Study on the measurements of total ozone column and ground-level ozone in DLSU-Manila from February to November 2011

• Main Author: Moreno, Francisco V., Jr.
• Format: text
• Language: English
• Published: Animo Repository 2012
• Subjects: Ozone—Measurement; Environmental Indicators and Impact Assessment; Environmental Monitoring
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/18604
• Institution: De La Salle University

Total ozone column (TOC) and ground-level ozone measurements were conducted in De La Salle University, Manila, Philippines (14.71° N, 121.58° E) from February 2011 to November 2011 using a hand-held Microtops II Ozonemeter (MII), the Thermo Ozone Analyzer (TECO), and the Opsis Differential Optical Absorption Spectrometer (DOAS). This study includes the first local measurements of total ozone column in the Philippines. Measurements using the device were taken during midday (local noontime) and when the sun is clearly seen. When compared to the total ozone column readings from the Ozone Monitoring Instrument (OMI) satellite, the Microtops II yielded a difference of approximately 3-15%. The "MII Ozone Spectrophotometer provided data of the TOC averaging 280.36 ± 15.13 Dobson units (DU) while OMI TOC data obtained an average of 262.23 ± 19.26 DU. For the ground-level ozone, the instruments took measurements 24 hours a day from March 2011 until September 2011. The TECO measurements showed how the various seasonal changes in photochemical activity vary the production of ozone. Analyses have shown that averaged point concentration of ozone was at its maximum during summer, April 2011 at 25.36 ppb, and was at its minimum in September 2011 at 8.25 ppb during the rainy season. The DOAS, on the other hand, yielded results that peaked in November 2011 at I 9.57 ppb. The DOAS instrument was only used from July 2011 until November 2011 only.