THE MONITORING ACTIVITIES AT GAW STATIONS IN MALAYSIA

INTRODUCTION

The air quality monitoring network presently comprises of 23 stations, which 17 are located in Peninsular Malaysia, 4 in Sabahand 2 in Sarawak.

3 Global Atmosphere Watch (GAW) stations: Regional (Developing Rural Site) - Cameron Highlands, Pahang Regional (Urban Site) - Petaling Jaya, Selangor Global (Forest Site) - Danum Valley, Sabah

Maznorizan Mohamad, Toh Ying Ying, Mohd Firdaus Jahaya, Nur Aleesha Abdullah, Norazura Zakaria, Ng Chee Wah & Leong Kok PengEnvironmental Studies Division, Malaysian Meteorological Department, Ministry of Science, Technology and Innovation, MALAYSIA

THE GAW STATIONS IN MALAYSIAGlobal GAW Station Danum Valley Location: Lembah Danum, Lahad Datu, Sabah Forest site (Global/Baseline GAW) Latitude: 04° 58‘ 53" North Longitude: 117° 50‘ 37" East Altitude: 426 m above Mean Sea Level (MSL) - Atur Hill Within the 973 km2 forest reserve (managed by the Sabah

Foundation) Construction work began in 2002 under the 8th Malaysian

Development Plan Started operating in November 2003

Regional GAW Station Cameron Highlands Location: Tanah Rata, Cameron Highlands, Pahang Developing rural site (mountainous region) Latitude: 04° 28’ North Longitude: 101° 23’ East Altitude: 1545 m above Mean Sea Level (MSL)

Regional GAW Station Petaling Jaya Location: Petaling Jaya, Selangor Urban site Latitude: 03° 6’ North Longitude: 101° 39’ East Altitude: 87 m above Mean Sea Level (MSL)

MONITORING PROGRAMMES IN GAW STATIONS

Wet Only Sampler APS Filter Pack Passive Sampler

LoFlo Mark II CO2

Brewer TEOM

Flask Sampling

HVAS PM-10

O3 Analyzer

XAD

PUF Disk

Multigas AnalyzerPFR AWS MAAPNephelometerHVAS TSP

COLLABORATION AND COOPERATION WITH INTERNATIONALSCIENTIFIC COMMUNITY Twinning Programme with World Calibration Center for Physical Aerosol Properties (WCCPAP) -

Institute for Tropospheric Research, Germany

National Institute of Environmental Studies (NIES), Japan - flask sampling

Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia - LoFlo Mark IICO2

Collaboration with the Environment Canada on the Global Atmosphere Passive Sampling (GAPS)programme - Persistent Organic Pollutants (POPs)

Acid Deposition Monitoring Network in East Asia (EANET) - Acid deposition

Collaboration with World Radiation Centre, Davos, Switzerland - Aerosol Optical Depth monitoringusing Precision Filter Radiometer (PFR)

Southern Hemisphere Additional Ozonesondes (SHADOZ) Programme - Ozonesonde

European research project “SHIVA” (Stratospheric ozone: Halogen Impacts in a Varying Atmosphere)

Yayasan Sabah, University Malaysia Sabah, Lancaster University, University of Leicester, Universityof Cambridge, University of York, Leeds University, University of Manchester, University of EastAnglia, Centre for Ecology and Hydrology Edinburgh, Facility for Airborne Atmospheric Measurement& National Center for Atmospheric Research and Environmental Protection Agency - Oxidant andParticle Photochemical Processes Above a South-East Asian Tropical Rain Forest (OP3)

GREENHOUSE GASES MEASUREMENTSIt is known that one of the main contributors to the climate change are the long-lived GHG namely CO2, CH4, N2O and other lesser gases. MMD areaware of the importance in keeping the status of GHG concentration updated, such that an environmental sustainability development could be properlyplanned and structured. Among activities that MMD prioritized are the GHG monitoring and since 2004, MMD has collaborated with CommonwealthScientific and Industrial Research Organisation (CSIRO) in installing a LoFlo Mark II CO2 Analyzer at Danum Valley GAW station. At the same time MMDis also collaborated with NIES since 2010 to install the Flask Sampling system in Danum Valley.

The LoFlo Analyzer measure carbon dioxide (CO2) continuously, while flask air samples are collected once a week. In order to maintain the accuracy ofthe instrument, the LoFlo Analyzer is calibrated every 4 to 6 weeks. Figure 4 showed the hourly CO2 concentrations measured using LoFlo Analyzer andweekly average CO2 concentrations measured using Flask Sampling at Danum Valley GAW Station from June 2009 to June 2012. The hourly CO2

concentrations ranged from 385 to 400 ppm while the weekly concentrations ranged from 380 to 400 ppm. Figure 5 showed the trend of annual averageCO2 concentration for both Danum Valley and Mauna Loa are quite similar with both are showing an increasing trend of 1.86 ppm/year for Danum Valleyand 1.98 ppm/year for Mauna Loa.

