Mastura Mahmud

Transboundary smoke haze pollution in Malaysia: Inpatient health impacts and economic valuation

This study assessed the economic value of health impacts of transboundary smoke haze pollution in Kuala Lumpur and adjacent areas in the state of Selangor, Malaysia. Daily inpatient data from 2005, 2006, 2008, and 2009 for 14 haze-related illnesses were collected from four hospitals. On average, there were 19 hazy days each year during which the air pollution levels were within the Lower Moderate to Hazardous categories. No seasonal variation in inpatient cases was observed. A smoke haze occurrence was associated with an increase in inpatient cases by 2.4 per 10,000 populations each year, representing an increase of 31 percent from normal days. The average annual economic loss due to the inpatient health impact of haze was valued at MYR273,000 (

Applying Advanced Ground-Based Remote Sensing in the Southeast Asian Maritime Continent to Characterize Regional Proficiencies in Smoke Transport Modeling

91,000 USD).

The performance of different cumulus parameterization schemes in simulating the 2006/2007 southern peninsular Malaysia heavy rainfall episodes

ABSTRACTThis work describes some of the most extensive ground-based observations of the aerosol profile collected in Southeast Asia to date, highlighting the challenges in simulating these observations with a mesoscale perspective. An 84-h WRF Model coupled with chemistry (WRF-Chem) mesoscale simulation of smoke particle transport at Kuching, Malaysia, in the southern Maritime Continent of Southeast Asia is evaluated relative to a unique collection of continuous ground-based lidar, sun photometer, and 4-h radiosonde profiling. The period was marked by relatively dry conditions, allowing smoke layers transported to the site unperturbed by wet deposition to be common regionally. The model depiction is reasonable overall. Core thermodynamics, including land/sea-breeze structure, are well resolved. Total model smoke extinction and, by proxy, mass concentration are low relative to observation. Smoke emissions source products are likely low because of undersampling of fires in infrared sun-synchronous satellite...

Precipitation assessment of a superensemble forecast over South‐East Asia

The performance of four different cumulus parameterization schemes (CPS) in the Weather Research and Forecasting (WRF) model for simulating three heavy rainfall episodes over the southern peninsular Malaysia during the winter monsoon of 2006/2007 were examined. The modelled rainfall was compared with the 3-hourly satellite observation and objectively scored using a verification technique called the acuity–fidelity. The technique is based on minimization of a cost function that is calculated from four parameters taking into account errors in distance, time, intensity, and missed events. All simulations were made for 72 hours for the three episodes starting at 1200 UTC 17 December 2006, 1200 UTC 24 December 2006 and 1200 UTC 11 January 2007, respectively. The four different CPSs used are the new Kain–Fritsch scheme (KF2), the Betts–Miller–Janjic scheme (BMJ), the Grell–Devenyi ensemble scheme (GD) and the older Kain–Fritsch scheme (KF1). While the BMJ scheme shows some success in the second and third episodes, it shows high location errors in the first episode, leading to high acuity errors. The GD, KF2 and KF1 schemes performed poorly, although both the BMJ and GD schemes simulated the observed drastic increase of rainfall at 2100 UTC 18 December 2006 during the first episode. Overall, the KF1 and KF2 schemes produced positive biases in terms of coverage, while the GD scheme showed persistent location bias, producing a scattered line of precipitation over the eastern coastline of peninsular Malaysia. Although the BMJ scheme has better results, its poor performance for the first episode suggests that suitability of CPS may be case dependent.

Prediction and simulation of Malaysian forest fires by random spread

A superensemble forecast that consists of six operational general circulation models is tested to simulate weather parameters over the equatorial South-East Asian region. The forecast technique, developed at Florida State University, is a unique ensemble that has proved to be one of the better prognosticators for weather forecasting. In this paper, the root mean square errors of the superensemble precipitation for a case of a severe tropical rainfall event during the winter monsoon of 2001 were smaller than the other global operational member or ensemble models used, indicating a skilled forecast. This trait is also reflected in the equitable threat score which indicates the association of the common rainfall threshold distribution between the forecast and observed best rainfall analysis from the Tropical Rainfall Measurement Mission (TRMM) and Special Sensor Microwave Imager (SSM/I) dataset, where although it is slightly underpredicted for light rain thresholds, its results are still superior to other individual member or even the ensemble mean forecasts. Higher correlation between the superensemble forecast and the observed is maintained for up to 3-day forecasts, which indicates its potential as a reliable and good forecast tool for predicting equatorial precipitation. Copyright

Peristiwa El Nino, keragaman hujan dan potensi Southern Oscillation Index untuk peramalan kualiti udara di Malaysia

This paper aims to study forest fires from risk maps and satellite data in order to predict the location of the burnt zones they provoke. The approach is based on the discrete stochastic model of a random spread, which describes both fire fronts and burnt areas. Under iteration, it provides the time evolution of the process. The probabilities of spontaneous extinction at each stage are derived. The random spread model is then applied to analyse the fires that occurred in the State of Selangor (Malaysia) from 2001 to 2004. It is used, first, to simulate forest fires, according to a law of intensity (fuel combustion) and another of extension (spread rate). But the next, and more important, result lies in the ability of the model to predict all places where burnt scars actually occurred, which turns out to be a significant verification.

