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Shahraiyni H.T.,Free University of Berlin | Shahraiyni H.T.,Shahrood University | Shahsavani D.,Shahrood University | Sargazi S.,Tarbiat Modares University | Habibi-Nokhandan M.,Climatological Research Institute
Atmospheric Pollution Research | Year: 2015

Spatial distribution modeling of CO in Tehran can lead to better air pollution management and control, and it is also suitable for exposure assessment and epidemiological studies. In this study MARS (Multi–variate Adaptive Regression Splines) is compared with typical interpolation techniques for spatial distribution modeling of hourly and daily CO concentrations in Tehran, Iran. The measured CO data in 2008 by 16 monitoring stations were used in this study. The Generalized Cross Validation (GCV) and Cross Validation techniques were utilized for the parameter optimization in the MARS and other techniques, respectively. Then the optimized techniques were compared based on the mean absolute of percentage error (MAPE). Although the Cokriging technique presented less MAPE than the Inverse Distance Weighting, Thin Plate Smooth Splines and Kriging techniques, MARS exhibited the least MAPE. In addition, the MARS modeling procedure is easy. Therefore, MARS has merit to be introduced as an appropriate method for spatial distribution modeling. The number of air pollution monitoring stations is very low (16 stations for 22 zones) and the distribution of stations is not suitable for spatial estimation, hence the level of errors was relatively high (more than 60%). Consequently, hourly and daily mapping of CO provides a limited picture of spatial patterns of CO in Tehran, but it is suitable for estimation of relative CO levels in different zones of Tehran. Hence, the map of mean annual CO concentration was generated by averaging daily CO distributions in 2008. It showed that the most polluted regions in Tehran are the central, eastern and southeastern parts, and mean annual CO concentration in these parts (zones 6, 12, 13, 14 and 15) is between 4.2 and 4.6 ppm. © Author(s) 2015. Source

Salahi-Moghaddam A.,Hormozgan University of Medical Sciences | Habibi-Nokhandam M.,Climatological Research Institute | Fuentes M.V.,University of Valencia
Geospatial Health | Year: 2011

Following human fascioliasis outbreaks in 1988 and 1999 in Gilan province, northern Iran, efforts are now made to shed light on the seasonal pattern of fascioliasis transmission in this endemic area, taking into account snail host populations, climatic conditions and human cases. Populations of the intermediate host snail (Lymnaea spp.) peak in May and November, while there is a fourfold increase in the rate of human fascioliasis in February compared to that of September. Transmission is likely to occur mainly in late autumn and sporadically in late spring. Rainfall, seasonally analysed in periods of 3 years, indicates that accumulated summer rainfall may be related with the 1988 and 1999 human fascioliasis outbreaks. Although a more detailed picture, based on the analysis of further abiotic and biotic factors influencing fascioliasis transmission in this area, is required to substantiate this hypothesis, our results serve as the first step of a geographical information system project concerning the epidemiological study of fascioliasis in Iran. This local-scale study concerning the effects of climate change and natural disasters on the spread of fascioliasis aims to facilitate the understanding of what goes on at the regional scale in this respect. Source

Barati M.,Tehran University of Medical Sciences | Keshavarz-Valian H.,Tehran University of Medical Sciences | Habibi-Nokhandan M.,Climatological Research Institute | Raeisi A.,Center for Diseases Management and Control | And 2 more authors.
Asian Pacific Journal of Tropical Medicine | Year: 2012

Objective: To conduct for modeling spatial distribution of malaria transmission in Iran. Methods: Records of all malaria cases from the period 2008-2010 in Iran were retrieved for malaria control department, MOH&ME. Metrological data including annual rainfall, maximum and minimum temperature, relative humidity, altitude, demographic, districts border shapefiles, and NDVI images received from Iranian Climatologic Research Center. Data arranged in ArcGIS. Results: 99.65% of malaria transmission cases were focused in southeast part of Iran. These transmissions had statistically correlation with altitude (650 m), maximum (30 °C), minimum (20 °C) and average temperature (25.3 °C). Statistical correlation and overall relationship between NDVI (118.81), relative humidity (45%) and rainfall in southeast area was defined and explained in this study. Conclusions: According to ecological condition and mentioned cut-off points, predictive map was generated using cokriging method. © 2012 Hainan Medical College. Source

Zarghami M.,University of Tabriz | Abdi A.,University of Tabriz | Babaeian I.,Climatological Research Institute | Hassanzadeh Y.,University of Tabriz | Kanani R.,East Azerbaijan Regional Water Company
Global and Planetary Change | Year: 2011

Changes in temperature and precipitation patterns have serious impacts on the quantity and quality of water supply, especially in arid regions. In recent years, frequent climatic droughts have threatened the water supply in East Azerbaijan Province, Iran. Because of the increasing demand for water, studying the potential climate change and its impacts on water resources is necessary. To predict the climate change based on the General Circulation Models (GCM), the successful downscaling tool of LARS-WG is applied. This stochastic weather generator downscaled the climate change of six synoptic stations in the province by using the HADCM3 model and three emission scenarios, A1B, A2 and B1, with the horizons 2020, 2055 and 2090. The research outcomes, based on the A2 scenario, show an average annual temperature rise of ~. 2.3°C and an annual precipitation reduction of ~. 3% in the middle of this century. These changes shift the climate of the province from semi-arid to arid based on the De Martonne aridity index. Using the artificial neural network (ANN), a model was then built to simulate the effects of climate change on the runoffs in three watersheds; the results showed dramatic reductions in the flows. The results of this study could advise the designers and managers of this region to take suitable actions in securing the water supply. © 2011 Elsevier B.V. Source

Salahi-Moghaddam A.,Hormozgan University of Medical Sciences | Mohebali M.,Tehran University of Medical Sciences | Moshfae A.,Tehran University of Medical Sciences | Habibi M.,Climatological Research Institute | Zarei Z.,Tehran University of Medical Sciences
Geospatial Health | Year: 2010

Between 1998 and 2001, a total of 1,062 human cases of visceral leishmaniasis were reported from the rural district of Meshkin-Shahr in the mountainous, north-western Iranian province of Ardabil. In the summer of 2008, a cross-sectional study of dogs was conducted in this endemic area by randomly selecting 384 animals from 21 villages and testing them serologically for leishmaniasis. Villages, in which more than 10% of investigated dogs showed anti- Leishmania titres ≥1/320, were considered to be high-risk environments. Regression analysis showed no statistically significant correlation between topographic conditions and the prevalence of positive cases. However, when the results were compared with past meteorological records, a statistically significant positive correlation (P = 0.007) was found between the number of infected dogs with anti-Leishmania titres ≥1/640 and the number of days in a year with temperatures below 0 °C. While humidity showed an inverse correlation (P = 0.009) with the anti-Leishmania titres, a positive correlation (P <0.001) was found in relation to the amount of rainfall. Mapping of the areas at risk for kala-azar in the Meshkin-Shahr district supports the impression that the low temperatures prevalent in the Ardebil province constitute an important factor influencing the distribution of leishmaniasis there. Source

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