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Abstract

Daily retrieved Ozone (O3) column data for 12 day for periods varying (11-18 August) 2005 and 2003 and (12-19 February) 2005, obtained from the Atmospheric Infrared Sounder AIRS, are utilized to investigate the ozone distribution over the Southeast Asia. Approach: AIRS included on the Earth Observing System (EOS) Aqua satellite launched on 4 May 2002. Ozone (O3) is the gas that naturally present in our atmosphere and is a critical atmospheric trace species in the stratosphere and troposphere. Most ozone resides in the stratosphere. Ozone can be “good” or “bad” for your health and the environment. Closer to Earth, in the air we breathe, Ozone is a harmful pollutant that causes damage to lung tissue and plants; it is a major constituent of smog. Results: The aim of this study was to investigate Daily Distribution map and Indonesia forest fires influences on O3 over Peninsular Malaysia and Thailand. The land use map of the study area was conducted by using total column O3 obtained from AIRS/Aqua Level 3 Daily (AIRX3STD) 1×1°spatial resolution ascending Standard, are used to study the O3 distribution and the impact of Indonesia forest fire. Considerable variations demonstrate annual changes in rainfall and drought patterns in various seasons (dry and wet season). Note such variations in the Ozone emissions over study area, while highest O3 occurs over Industrial, congested urban zones and existence of Swamps and lakes during dry season and a greater draw down of O3 occurs in the pristine marine environment over Surat Thani during wet seasons. Conclusion/Recommendations: In particular, we observe a quasi-biennial variation in O3 emissions from study area with two contrary cases, the higher concentrations around the equatorial regions at dry season and less at wet season. Examining satellite measurements, we find the enhanced O3 emission correlates with occasions of less rainfall during dry season.

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... The resulting increase of ultraviolet radiation at Earth's surface may cause high rates of skin cancer and eye cataracts because of the induction of chemical reactions between high energy photons with the exposed surfaces. In addition, excessive exposure to ultraviolet radiation can damage single-cell organisms, aquatic ecosystems, and terrestrial plant life [9]. Hence, ozone can be considered as a beneficial ultraviolet protection in the stratosphere but a harmful matter to human being at the ground level [10]. ...
... The instrument called a Dobson spectrophotometer, measures the intensity of sunlight at two wavelengths, where one Dobson Unit (DU) is defined as 0.01 mm thickness at standard temperature and pressure (STP). Ozone layer thickness is expressed as Dobson units, by measuring its physical thickness when compressed it in the Earth's atmosphere [9]. ...
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... The main component of GHG are carbon dioxide (CO 2 ), methane (CH 4 ) and carbon monoxide (CO), The main sources of GHG emission are burning of fossil fuels, solid waste degradation, biological respiration and agriculture soil. The study of GHGs has become a hot topic investigated by several researchers globally [1][2][3][4][5][6] , in surrounding countries [7][8][9] , and locally [7]. Carbon dioxide (CO 2 ) is most effective greenhouse gases in the atmosphere; it is the largest contributor among the global warming gases, where the increasing the concentration of carbon dioxide has a significant impact on climate change. ...
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The Carbon Dioxide (CO2) gas is one of the most important greenhouse gases that cause global warming. Investigation of increasing concentration of CO2 in global the atmosphere is the most pressing environmental concern of present and coming decades. The increasing of CO2 has a significant impact on climate change, the Climate change can only be controlled through a significant lowering in carbon dioxide emissions worldwide. CO2 emissions were studied in Iraq and period (2003-2016) and were used atmospheric Infrared sounder (AIRS) data, onboard NASA’s Aqua Satellite. In order to know the behavior of CO2 distribution in Iraq use analysis of trends in seven stations: Mosul, Sulaimaniyah, Rutba, Baghdad, Nukhayb, Nasiriyah and Basra). The average monthly and standard deviation was (389 ± 1.08 ppm) for the entire study period. The maximum values occur during April - May (391.4, 391.8 ppm) over Nukhayb and Rutba respectively, whereas the minimum values observed during September– October (387.1, 387 ppm) over Nasiriyah and Basra. Monthly distributions for CO2 show seasonal fluctuations between spring and autumn, the highest value of CO2 is in the spring and lowest in autumn for the entire study period. The increase was apparent from the trend analysis for entire of the period (2003-2016).
