weather circulation patterns play a main role in the occurrence of environmental phenomena especially in middle latitude. occurrence of dry and wet spells is in relation to synoptical system repetitions and types of weather. in this research first by using of standard precipitation index (spi), extensive droughts in the province were identified. then by using principal component analysis (pca) ...

[1] We use the GEOS-Chem chemical transport model to interpret observations of tropospheric ozone from the Tropospheric Emission Spectrometer (TES) satellite instrument in summer 2005. Observations from TES reveal elevated ozone in the middle troposphere (500–400 hPa) across North Africa and the Middle East. Observed ozone abundances in the middle troposphere are at a maximum in summer and a mi...

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...

Monthly humidity (represented as dew point temperature, DWPT) data from 22 land and 5 island Australian upper-air sites were analysed, with trends estimated over the 1965–2017 period at four pressure levels. Humidity selected to ensure that collected under consistent sampling conditions used (‘modified data’). The quality control process involved examining station metadata applying an objective...

The occurrence of major avalanche episodes in the Eastern Pyrenees (NE Spain) is estimated by means of the Poisson and the negative binomial distributions, assuming that they are rare events. The differences observed in their spatial distribution along the seven regions in which Eastern Pyrenees have been divided, suggests us to look for spatial variations in the relationship between extreme av...

Within the present study we shed light on the question whether objective circulation patterns (CP) classified from either the 500 HPa or the 700 HPa level may serve as predictors to explain the spatio-temporal variability of monsoon rainfall in the Anas catchment in North West India. To this end we employ a fuzzy ruled based classification approach in combination with a novel objective function...

By using the daily average wind speed and precipitation data of 125 stations in Jiangsu Anhui Provinces China from 1961 to 2020 monthly NCEP/NCAR reanalysis data, interannual variation characteristics its possible reasons spring compound extreme events Jiangsu–Anhui region were discussed. Results show that generally present a lesser distribution south more north. The occurring (north) 32° N are...