Publicaciones 2011-2020

@article{RN374,
title = {Trend and Recovery of the Total Ozone Column in South America and Antarctica},
author = { R. Toro and C. Araya and F. Labra and L. Morales and R.G.E. Morales and M.A. Leiva},
url = {/brokenurl#<Go to ISI>://WOS:000415579000006},
doi = {10.1007/s00382-017-3540-1},
issn = {0930-7575},
year = {2017},
date = {2017-01-01},
journal = {Climate Dynamics},
volume = {49},
number = {11-12},
pages = {3735-3752},
abstract = {South America is one of the most vulnerable areas to stratospheric ozone depletion; consequently, an increased amount of UV radiation reaches the Earth's surface in this region. In this study, we analyzed the long-term trend in the total ozone column (TOC) over the southern part of the South American continent from 1980 to 2009. The database used was obtained by combining several satellite measurements of the TOC on a 1A degrees (latitude) x 1.25A degrees (longitude) grid. Analysis of the long-term trend was performed by applying the Theil-Sen estimator and the Mann-Kendall significance test to the deseasonalized time series. The long-term trend was also analyzed over several highly populated urban zones in the study area. Finally, multiple linear regression (MLR) modeling was used to identify and quantify the drivers of interannual variability in the TOC over the study area with a pixel-by-pixel approach. The results showed a decrease in the TOC ranging from -0.3 to -4% dec(-1) from 1980 to 2009. On a decadal timescale, there is significant variability in this trend, and a decrease of more than -10% dec(-1) was found at high latitudes (1980-1989). However, the trends obtained over much of the study area were not statistically significant. Considering the period from 1980 to 1995, we found a decrease in the TOC of -2.0 +/- 0.6% dec(-1) at latitudes below 40A degrees S and -6.9 +/- 2.0% dec(-1) at latitudes above 40A degrees S, for a 99.9% confidence level over most of the study area. Analysis of the period from 1996 to 2009 showed a statistically significant increase of 2.3 +/- 0.1% dec(-1) at high latitudes (> 60A degrees S), confirming the initial TOC recovery in the Antarctic. Despite evidence for initial recovery of the TOC in some parts of the study area between 1996 and 2009, the long-term increase from September to November is not yet statistically significant. In addition, large parts of the study area and most of the urban areas continue to show a decreasing trend in the TOC. The MLR results show that at high latitudes, the main driver of interannual variability in the TOC is the total effective amount of halogens, followed by the eddy heat flux.},
keywords = {analysis, arosa atmospheric chemistry, column, cycle, decadal depletion, dynamics, environmental chemistry, estimator, events, extratropical extreme interannual linear long-term multiple oscillation, ozone ozone, punta-arenas, quasi-biennial regression, sunspot theil-sen total trend variability, variation},
pubstate = {published},
tppubtype = {article}
}

@article{RN219,
title = {Photochemical Ozone Pollution in the Valparaiso Region, Chile},
author = { R. Toro and C.S. Donoso and R.A. Seguel and R.G.E. Morales and M.A. Leiva},
url = {/brokenurl#<Go to ISI>://WOS:000332712300001},
doi = {10.1007/s11869-013-0218-7},
issn = {1873-9318},
year = {2014},
date = {2014-01-01},
journal = {Air Quality Atmosphere and Health},
volume = {7},
number = {1},
pages = {1-11},
abstract = {The Valparaiso Region is characterized by the presence of air sheds that modulate the general atmospheric circulation with local winds. The ozone concentration in the region increases from the west coast toward the mountainous area, where the concentrations of ozone precursors are lower. In this study, surface ozone (O-3), nitric oxide, nitrogen dioxide, nitrogen oxide (NO (x) ), and volatile organic compounds (VOCs) were measured at four sites, including two upwind urban sites (Via del Mar (VM) and Villa Alemana (VA)), an upwind suburban site (Quillota (QU)) and a downwind semirural site (Los Andes (LA)) during 01 March-07 April 2010. The purpose of this study is to improve our understanding of the photochemistry of ozone in urban and semirural areas of the Valparaiso Region and the transport of ozone pollution in downwind rural areas. The results show that, in the VM and VA sites, higher concentrations of ozone precursors, NO (x) , and VOCs, are observed in the early morning hours, which is related to emissions from vehicle traffic, while comparatively lower ozone precursor concentrations are observed in QU and LA. In contrast, higher ozone concentrations are found in LA and QU, and lower concentrations are found in VM and VA. VOC analysis was performed by gas chromatography, and the results show that the VOC composition in the studied sites is similar to and coincident with vehicle emissions. An ozone formation regime limited by VOCs is found in the area. The leading contributors to the ozone-forming potential were ethene, propene, xylene, and toluene, which are also anthropogenic species and account for more than 70 % of O-3 formation. Thus, benzenes-toluene-xylenes played the most important role in O-3 formation, followed by alkenes, alkanes, aromatic, biogenic, and alkynes during the study periods. The m-, p-xylene/ethylbenzene relation confirms the reception of aged air masses in LA. The results of the present study demonstrate that ozone pollution is a regional problem and that O-3 regional transport is associated with such pollution. Finally, the results indicate the need to adopt mitigating measures for ozone pollution that consider the reactivity characteristics of VOCs.},
keywords = {control emissions, environmental chemistry, episode, formation hydrocarbons, non-methane nox, organic-compounds, ozone ozone, pollution-urban potential, regional, strategy, tropospheric volatile},
pubstate = {published},
tppubtype = {article}
}