... Always people have contended with excessive heat, dust storms, shortage of rainfall and harsh geography across the Middle East area. During last century industrial development, climate change, political upheaval and war had left a legacy of environmental influences and health problems (Jasim et al., 2010). ...
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Observations of methane (CH4) retrieved from Atmospheric Infrared Sounder (AIRS) on the EOS/Aqua platform from 2003-2015 show a strong, plume-like enhancement of CH4 over central and southern-east parts of Iraq during August - September, with the maximum occurring in early September and minimum in March - May over western, southwest, and north-east regions. The percentage change differences results shows the highest differences occurred over the central and southern regions and the smallest differences occurred over the western and southwest regions. To better validate the retrieved data from AIRS three stations at different locations were chosen for trend analysis. The mean and standard deviation in Mosul, Baghdad and Basrah was (3.610 ± 0.042, 3.818 ± 0.048, 3.824 ± 0.055) x10 19 Mole.Cm -2 respectively for monthly long term trend analysis. Annual trend analysis shows positive trends, and ranged between (0.0083 and 0.0097) Mole.Cm -2 .y -1 for Mosul and Basrah, respectively. Monthly trend analysis have positive trends (0.0092) Mole.Cm -2 .y -1 for Mosul and (0.0107) Mole.Cm -2 .y -1 for Baghdad and Basrah. The annual linear growth rate were (2%) for Mosul, and (3%) for Baghdad and Basrah, and monthly linear growth rates were (5%) for Mosul and Baghdad, and (6%) for Basrah. Further daily long term trend shows significant linear increase of (3.7 %) caused a trend of (0.0107 × 10 19 ) Mole.Cm -2 .y -1 in Baghdad. The standard deviation of variation in daily average CH4 as a percentage deviation from the mean for the departure from the mean was (1.62%), (0.06×10 19 Mole.Cm -2 ). And the day to day variation with a clear seasonal change shows standard deviation of enter sequential changes was (0.053 × 10 19 ) Mole.Cm -2 . These results indicate that Satellite observations efficiently show the temporal variations of the CH4 values over different regions.
... Always people have contended with excessive heat, dust storms, shortage of rainfall and harsh geography across the Middle East area. During last century industrial development, climate change, political upheaval and war had left a legacy of environmental influences and health problems (Jasim et al., 2010). ...
Article
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Observations of methane (CH 4) retrieved from Atmospheric Infrared Sounder (AIRS) on the EOS/Aqua platform from 2003-2015 show a strong, plume-like enhancement of CH 4 over central and southern-east parts of Iraq during August-September, with the maximum occurring in early September and minimum in March-May over western, southwest, and northeast regions. The percentage change differences results shows the highest differences occurred over the central and southern regions and the smallest differences occurred over the western and southwest regions. To better validate the retrieved data from AIRS three stations at different locations were chosen for trend analysis. The mean and standard deviation in Mosul, Baghdad and Basrah was (3.610 ± 0.042, 3.818 ± 0.048, 3.824 ± 0.055) x10 19 Mole.Cm-2 respectively for monthly long term trend analysis. Annual trend analysis shows positive trends, and ranged between (0.0083 and 0.0097) Mole.Cm-2 .y-1 for Mosul and Basrah, respectively. Monthly trend analysis have positive trends (0.0092) Mole.Cm-2 .y-1 for Mosul and (0.0107) Mole.Cm-2 .y-1 for Baghdad and Basrah. The annual linear growth rate were (2%) for Mosul, and (3%) for Baghdad and Basrah, and monthly linear growth rates were (5%) for Mosul and Baghdad, and (6%) for Basrah. Further daily long term trend shows significant linear increase of (3.7 %) caused a trend of (0.0107 × 10 19) Mole.Cm-2 .y-1 in Baghdad. The standard deviation of variation in daily average CH4 as a percentage deviation from the mean for the departure from the mean was (1.62%), (0.06×10 19 Mole.Cm-2). And the day to day variation with a clear seasonal change shows standard deviation of enter sequential changes was (0.053 × 10 19) Mole.Cm-2. These results indicate that Satellite observations efficiently show the temporal variations of the CH 4 values over different regions.
