introduction dust storms, one type of dust event, are in most cases the result of turbulent winds, including convective haboobs, which raise large quantities of dust from desert surfaces and reduce visibility to less than 1 km. this dust reaches concentrations in excess of 6000 mg m3 in severe events. the major dust source regions are areas of arid and hyper-arid, with mean annual rainfalls of ...

In order to better understand the formation mechanism of rainstorm in China and promote disaster prevention reduction, based on meteorological data National Meteorological Information Center Japan Agency, this paper draws isobaric surface map 850 hPa 500 hPa, relative humidity precipitation distribution map. study, synoptic methods were used analyze heavy process North from August 23th 24th, 20...

introduction climate change is an important environmental hazard that has been discussed in recent years. increasing the number or frequency of extreme climatic events such as severe droughts, floods, storms, heat and cold waves and heavy rains are the evidences of climate change. any of these events, due to the severity and persistence and their spread are a natural hazard that adverse effects...

The meteorological conditions during the period of spring transition over the Middle East and the Persian Gulf and adjacent land area is investigated. Monthly and seasonal variations of large-scale atmospheric patterns and wind aloft features at different levels were drawn from data collected from the National Centers for Environmental Prediction and National Center for Atmospheric Researches. ...

in this study, frequency and location of frontogenesis related to heavy rainfall have been analyzed using environmental to circulation approach. based on the threshold of upper 99 percent, we selected 125 days of the super and overall heavy rainfall from irimo data base (included 1437 synoptic, climatic and rain gage stations from 21/3/1961 up to 31/12/2004). frontogenesis frequency and their l...