH<br />

SEMINAR ON HOMOGENISATION AND QUALITY CONTROL IN CLIMATOLOGICAL<br />

DATABASES (Budapest Hungary WMO_TD No.1236 2004), Yadowsun Boodhoo observed<br />

that, homogenizati<strong>on</strong> of the climate data is not within the reach of all member countries. In this<br />

regard, this paper seeks to address issues pertaining to uncertainties within the climate<br />

datasets which was written out of the quality c<strong>on</strong>trol work d<strong>on</strong>e during the HYDROCLIMATIC<br />

STUDY(2003) in Uganda. <str<strong>on</strong>g>The</str<strong>on</strong>g> detecti<strong>on</strong> of errors in climatological data sets, the checking of<br />

inhomogenities basing <strong>on</strong> metadata and design of quality c<strong>on</strong>trol measures were undertaken<br />

during an inter-disciplinary study carried out by Uganda Meteorological Department (UMD) in<br />

collaborati<strong>on</strong> with the Water Resource Management Department (WRMD). <str<strong>on</strong>g>The</str<strong>on</strong>g>re were 597<br />

rainfall and 50 temperature stati<strong>on</strong>s which were digitized using CLICOM software that<br />

generated 16,363 and 1,500 records of rainfall and temperatures respectively, spanning the<br />

years 1902 to 2003.Different types of errors and their relati<strong>on</strong>ship were identified. Checking<br />

logics (nature of checking algorithm) were employed both by automatic computer programs<br />

and manual checks. <str<strong>on</strong>g>The</str<strong>on</strong>g> check tests used varied in accordance with the characteristic of<br />

logical operati<strong>on</strong>s, the element and the type of data being checked, daily, m<strong>on</strong>thly or annual<br />

113

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