... These diseases stem from the induction of chemical reactions between high-energy photons and exposed surfaces. In addition, excessive exposure to ultraviolet radiation can damage single-cell organisms, aquatic ecosystems, and terrestrial plant life (Jasim et al., 2010). Hence, the ozone can be considered as a form of beneficial ultraviolet protection in the stratosphere; however, it remains harmful to human beings at the ground level (Lu and Wang, 2006). ...
... The resulting increase of UV radiation at Earth's surface may cause high rates of skin cancer and eye cataracts because of the induction of chemical reactions between high energy photons with the exposed surfaces. In addition, excessive exposure to UV radiation can damage single-cell organisms, aquatic ecosystems, and terrestrial plant life [9]. Thus, stratosphere ozone is considered as good ozone because it absorbs UV-B from the sun. ...
Conference Paper
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Since few decades ago, air pollution has become a hot topic of environmental and atmospheric research due to the impact of air pollution on human health. Ozone is one of the important chemical constituent of the atmosphere, which plays a key role in atmospheric energy budget and chemistry, air quality and global change. Results from the analysis of the retrieved monthly data from Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY (SCIAMACHY) were utilized, in order to analyze the impact of air pollutants (CO2, CH4, H2O, and NO2) on the ozone in Peninsular Malaysia for 2003 using multiple regression analysis. SCIAMACHY onboard ENVISAT as part of the atmospheric chemistry payload of the third European Space Agency (ESA) Earth observation, is the first satellite instrument whose measurements is enough precise and sensitive for all the greenhouse gases to make observation at all atmospheric altitude levels down to the Earth's surface. Among the four pollutants, ozone was most affected by water vapor (H2O vapor), indicated by a strong beta coefficient (-0.769 - 0.997), depends on the seasonal variety. In addition, CO2 also shows a strong Beta coefficient (-0.654 - 0.717) and also affected by the seasonal variation. The variation of pollutants on the average explains change 50.1% of the ozone. This means that about 50.1% of the ozone is attributed to these pollutant gases. The SCIAMACHY data and the satellite measurements successfully identify the increase of the atmospheric air pollutants over the study area.
... Although ozone is colourless, it has distinct smell. Its presence near earth is tracked constantly for pollution monitoring [2]. Today, fixed and portable ozone sensor devices are commercially available for measurement of ozone. ...
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Accurate value of absorption cross section is required for correct measurement of ozone concentration. Measurement of ozone has been done at different altitude and pressure. However, previous work has failed to establish significant relation between pressure and ozone absorption cross section. Therefore, this work aims to establish relation between pressure and maximum ozone absorption cross section via spectralcalc.com gas cell simulator. Simulation results show maximum absorption cross section 1.148×10-21 m2 molecule-1 and maximum absorption wavelength 255.442 nm are independent of pressure changes from 0.1 atm to 3.0 atm. Thus, measurement of ozone concentration at maximum absorption wavelength is strongly recommended due to negligible pressure dependence.
... At troposphere, ozone is a pollutant that affects human health and environment [2]. Therefore, much work has been done to measure ozone concentration in the sky [3,4]. Besides, ozone is also generated on purpose for specific application. ...
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Ultraviolet absorption spectroscopy is reliable for ozone concentration measurement. Concentration range and optical path length are inversely related based on theoretical calculation and observation of previous work. However, gas cells for ozone application are typically not expandable. In addition, they incur cost for custom fabrication. Here we design a reconfigurable brass gas cell that may interchange optical path length between 5.6 cm and 10.8 cm. Components are available at low cost, easy to joint and ready to use. Theoretical background and gas cell structure are discussed. Practical transmittance values between e-0.65 and e-0.05 are proposed for theoretical calculation of concentration via Beer-Lambert law. The concentration values are used in SpectralCalc.com gas cell simulation to obtain transmittance. Both approaches yield comparable result. Simulation result shows concentration range of 5.6 cm optical path length gas cell (31.82 ppm to 413.67 ppm) is wider than concentration range of 10.8 cm optical path length gas cell (16.50 ppm to 214.49 ppm). Simulation condition is at transmittance from 0.5291 to 0.9522, sampling wavelength 253.65 nm, temperature 300 K and pressure 1 atm. Thus, we strongly recommend short optical path length gas cell (5.6 cm) for wide range of concentration measurement (31.82 ppm to 413.67 ppm).