Figure 4 Figure 5

REACTIVE GASES MEASUREMENTSCurrently, the Malaysian Meteorological Department continues to monitor gases such as sulphur dioxide (SO2) and nitrogen dioxide(NO2) at the Petaling Jaya and Cameron Highlands site using the passive samplers. In addition to passive samplers, the MalaysianMeteorological Department also monitors other gases and ions in the atmosphere at 3 GAW stations by using filter pack samplers.The 2011 average percentage of gases and ions of atmospheric dry deposition for the 3 stations using filter pack samplers is shownin Figure 6, whereby gases is the main contributor to the dry deposition compared to particulate ions.

The main gas found in the atmospheric dry deposition was ammonia (NH3) and Petaling Jaya has the highest concentration of NH3followed by Danum Valley and Cameron Highlands. Meanwhile, ammonium (NH4

+) is the main particulate ion found in theatmosphere with the highest concentration of NH4

+ was recorded in Cameron Highlands followed by Petaling Jaya and DanumValley.

PRECIPITATION CHEMISTRY MEASUREMENTSRain acidity is commonly reported in pH. pH is ameasure of the hydrogen ion concentration in aliquid and has a scale ranging from 0 to 14. Rainfrom even very clean, remote sites is slightly acidicwith pH varying between 5.2 to 6.0 due to thepresence of dissolved natural acids, therefore rain isonly considered acidic if the pH is less than 5.2.Since rainfall amount varies all the time, averagevalues of pH are volume weighted beforecomparisons between sites are made. MMD useseither the Acid Precipitation Sampler or the Wet-Only Sampler to collect rainwater in its network. Therainwater samples are accumulated weekly and abiocide, thymol is used to prevent biologicaldegradation of the samples. The samples are thensent to the Department of Chemistry’s laboratory forchemical analysis.

Figure 1

OZONE MEASUREMENTSSurface ozone in Danum Valley is measured using the THERMO 49i UV Ozone Analyzer. Surface ozone plays animportant role in physical, chemical and radiative process in the troposphere and also contributes to thegreenhouse effect. As shown in Figure 7, the daily average of ozone concentration recorded from July 2011 - June2012 are ranged from 2.8 - 20.1 ppb.

Daily total column ozone is monitored in Petaling Jaya using the Brewer Spectrophotometer. The measuredamount of total column ozone varied between 232 and 283 Dobson Unit (DU) in 2011 (Figure 8). There is aseasonal variation in ozone concentration but it is not as evident as those sites in the middle latitudes.

The vertical ozone profile is measured at Kuala Lumpur International Airport (KLIA), Sepang using ozonesondereleased at the beginning and middle of the month. The annual mean vertical ozone profile for 2011 is shown inFigure 9. The profile shows a minimum at about 14 kilometers (km) above mean sea level (MSL) corresponding tothe top of the tropical tropopause layer. Above 15 km, ozone level increase rapidly to a maximum at about 27.5kmabove MSL.

Figure 8Figure 7

Figure 9

AEROSOLS MEASUREMENTSAerosols are made up of a composite group of matter which could be liquids or solids suspended in the atmosphere ranging in size from less than onemicron to almost a hundred microns. The major part of the mass of aerosols is contributed by the larger particles. Measurement of atmospheric aerosolshave consistently shown that 90% of the particles by numbers are less than 0.1 micron in diameter while more than 90% of the mass is associated withparticles of diameters larger than 1 micron. Particles in the 0.1 to 5-10 micron range are very significant to the human health because they are ofrespirable size. Besides this effect, particles of these sizes can affect meteorological parameters such as visibility and solar radiation, and can be involvedin chemical reactions in the atmosphere producing secondary pollutants.

Particulate Matter of less than 10 micron (PM10) concentration was measured at 16 stations in the monitoring network using the High-Volume PM-10Sampler. The daily mean PM10 concentration in 2011 for Petaling Jaya and Cameron Highlands stations is shown in Figure 2 and Figure 3 respectively.At an elevation of about 1500 m above sea level in fairly clean environment, Cameron Highlands showed lower PM10 concentration as compared toPetaling Jaya station which is located in the urban area. Generally, the daily mean concentration of PM10 for Petaling Jaya and Cameron Highlandsstations was very much below 150.0 µg/m3 which is the recommended Malaysian Ambient Air Quality Guidelines.

Figure 2 Figure 3

Ozonesonde

PETALING JAYA CAMERON HIGHLANDS DANUM VALLEY

Figure 6

CSIRO - LoFlo Calibration

IFT Germany -Nephelometer Calibration

SHADOZ - Ozonesonde

EANET - Acid Deposition

NIES - Flask Sampling

EANET Participating Countries

The annual rainwater pH distribution map for the year 2000 to 2011 is shown in Figure 1, wherein the 2011, the state of Sabah and Sarawak received rainfall with pH between 5.2 and 5.6. InPeninsular, Perlis state recorded the least acidic rainfall with the pH values > 5.6 followed byKedah with pH values between 5.2 and 5.6. The most acidic rainfall has been recorded inSelangor with the pH values < 4.4 whereas other states of Peninsular received rainfall with pHbetween 4.4 and 5.2. The areas that experienced high levels of acidity are categorized as rapidgrowth centres, heavily industrialized with high population density.