The present study investigated NO3- and Br- contamination in groundwater of Arak aquifer, Markazi province, Iran. Correlation and factor analyzes were used to detecti nterrelations and sources of NO3- and Br- ion concentration and other physicochemical variables. No correlation was observed between NO3- and otherscontents, but a positive correlation was identified between Br-and other majorvari...

We use ground-based observations of CO mixing ratios and vertical column abundances together with tropo-spheric NO 2 columns from the GOME satellite instrument as constraints for improving the global annual emission estimates of CO and NO x for the year 1997. The agreement between concentrations calculated by the global 3-dimensional CTM IMAGES and the observations is optimized using the adjoin...

Urban water systems are impacted by land use within their source watersheds, as it affects raw water quality and thus the costs of water treatment. However, global estimates of the effect of land cover change on urban water-treatment costs have been hampered by a lack of global information on urban source watersheds. Here, we use a unique map of the urban source watersheds for 309 large cities ...

Stable sulfur isotope measurements (delta34S) made on samples collected from a 2 m snowpit on the Inilchek Glacier, Tien Shan Mountains (42.16 degrees N, 80.25 degrees E, 5100 m) are used to estimate sources of sulfate (SO4(2-)) in high-elevation Central Asian precipitation. Comparison of snowpit oxygen isotope (delta18O) data with previous work constrains the age of the snowpit samples to the ...

We use observed CO2:CO correlations in Asian outflow from the TRACE-P aircraft campaign (February-April, 2001), together with a 3-D global chemical transport model (GEOS-CHEM), to constrain specific components of the East Asian CO2 budget including, in particular, Chinese emissions. The CO2/CO emission ratio varies with the source of CO2 (different combustion types vs. the terrestrial biosphere...

We use aircraft observations of carbon monoxide (CO) from the NASA ARCTAS and NOAA ARCPAC campaigns in April 2008 together with multiyear (2003– 2008) CO satellite data from the AIRS instrument and a global chemical transport model (GEOS-Chem) to better understand the sources, transport, and interannual variability of pollution in the Arctic in spring. Model simulation of the aircraft data give...

background: soil serves as a major reservoir for contaminants as it can bind to various chemicals. the aim of this study was to evaluate the levels of some metals (cd, cu, fe and v) in soil samples collected from different stations of ahvaz industrial complex ii to determine the natural and anthropogenic contribution of metal in the soil. methods: this was an experimental study that carried out...

in the recent years, sediments are used for the assessment of pollution. since sediments have been in contact for a long time with over lying water, therefore they have been able to adsorb pollution on to their surface. in the present investigation, the surficial sediments of siahrud river have been analyzed. the loose, sulphide and organic bonds of metals with various sedimentary phases has be...

Satellite observations of formaldehyde (HCHO) columns provide top-down constraints on emissions of highly reactive volatile organic compounds (HRVOCs). This approach has been used previously in the US to estimate isoprene emissions from vegetation, but application to anthropogenic emissions has been stymied by lack of a discernable HCHO signal. Here we show that temporal oversampling of HCHO da...