... These diseases stem from the induction of chemical reactions between high-energy photons and exposed surfaces. In addition, excessive exposure to ultraviolet radiation can damage single-cell organisms, aquatic ecosystems, and terrestrial plant life (Jasim et al., 2010). Hence, the ozone can be considered as a form of beneficial ultraviolet protection in the stratosphere; however, it remains harmful to human beings at the ground level (Lu and Wang, 2006). ...
Article
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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, satellite remote sensing exhibits a very high spatial and temporal resolution. Variations of ozone concentrations in Peninsular Malaysia were observed and investigated by means of data retrieved from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). The aim of this study was to determine the monthly and seasonal ozone concentrations in Peninsular Malaysia from January 2003 to December 2009. We utilized total column ozone at level 2 of the WFMD version 1.0. A spatial resolution value of 1 degrees x1.25 degrees was used. Analysis indicated that the five selected sites exhibited strong seasonal atmospheric ozone concentration variations. These variations resulted from the significant differences between the northeast monsoon (NEM) and the southwest monsoon (SWM). As the NEM prevails, cold air breaks out from Siberia and spreads to the equatorial region in the form of northeasterly cold surge winds. These winds manifest in low-level anticyclones over Southeast Asia. Inversely, the air masses from the southwest contribute to long-range air pollution. During SWM, the transport of atmospheric ozone by wind is associated with biomass burning in Sumatra, Indonesia. HYSPLIT was also utilized to identify the air pollutant transport between NEM and SWM toward Peninsular Malaysia. Comparisons were made between the ozone data from five sites in 2009. Data were retrieved from SCIAMACHY and the Atmospheric Infrared Sounder (AIRS). The relative difference average of the ozone data measured by SCIAMACHY and AIRS was approximately 6%.
... The Dobson spectrophotometer measures the intensity of sunlight at two wavelengths; one Dobson unit is defined as 0.01 mm thickness at standard temperature and pressure. The thickness of the ozone layer is expressed in Dobson units and is measured when the layer is compressed in the earth's atmosphere (Jasim et al. 2010). ...
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This study aimed to predict monthly columnar ozone (O3) in Peninsular Malaysia by using data on the concentration of environmental pollutants. Data (2003-2008) on five atmospheric pollutant gases (CO2, O3, CH4, NO2, and H2O vapor) retrieved from the satellite Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) were employed to develop a model that predicts columnar ozone through multiple linear regression. In the entire period, the pollutants were highly correlated (R = 0.811 for the southwest monsoon, R = 0.803 for the northeast monsoon) with predicted columnar ozone. The results of the validation of columnar ozone with column ozone from SCIAMACHY showed a high correlation coefficient (R = 0.752-0.802), indicating the model's accuracy and efficiency. Statistical analysis was utilized to determine the effects of each atmospheric pollutant on columnar ozone. A model that can retrieve columnar ozone in Peninsular Malaysia was developed to provide air quality information. These results are encouraging and accurate and can be used in early warning of the population to comply with air quality standards.
... The resulting increase of ultraviolet radiation at Earth's surface may cause high rates of skin cancer and eye cataracts because of the induction of chemical reactions between high energy photons with the exposed surfaces. In addition, excessive exposure to ultraviolet radiation can damage single-cell organisms, aquatic ecosystems, and terrestrial plant life [13]. Hence, ozone can be considered as a beneficial ultraviolet protection in the stratosphere but a harmful matter to human being at the ground level [14]. ...