PUBLIC PERCEPTION ON TRAFFIC POLLUTION IN FEDERAL TERRITORY OF KUALA LUMPUR, MALAYSIA

Abstrak Kejadian peristiwa El Nino mempengaruhi taburan hujan di Malaysia dan memberi impak terhadap kekurangan bekalan air untuk masyarakat umum serta kegiatan pertanian. Kajian ini bertujuan untuk mengkaji pola kejadian El Nino dan hubungannya dengan hujan yang diterima serta kesan keadaan kering yang menjejaskan kualiti udara di Malaysia. Data taburan hujan selama 38 tahun dari 1970 hingga 2008 di 12 buah stesen kajicuaca utama di Malaysia dianalisis dengan menggunakan kaedah statistik korelasi, bivariat dan multivariat. Hasil kajian mendapati korelasi antara min tahunan Equatorial Southern Oscillation Index (EQSOI), Southern Oscillation Index (SOI) dan Oceanic Nino Index (ONI), iaitu indeks untuk mengukur El Nino dan jumlah taburan hujan adalah negatif tapi lemah untuk EQSOI dan ONI, tapi positif untuk SOI. Penurunan jumlah taburan hujan di barat Semenanjung Malaysia tidak terlalu ketara berbanding yang dicatatkan di stesen Malaysia Timur. Korelasi antara indeks pencemaran udara dan hujan adalah negatif kecuali di Malaysia Timur (julat antara 0.07 hingga -0.43) yang menunjukkan bahawa dalam keadaan El Nino, kualiti udara di Malaysia lazimnya rendah kerana keadaan yang lebih kering. Analisis regresi multivariat menunjukkan bahawa kualiti udara dapat diramalkan daripada parameter hujan, EQSOI dan SOI, walaupun kebaikan suai berjulat antara 7% hingga 34% sahaja. Implikasi kajian ini adalah perancangan di peringkat pihak berkuasa untuk mengatasi peristiwa jerebu tempatan yang disebabkan oleh pencemaran setempat atau pencemaran rentas sempadan terutama sewaktu keadaan kering berpanjangan yang melanda negara akibat daripada fenomena El Nino. Kata kunci : El Nino, EQSOI, keragaman hujan, ONI, ramalan pencemaran udara, SOI Abstract The occurrence of El Nino events affects the rainfall in Malaysia and has an impact on the shortage of water supply for the general public as well as agricultural activities. This study aims to investigate the patterns of El Nino incidences and its relation to the rain received and the effects of the dry conditions on the air quality in Malaysia. Rainfall data for 38 years from 1970 to 2008 in 12 major meteorological stations in Malaysia were analyzed using correlation, bivariate and multivariate statistical methods. The results showed that the correlation between the mean annual Equatorial Southern Oscillation Index (EQSOI), the Southern Oscillation Index (SOI) and the Oceanic Nino Index (ONI), the index for measuring El Nino and the amount of rainfall was negative but weak for EQSOI and ONI, but positive for SOI. The decrease in the rainfall received in the west of Peninsular Malaysia was not significant compared to that recorded in the East Malaysia. The correlation between the air pollution index and the rainfall was negative except in East Malaysia (ranging between 0.07 and -0.43), indicating that during El Nino, air quality in Malaysia was usually low due to drier conditions. Multivariate regression analysis showed that air quality can be predicted from rainfall, EQSOI and SOI parameters, although the goodness of the fit ranged from only 7% to 34%. The results of this study implied that planning at the authority level is necessary to overcome the local haze events caused by local pollution or transboundary pollution, especially during prolonged dry conditions that hit the country due to the El Nino phenomenon. Keywords : El Nino, EQSOI, rainfall, ONI, air quality prediction, SOI https://doi.org/10.17576/geo-2018-1402-02

Characterization of spatial and temporal variability in hydrochemistry of Johor Straits, Malaysia.

Increasing pollutant emission from vehicles and traffic jams is a serious environmental problem in major cities. This study is focused on the level of public perception and awareness on traffic pollution in the capital city of the Federal Territory of Kuala Lumpur, Malaysia. Analytical tools such as descriptive analysis were applied to investigate the percentage of public perception and awareness towards traffic pollution and identify factors that influence this problem. Results showed that almost all respondents (99%) were very sensitive and were aware on traffic pollution regarding the physical, nonphysical factors and the health effect. Most respondents indicated that emissions from exhaust after switching on was the major contributor of air pollution. In terms of health, respondents perceived that traffic pollution impacted health and a cause of illness. Most respondents agreed with initiatives that provide incentives for public transport usage so that emission from vehicles can be reduced significantly.

Observing and understanding the Southeast Asian aerosol system by remote sensing: An initial review and analysis for the Seven Southeast Asian Studies (7SEAS) program

Characterization of hydrochemistry changes in Johor Straits within 5 years of monitoring works was successfully carried out. Water quality data sets (27 stations and 19 parameters) collected in this area were interpreted subject to multivariate statistical analysis. Cluster analysis grouped all the stations into four clusters ((Dlink/Dmax) × 100<90) and two clusters ((Dlink/Dmax) × 100<80) for site and period similarities. Principal component analysis rendered six significant components (eigenvalue>1) that explained 82.6% of the total variance of the data set. Classification matrix of discriminant analysis assigned 88.9-92.6% and 83.3-100% correctness in spatial and temporal variability, respectively. Times series analysis then confirmed that only four parameters were not significant over time change. Therefore, it is imperative that the environmental impact of reclamation and dredging works, municipal or industrial discharge, marine aquaculture and shipping activities in this area be effectively controlled and managed.