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Due to lack of observational studies on greenhouse gases in Malaysia, most studies in this field were carried out based on ground station data. These studies did not utilize satellite data from the equatorial area. Satellite remote sensing is one of the most effective approaches for greenhouse gas distribution monitoring on a global scale. As such,...
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... is located in Southeast Asia (south of Thailand, north of Singapore, and east of the Indonesian island of Sumatra). The area of Peninsular Malaysia is approximately 131 587 km 2 , with an esti- mated population of 21 million (Tan et al., 2010) (Figure 1). The five selected sites are presented in Table 1. ...
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... But these studies are limited to the polar region only (Newman et al., 2006). Such studies have been extended for other locations of the globe and established statistical trends of TCO over the northern and southern mid-latitudes (Toihir et al., 2018;Badawy et al., 2017;Tan et al., 2014;Nair et al., 2013;Oluleye and Okogbue, 2013;Stein, 2007;Chakrabarty et al., 1998;Rowland, 1991). These studies suggest that the depletion of ozone is not only confined in the Polar Regions but varies significantly in another latitudinal region as well. ...
Total Column Ozone (TCO) is a critical factor affecting the earth’s atmosphere,
especially in the Himalayan region. A comprehensive study of TCO trend analysis
and corresponding consequences in the Himalayan atmosphere needs to be analyzed.
We statistically examine TCO variability by analyzing the daily TCO dataset of the last 15
years (2005-2019) over the crucial region of the Himalayan environment i.e. Uttarakhand,
India. Obtained results indicate that TCO values are at peak during the spring season
whereas it shows the least value during the winter season. The highest and lowest
value of Coefficient of Relative Variance (CRV) is estimated as 3.14 and 1.09 during winter
and monsoon season, respectively. Air mass trajectories have been estimated using
Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT), which shows the existence
of strong seasonal variability of Ozone corresponding to continental and maritime
transportation towards Uttarakhand. Moreover, Least Square Method (LSM) and the
Mann-Kendall test estimate a high correlation (86%) for the seasonal and annual trend of
TCO with a negative rate. The obtained decreasing rate is very low which indicates recovery
of TCO during the study period. Further results imply that the inter-annual oscillation
pattern of TCO is similar to Quasi-Biennial Oscillation (QBO) significantly. In addition, a
comparative study has been performed for the data measured by two TCO measuring
instruments i.e. Ozone Monitoring Instrument (OMI) and Ozone Mapping Profiler Suite
(OMPS). TCO values measured from both instruments are highly correlated (96%) with an
average relative difference of around 3%. The outcomes of this study are expected to be
beneficial for future study of TCO over other crucial regions of Himalayan territory.
... Such studies have been extended for other locations of the globe and established statistical trends of TCO over the northern and southern mid-latitudes (Rowland et al., 1991;Chakrabarty et al., 1998;By Michael L. et al., 2007;P. J. Nair et al., 2013;Ayodeji Oluleye et al., 2013;Kok Chooi Tan et al., 2014;A. Badawy et al., 2017). ...
Total Column Ozon is a critical factor affecting the earths atmosphere, especially in the Himalayan region. A comprehensive study of TCO trend analysis and corresponding consequences in the Himalayan atmosphere needs to be analyzed. We statistically examine TCO variability by analyzing the daily TCO dataset of the last 15 years i.e.2005-2019 over the crucial region of the Himalayan environment i.e. Uttarakhand, India. The outcomes of this study are expected to be beneficial for future study of TCO over other crucial regions of Himalayan territory.
... It is considered as a primary precursor for the production of hydroxyl radical (OH), that acts as an oxidizing agent severely disturbing the occurrence of tropospheric trace gases (Seinfeld and Pandis, 2016). TropoO3 absorbs short-wave solar radiations and after attenuation re-radiates it in the form of long-wave radiations (Shan et al., 2008;Pal, 2010;Tan et al., 2014). TropoO3 has harmful effects on human health, vegetation health & yield, and sensitive ecosystems (EPA, 2003; The Royal Society, 2008; Avnery et al., 2011;Burney and Ramanathan, 2014). ...
... Issues on O 3 status and variation are also found as the other topics of interest. Among the studies that have been conducted, in [5] were also supported by the publication of [6]. Among the studied areas, other than Shah Alam, ...
... The combination of nearby oxygen molecules and these atoms to form a three-oxygen molecule. Besides, O 3 also well-known as secondary pollutant in the atmosphere, which is a resultant of photochemical reaction due to anthropogenic and natural precursors like volatile organic compounds (VOCs) and oxides of nitrogen (NOx) [2,3]. ...
... In 2015, the haze become worse due to extreme weather conditions caused by El Niño raise the ocean temperature in Southern Ocean. El Niño has delayed the monsoon rains in Indonesia thus, leading to drought across the country [19]. Asian continent experienced summer season, while Australian continent experienced winter season during SWM. ...