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Increasing of atmospheric ozone concentrations have received great attention around the whole because of its characteristic, in order to degrade air quality and brings hazard to human health and ecosystems. Ozone, one of the most pollutants source and brings a variety of adverse effects on plant life and human being. Continuous monitoring on ozone concentrations at atmosphere provide information and precautions for the high ozone level, which we need to be established. Satellite observation of ozone has been identified that it can provide the precise and accurate data globally, which sensitive to the small regional biases. We present measurements from Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) included on the European environmental satellite ENVISAT, launched on 1st of March 2002. Main objective of this study is to examine the ozone distribution over Peninsular Malaysia using SCIAMACHY level-2 of total ozone column WFMD version 1.0 with spatial resolution 1° x 1.25°. Maps of time averaged (yearly, tri-monthly) ozone was generated and analyzed over Peninsular Malaysia for the year 2003 using PCI Geomatica 10.3 image processing software. It was retrieved using the interpolation technique. The concentration changes within boundary layer at all altitude levels are equally sensitive through the SCIAMACHY nearinfrared nadir observations. Hence, we can make observation of ozone at surface source region. The results successfully identify the area with highest and lowest concentration of ozone at Peninsular Malaysia using SCIAMACHY data. Therefore, the study is suitable to examine the distribution of ozone at tropical region.
... Photochemical oxidants are trace species, which are formed during the atmospheric photo-oxidation of a variety of trace gases (Kley et al., 1998; Rajab et al., 2010). Ozone, one of the most important photo-oxidants in the urban environment, originates from the in-situ photochemical production in the reactions of its precursors (NOx, CO, VOCs) and from vertical and horizontal transport (Minoura 1999; Latha and Badarinath, 2004; Badarinath et al., 2007; Lin et al., 2008; Ahmad et al., 2010). ...
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Problem statement: Variations of ozone (O 3) concentrations in the Eastern Coastal Region of the Malaysia peninsula were investigated using data obtained from the Malaysian Department of the Environment. The aim of this study was to determine the monthly and seasonal variations of ozone concentrations at all monitoring sites. This study deals with the air quality data recorded at four air quality monitoring stations in the East Coast of the Malaysian peninsula over a ten year period (1997- 2006). Approach: We focused on the usage of S-Plus and SPSS to analyze this data. The S-Plus programming was used to impute missing data and SPSS was used to obtain the variations of ozone and also to clarify the relationship between stations. Results: Over the entire 10 year period (1997- 2006), the trend in annual baseline ozone generally increased each year for all the four monitoring sites. There was also a seasonal variability in the measured ozone levels with high concentrations during the southwest monsoon and the northeast monsoon season, producing a significant increase in the amplitude of the seasonal cycle. The results also shown that the highest ozone concentrations were recorded at the Bukit Kuang air monitoring station (S1), with a daily mean value of 19 ppb followed by the Indera Mahkota air monitoring station (S2). The concentration of ozone recorded at Kota Bharu (S3) and Kuala Terengganu (S4), two stations located in the city centre, was found to be lower than the values recorded at Bukit Kuang and Indera Mahkota. The correlation between O 3 and NO is high at Kuala Terengganu (S4) (ρ = -0.579), whilst the relationship between O 3 and NO 2 are high (ρ = -0.397) at Indera Mahkota (S2). Conclusion: The concentration of ozone in the East Coast of Malaysian peninsula depends on the concentration of NOx and seasonal meteorological factors.
... μm and 8.8-15.4 μm infrared wavebands at a nominal spectral resolution, also includes four visible/near-IR (Vis/NIR) channels between 0.40 and 0.94 μm, with a 2.3-km FOV (Rajab et al., 2010). ...
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Methane (CH4) is a significant greenhouse gas (GHG's) with a relatively short atmospheric lifetime of about 12 years, and is released to the atmosphere by biological processes occurring in anaerobic environments. The CH4 is second in importance only to CO2 with regard to its environmental effects, and its relative global warming ability is 23 times that of CO2 over a time horizon of 100 years. The interannual distribution of atmospheric CH4 has been studied in Peninsular Malaysia during the period 2003–2009 using Atmosphere Infrared Sounder (AIRS) data, onboard NASA's Aqua Satellite. The analysis of CH4 above five dispersed stations in the study area shows that the high CH4 growth rates observed at the end of each year can be attributed to the increased emissions from biomass burning and wetlands, and the reduced hydroxyl (OH) sink. In particular, we observe a quasi-biennial variation in CH4 emissions in Peninsular Malaysia, with varying magnitudes in peak emissions occurring in 2004, 2006, and 2008. The seasonal variation in the CH4 fluctuated significantly between northeast (NEM) and southwest (SWM) monsoon seasons. The CH4 value in the NEM season was higher than in the SWM season, and higher in the north regions, above the latitude 4°, than in the rest of area throughout the year. To study the CH4 distribution over peninsular Malaysia for 2009, monthly CH4 maps were generated using the Kriging interpolation technique. The AIRS data and satellite measurements are able to measure the increase in the atmospheric CH4 concentrations over different regions.
