Variability of Intertropical Convergence Zone (ITCZ) and Extreme Weather Events

IntroductionFor case one, the UK severed from abnormal severs cold winter season on 2009.The mean temperature for that winter was 3.2 °C, which was 0.5 °C below average of , provisionally making it the coldest winter since 1996/97.Whereas, Mean temperatures over the UK were 1.1 °C below the average during December 2008, 0.6 °C below average during January and 0.2 °C above average during February during that season.A generally cold first half to December was followed by a milder period, before turning very cold by the first of January see Figure (1).This very cold spell persisted for the first 10 days of January, with some severe frosts, followed by alternating milder and colder periods.Despite a cold (and snowy) first half of February, milder conditions later resulted in near-normal temperatures overall.Rainfall amounts over the UK were below the 1971-2000 average during December with 70%, January was close to average with 98% and February was drier than average with 63%.In December, parts of south-east England, East Anglia and Wales had less than 50% of the average rainfall and in February much of Wales, north-west England and western Scotland recorded less than 50% of average.Significant snowfalls occurred in the first half of February, particularly over England and Wales during the first week, when depths greater than 15 cm were recorded quite widely.The last time of that winter season a comparable snowy spell occurred was in February 1991 (MetOffice., UK, 2009).However, there are several scientific literatures challenge the abnormal weather conditions [e.g.(Cohen et al., 2001;Hafez 2007Hafez , 2008;;and Rosting & Kristjansson 2008)].In addition to that identification, oscillations, and influence of the ITCZ (Intertropical Convergence Zone) in the atmospheric cooling weather conditions had studied by (Bates 1970;Pike 1972; Citeau 1988b;