1 / 1

A.M. Córdova 1 , Melitta Fiebig-Wittmaack 1,2,3 , J. Quintana 4 , L. Valle 4 and G. Torres 4

Cerro Tololo. La Niña. El Niño. Frecuency of wind direction at Cerro Tololo. CLIMATOLOGICAL ANALYSIS OF OZONE AND RADIATION MEASUREMENTS AT A BACKGROUND SITE IN THE SOUTHERN HEMISPHERE SUBTROPICS: Cerro Tololo 30ºS,70ºW, 2200 m.a.s.l.

leann
Download Presentation

A.M. Córdova 1 , Melitta Fiebig-Wittmaack 1,2,3 , J. Quintana 4 , L. Valle 4 and G. Torres 4

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cerro Tololo La Niña El Niño Frecuency of wind direction at Cerro Tololo CLIMATOLOGICAL ANALYSIS OF OZONE AND RADIATION MEASUREMENTS AT A BACKGROUND SITE IN THE SOUTHERN HEMISPHERE SUBTROPICS: Cerro Tololo 30ºS,70ºW, 2200 m.a.s.l. A.M. Córdova 1, Melitta Fiebig-Wittmaack1,2,3, J. Quintana4, L. Valle 4 and G. Torres 4 1.Centro de Estudios Avanzados en Zonas Áridas (CEAZA) , Benavente 980, Casilla 599, La Serena, Chile. acordova@inia.cl 2.Departamento de Matemática, Universidad de La Serena, Chile. 3.Centro de Investigación Atmosférica , La Serena (CIALS), Chile 4. Dirección Meteorológica de Chile INTRODUCTION Several chemical and dynamical processes regulate surface ozone (O3) concentrations. Measurements of ultraviolet spectral irradiance, tropospheric ozone and meteorological parameters (temperature, wind speed and direction, relative humidity, etc) have been performed simultaneously at Cerro Tololo (CT) (30º 10´S, 70º 48´O, 2200 m.a.s.l.) by the Chilean Weather Office as part of the Global Atmospheric Watch (GAW) program of the World Meteorological Organization (WMO) since November 1995. • RESULTS AND DISCUSSION • The ozone concentrations ranged from 11 ppb to 60 ppb. Results showed that O3 concentrations measured during summer (DJF) were lower than spring season (SON) at Cerro Tololo. • The average ozone concentrations do not show significant diurnal cycle at this site. The ozone concentrations during summer and autumn are 27 ppb (SD  5.2 ppb). The increase of ozone concentrations are observed during of month of spring (SON) with the maximum concentration of 60 ppb. The maximum solar radiation decrease from 1100 Wm-2 in summer (DJF) to 620 Wm-2in winter (JJA). • Ozone concentrations do not show a positive correlation with solar and UV-B radiation. This indicates that in situ photochemical production is not the driving process at this site. In fact that, previous work suggest that synoptical features linked with stratosphere-troposphere exchange play a significant role in explaining the spring maximum and the sudden increases in ozone mixing ratios observed at Cerro Tololo. • The index UV is higher than 11 (exposure category = extreme) from November to February. • Ozone concentrations do not show correlations with wind speed and wind direction at surface. The wind direction is principally from Northeast during all year. • A inspection of the data do not shows temporal trends and ENOS do not influence significantly the ozone concentrations at this site. On the other hand, no significant change of O3was observed in association to the El Niño 1997 and La Niña 1998. Acknowledgements : Dirección Meteorólogica de Chile (DMC), Chilean Research Council (CONICYT-FONDECYT 1030809).

More Related