Total column ozone obtained from the Ozone Monitoring Instrument (OMI) on board the Aura satellite was utilized to examine the spatial and temporal distribution of atmospheric ozone over Peninsular Malaysia for the year of 2015. The monthly ozone maps were obtained from the NASA-operated Giovanni portal (http://disc.sci.gsfc.nasa.gov/giovanni). Ozone has an inverse relationship with the rain and positive with temperature. The fluctuation in the ozone values during the Northeast monsoon and Southwest monsoon seasons was caused by the variations of the number of sunny days, the variations of the precipitation, greater cloud cover which were influenced by the effects of biomass burning in several provinces in Sumatera and Kalimantan, Indonesia, emissions from motor vehicles and trans-boundary pollution. The ozone fluctuated considerably observed between Southwest monsoon and Northeast monsoon seasons through the analysis of ozone for the desired study area. For seasonal variability, the trend of total column ozone shows a distinct seasonal pattern, with maximum in August or September and minimum in December or January. For upcoming studies, validation of satellite ozone data with in situ measurements and study of tropospheric ozone over this region is recommended.
... Ozone (O 3 ) is secondary pollutant formed by a photochemical reaction among volatile organic compounds (VOCs) and nitrogen oxides (NO x ) in the atmosphere (Castell-Balaguer et al., 2012;Tan et al., 2014a). O 3 plays an important role in the atmospheric process and influences the environment and human health depending on its location in the atmosphere. ...
... Because of its geographical location near the equator, Peninsular Malaysia experiences a humid tropical climate throughout the year; the weather in this area is warm and humid with temperatures ranging from 20 C to 32 C (Tan et al., 2014a). The tropical climate in this region is considerably influenced by mountainous topography and complex landesea interactions. ...
The aim of this study is to develop new algorithms of the column ozone (O3) in Peninsular Malaysia using statistical methods. Four regression equations, denoted as O3 NEM, O3 SWM, (PCA1) O3 NEM season, and (PCA2) O3 SWM season, were developed. Multiple regression analysis (MRA) and principal component analysis (PCA) methods were utilized to achieve the objectives of the study. MRA was used to generate regression equations for O3 NEM and O3 SWM, whereas a combination of the MRA and PCA methods were used to generate regression equations for PCA1 and PCA2. The results of the best regression equations for the column O3 through MRA by using four of the independent variables were highly correlated (R = 0.811 for SWM, R = 0.803 for NEM) for the six-year (2003–2008) data. However, the result of fitting the best equations for the O3 data using four of the independent variables gave approximately the same R values (≈0.83) for both the NEM and SWM seasons using the combined MRA and PCA methods. The common variables that appeared in both regression equations were H2O vapor and NO2. This result was expected because NO2 is a precursor of O3. The correlation coefficients (R) of the validation for the NEM and SWM seasons were 0.877–0.888 and 0.837–0.896, respectively. These statistical values indicated a very good agreement between the monthly predicted and observed O3 for Peninsular Malaysia.
... In Malaysia, previous studies have relied on ground station data due to the lack of observational greenhouse gas data since studies using satellite data have not considered equatorial areas (Tan et al., 2014a). In the last three years, however, there have been many studies employing greenhouse gas satellite data from Malaysia and equatorial areas. ...
... The climate in this region is considerably influenced by the mountainous topography and complex land-sea interactions. Intra-seasonal and intra-decadal fluctuations, such as the El Niño-Southern Oscillation, Indian Ocean Dipole, and Madden Julian Oscillation, significantly influence the inter-annual climatic variability of Malaysia (Tan et al., 2014a). The highest monthly average temperatures occur in April, May, July, and August whereas the lowest average monthly temperatures are recorded from November to January. ...
This study aims to predict monthly columnar ozone in Peninsular Malaysia based on concentrations of several atmospheric gases. Data pertaining to five atmospheric gases (CO2, O3, CH4, NO2, and H2O vapor) were retrieved by satellite scanning imaging absorption spectrometry for atmospheric chartography from 2003 to 2008 and used to develop a model to predict columnar ozone in Peninsular Malaysia. Analyses of the northeast monsoon (NEM) and the southwest monsoon (SWM) seasons were conducted separately. Based on the Pearson correlation matrices, columnar ozone was negatively correlated with H2O vapor but positively correlated with CO2 and NO2 during both the NEM and SWM seasons from 2003 to 2008. This result was expected because NO2 is a precursor of ozone. Therefore, an increase in columnar ozone concentration is associated with an increase in NO2 but a decrease in H2O vapor. In the NEM season, columnar ozone was negatively correlated with H2O (–0.847), NO2 (0.754), and CO2 (0.477); columnar ozone was also negatively but weakly correlated with CH4 (–0.035). In the SWM season, columnar ozone was highly positively correlated with NO2 (0.855), CO2 (0.572), and CH4 (0.321) and also highly negatively correlated with H2O (–0.832). Both multiple regression and principal component analyses were used to predict the columnar ozone value in Peninsular Malaysia. We obtained the best-fitting regression equations for the columnar ozone data using four independent variables. Our results show approximately the same R value (≈ 0.83) for both the NEM and SWM seasons.