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The Atmospheric Infrared Sounder (AIRS) and its two companion microwave sounders, AMSU and HSB were launched into polar orbit onboard the NASA Aqua Satellite in May 2002. NASA required the sounding system to provide high-quality research data for climate studies and to meet NOAA's requirements for improving operational weather forecasting. The NOAA requirement translated into global retrieval of temperature and humidity profiles with accuracies approaching those of radiosondes. AIRS also provides new measurements of several greenhouse gases, such as CO2, CO, CH4, O3, SO2, and aerosols.The assimilation of AIRS data into operational weather forecasting has already demonstrated significant improvements in global forecast skill. At NOAA/NCEP, the improvement in the forecast skill achieved at 6 days is equivalent to gaining an extension of forecast capability of six hours. This improvement is quite significant when compared to other forecast improvements over the last decade. In addition to NCEP, ECMWF and the Met Office have also reported positive forecast impacts due AIRS.AIRS is a hyperspectral sounder with 2,378 infrared channels between 3.7 and 15.4 µm. NOAA/NESDIS routinely distributes AIRS data within 3 hours to NWP centers around the world. The AIRS design represents a breakthrough in infrared space instrumentation with measurement stability and accuracies far surpassing any current research or operational sounder. The results we describe in this paper are ``work in progress,'' and although significant accomplishments have already been made much more work remains in order to realize the full potential of this suite of instruments.
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The Atmospheric Infrared Sounder (AIRS), the Advanced Microwave Sounding Unit (AMSU), and the Humidity Sounder for Brazil (HSB) form an integrated cross-track scanning temperature and humidity sounding system on the Aqua satellite of the Earth Observing System (EOS). AIRS is an infrared spectrometer/radiometer that covers the 3.7-15.4-μm spectral range with 2378 spectral channels. AMSU is a 15-channel microwave radiometer operating between 23 and 89 GHz. HSB is a four-channel microwave radiometer that makes measurements between 150 and 190 GHz. In addition to supporting the National Aeronautics and Space Administration's interest in process study and climate research, AIRS is the first hyperspectral infrared radiometer designed to support the operational requirements for medium-range weather forecasting of the National Ocean and Atmospheric Administration's National Centers for Environmental Prediction (NCEP) and other numerical weather forecasting centers. AIRS, together with the AMSU and HSB microwave radiometers, will achieve global retrieval accuracy of better than 1 K in the lower troposphere under clear and partly cloudy conditions. This paper presents an overview of the science objectives, AIRS/AMSU/HSB data products, retrieval algorithms, and the ground-data processing concepts. The EOS Aqua was launched on May 4, 2002 from Vandenberg AFB, CA, into a 705-km-high, sun-synchronous orbit. Based on the excellent radiometric and spectral performance demonstrated by AIRS during prelaunch testing, which has by now been verified during on-orbit testing, we expect the assimilation of AIRS data into the numerical weather forecast to result in significant forecast range and reliability improvements.
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The NASA Atmospheric InfraRed Sounder (AIRS) is a new generation of meteorological advanced sounders for operational and research use. All channels for all fields of view from the AIRS were processed into operational binary universal form for the representation (BUFR) of meteorological data format. AIRS data for January 2004 were BUFR-ized and passed to an enhanced operational analysis in current operational format. The verification statistics were derived using the National Centers for Environmental Prediction (NCEP) operational verification scheme. AIRS hyperspectral data shows significant positive impact in forecast skill over both the Northern and Southern Hemisphere for January 2004.
