نتایج جستجو برای: surface ozone

تعداد نتایج: 653219  

2015
Andra J. Reed Anne M. Thompson Debra E. Kollonige Douglas K. Martins Maria A. Tzortziou Jay R. Herman Timothy A. Berkoff Nader K. Abuhassan Alexander Cede

An analysis is presented for both ground- and satellite-based retrievals of total column ozone and nitrogen dioxide levels from the Washington, D.C., and Baltimore, Maryland, metropolitan area during the NASA-sponsored July 2011 campaign of Deriving Information on Surface COnditions from Column and VERtically Resolved Observations Relevant to Air Quality (DISCOVER-AQ). Satellite retrievals of t...

2013
Seok-Woo Son Ariaan Purich Harry H. Hendon Baek-Min Kim Lorenzo M. Polvani

[1] Southern Hemisphere (SH) climate change has been partly attributed to Antarctic ozone depletion in the literatures. Here we show that the ozone hole has affected not only the long-term climate change but also the interannual variability of SH surface climate. A significant negative correlation is observed between September ozone concentration and the October southern annular mode index, res...

2011
H. He D. W. Tarasick W. K. Hocking T. K. Carey-Smith Y. Rochon J. Zhang P. A. Makar M. Osman J. Brook M. D. Moran D. B. A. Jones

Twice-daily ozonesondes were launched from Harrow, in southwestern Ontario, Canada, during the BAQSMet (Border Air Quality and Meteorology Study) field campaign in June and July of 2007. A co-located radar windprofiler measured tropopause height continuously. These data, in combination with continuous surface ozone measurements and geo-statistical interpolation of satellite ozone observations, ...

2016
Jeffrey A. Geddes Colette L. Heald

Anthropogenic land use change (LUC) since preindustrial (1850) has altered the vegetation distribution and density around the world. We use a global model (GEOSChem) to assess the attendant changes in surface air quality and the direct radiative forcing (DRF). We focus our analysis on secondary particulate matter and tropospheric ozone formation. The general trend of expansion of managed ecosys...

2008
Susan Kemball-Cook David Parrish Thomas Ryerson Uarporn Nopmongcol Jeremiah Johnson Edward Tai Greg Yarwood

[1] During the 2000 Texas Air Quality Study (TexAQS) and 2006 Texas Air Quality Study (TexAQS II) field experiments, aircraft measured ozone concentrations upwind, across, and downwind of the Houston and Dallas urban areas. Background ozone transported into Houston contributed, on average, approximately 50% and 66% of the total ozone on 8-h ozone exceedance days investigated by aircraft flights...

2000
Zhanqing Li Pucai Wang Josef Cihlar

A continual trend of ozone depletion has drawn much attention to the biologically harmful UV-B radiation from the Sun reaching the Earth’s surface. Satellite remote sensing provides a sole means of monitoring the global distribution of surface UVB. At present, there are very few inversion algorithms with sufficient accuracy and robustness for operational application. A new algorithm is proposed...

2005
Robert F. Whitehead Stephen J. de Mora Serge Demers

UV irradiance at the earth’s surface is intimately related to stratospheric ozone. This gas tends to be concentrated in the lower stratosphere (hence the notion of an ozone layer) and is primarily responsible for the absorption of solar UV radiation (UVR). UVR has been recognised for many years (e.g. Worrest, Dyke & Thomson, 1978; Worrest et al., 1981; Calkins, 1982) as a potential stress for o...

2004
D. J. Jacob O. R. Cooper M. J. Evans C. L. Heald R. J. Park R. C. Hudman F. Fehsenfeld F. Flocke J. Holloway G. Hübler K. Kita M. Koike Y. Kondo A. Neuman J. Nowak S. Oltmans D. Parrish J. M. Roberts

[1] We examine the ozone production efficiency in transpacific Asian pollution plumes, and the implications for ozone air quality in California, by using aircraft and surface observations in April–May 2002 from the Intercontinental Transport and Chemical Transformation 2002 (ITCT 2K2) campaign off the California coast and the Pacific Exploration of Asian Continental Emission–B (PEACE-B) campaig...

2009
K. Tourpali A. F. Bais A. Kazantzidis C. S. Zerefos M. A. Giorgetta D. E. Kinnison E. Mancini D. R. Marsh

We have estimated changes in surface solar ultraviolet (UV) radiation under cloud free conditions in the 21st century based on simulations of 11 coupled ChemistryClimate Models (CCMs). The total ozone columns and vertical profiles of ozone and temperature projected from CCMs were used as input to a radiative transfer model in order to calculate the corresponding erythemal irradiance levels. Tim...

Journal: :Science 1993
D D Parrish J S Holloway M Trainer P C Murphy F C Fehsenfeld G L Forbes

Measurement of the levels of ozone and carbon monoxide (a tracer of anthropogenic pollution) at three surface sites on the Atlantic coast of Canada allow the estimation of the amount of ozone photochemically produced from anthropogenic precursors over North America and transported to the lower troposphere over the temperate North Atlantic Ocean. This amount is greater than that injected from th...

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