... During the cold months, the amount of O 3 transported was greater than that due to local formation, with the opposite being true during warm months [140]. In Asia, O 3 episodes in Malaysia were attributed to regional transport from biomass burning in Sumatra, Indonesia, as well as long-range transport from Indo-China [141]. Moreover, transport, airflow pattern, stagnation, and the boundary layer height determined the concentrations recorded at certain sites in India and the Bay of Bengal [142][143][144][145][146][147][148]. ...
Air trajectory calculations are commonly found in a variety of atmospheric analyses. However, most of reported research usually focuses upon the transport of pollutants via trajectory routes and not on the trajectory itself. This paper explores the major areas of research in which air trajectory analyses are applied with an effort to gain deeper insights into the key points which highlight the necessity of such analyses. Ranging from meteorological applications to their links with living beings, air trajectory calculations become important tool especially when alternative procedures do not seem possible. This review covers the reports published during last few years illustrating the geographical distribution of trajectory applications and highlighting the regions where trajectory application research proves most active and useful. As a result, relatively unexplored areas such as microorganism transport are also included, suggesting the possible ways in which successful use of air trajectory research should be extended.
... Stratospheric ozone forms a gaseous envelope around the Earth which protects people and the environment from harmful ultraviolet radiations (λ ≤ 240 nm) coming from the outer space. On the other hand, tropospheric ozone is regarded as a strong greenhouse gas (GHG) that absorbs heat energy that is re-radiating off the Earth's surface in the form of long-wave radiations (Shan et al. 2008;Pal 2010;Tan, Lim, and MatJafri 2014). It has been well documented that tropospheric ozone has adverse impacts on human health and plants (Varotsos et al. 1995;Alexandris et al. 1999;Kiehl et al. 1999;Rex et al. 2004). ...
... It is also noticed that daily maximum values show a decreasing trend of −2.1%, whereas an increasing trend of 1.9% per decade is observed for daily minimum values. Atmospheric ozone is considered to be related positively with temperature and number of sun hours in a day, and its negative relation exists with amount of precipitation, humidity, and cloud cover (Camalier, Cox, and Dolwick 2007;Tu et al. 2007;Shan et al. 2009;Tan, Lim, and MatJafri 2014). It has been found that maximum monthly averaged TOC values occur during the months of March and April (Figure 4), ranging up to 290 DU. ...
... In this process, ozone is formed from atmospheric oxygen and ozone precursor pollutants (Finlayson, Barbara, and James 1999). These enhanced levels of ozone in these months are in confirmation with Tan, Lim, and MatJafri (2014). In the months of May through November, a decrease in TOC values from 287 to 264 DU is observed, mainly attributed to more air circulation, increasing rains in southern parts of Pakistan, decreasing temperatures, and increasing cloud cover from September to November in northern parts of Pakistan. ...
Total ozone column (TOC) obtained from the Ozone Monitoring Instrument (OMI) on
board the Aura satellite was utilized to examine the spatio-temporal distribution of atmospheric ozone over Pakistan and adjoining regions of Afghanistan, India, and Iran for
October 2004 to March 2014. This region has not yet been evaluated in greater detail. A
yearly spatial averaged value of 278 ± 2 DU was found over the region. A decadal increase
of 1.3% in TOC value over study region was observed for the first time. Large spatial and
temporal variability of TOC was found over the study region. Elevated ozone columns
were observed over the regions with high NO2 and CO concentrations. Analysis indicated
that Srinagar city has the highest averaged value of 290 ± 3 DU whereas Jodhpur city
showed the highest increasing trend of 1.9% per decade. A monthly averaged maximum
value of 289 ± 8 DU and a minimum of 264 ± 5 DU were found during April and
November, respectively, over the region. January showed a decreasing trend of −0.8%and
February exhibited the highest increasing trend of 5.1% per decade. Forward trajectory
analysis showed the possibility of ozone transport from eastern parts of the study region
towards the Indian Ocean (Bay of Bengal) through the subtropical jet stream creating low
values at higher meridians in October. TOC data deduced from OMI and the Atmospheric
Infrared Sounder were compared to check the level of correlation and the results showed
significant correlation (r = 0.75) and an acceptable average relative difference of 4.2%.