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An exceptional rainstorm affected the eastern coast of Peninsular Malaysia during 9–11 December 2004 as a result of a westward propagating tropical disturbance known as the Borneo vortex. Rainfall totals near the storm center exceeded 600 mm and led to flash floods, loss of life and severe damage in the area. This study presents the results of a numerical simulation of this event using the fifth generation of the Penn State – NCAR Mesoscale Model (MM5). The model successfully simulated the synoptic circulation and reproduced the episode with comparable spatial patterns and total accumulated amount of precipitation to the observed. Various sensitivity experiments showed that the local topography is decisive in shaping the rainfall distribution during the storm episode. The role of the terrain elevation appears to be to block the westward progression of the system and inhibit excessive rainfall in the inland areas of Peninsular Malaysia. To the north of the storm center where coastal terrain elevation is relatively high, orography plays an important role in the rainfall by providing an additional forcing for moist air lifting. An additional fake dry simulation suggested that latent heat release is crucial for the development of the storm. Without latent heating, the vertical coupling of low-level convergence and upper level divergence is weakened and the vertical motion associated with the storm is suppressed.
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Forest and land fires in Southeast Asia have many social, economic, and environmental impacts. Tropical peatland fires affect global carbon dynamics, and haze from peat fires has serious negative impacts on the regional economy and human health. To mitigate these fire-related problems, forest and land management agencies require an early warning system to assist them in implementing fire prevention and management plans before fire problems begin. Fire Danger Rating Systems (FDRS) were developed for Indonesia and Malaysia to provide early warning of the potential for serious fire and haze events. In particular, they identify time periods when fires can readily start and spread to become uncontrolled fires and time periods when smoke from smouldering fires will cause an unacceptably high level of haze. The FDRS were developed by adapting components of the Canadian Forest Fire Danger Rating System, including the Canadian Forest Fire Weather Index (FWI) System and the Canadian Forest Fire Behavior Prediction (FBP) System, to local vegetation, climate, and fire regime conditions. A smoke potential indicator was developed using the Drought Code (DC) of the FWI System. Historical air quality analysis showed that the occurrence of severe haze events increased substantially when DC was above 400. An ignition potential indicator was developed using the Fine Fuel Moisture Code (FFMC) of the FWI System. Historical hot spot analysis, grass moisture, and grass ignition studies showed that fire occurrence and the ability for grass fires to start and spread dramatically increased when FFMC > 82. The Initial Spread Index (ISI) of the FWI System was used to develop a difficulty of control indicator for grassland fires, a fuel type that can exhibit high rates of spread and fire intensity. This ISI-based indicator was developed using the grass fuel model of the FBP System, along with a standard grass fuel load and curing level estimated from previous Indonesian studies. Very high fire intensity is expected in grasslands when ISI ≥ 6. To provide early warning, the FDRS identifies classes of increasing fire danger as the FFMC, DC, and ISI approach these key threshold values. The Indonesian FDRS is now operated nationally at the Indonesian Meteorological and Geophysical Agency. The Malaysian Meteorological Service operates the Malaysian FDRS and displays regional outputs for the Association of Southeast Asian Nations. The FDRS are being used by forestry, agriculture, environment, and fire and rescue agencies to develop and implement fire prevention, detection, and suppression plans.
http://daac.gsfc.nasa.gov/AIRS/documentation Intraseasonal variations of the tropical total ozone and their connection to the madden-Julian oscillation
  • E T Olsen
  • E Fishbein
  • S Granger
  • S Y Lee
  • E Manning
Olsen, E.T., E. Fishbein, S. Granger, S.Y. Lee and E. Manning et al., 2005. AIRS/AMSU/HSB Version 5 Data Release User Guide. http://daac.gsfc.nasa.gov/AIRS/documentation/v4_ docs/V4_Data_Release_UG.pdf Stephen, W.B., 2005. Discovery's Test Mission a Success. National Aeronautics and Space Administration, (NASA). http://www.nasa.gov/returntoflight/main/index.html Tian, B., Y.L. Yung, D.E. Waliser, T. Tyranowski and L. Kuai et al., 2007. Intraseasonal variations of the tropical total ozone and their connection to the madden-Julian oscillation. Geophys. Res. Lett., 34: L08704. DOI: 10.1029/2007GL029451
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  • W W Mcmillan
  • C Barnet
  • L Strow
  • M T Chahine
  • M L Mccourt
McMillan, W.W., C. Barnet, L. Strow, M.T. Chahine and M.L. McCourt et al., 2005. Daily global maps of carbon monoxide from NASA's atmospheric infrared sounder. Geophys. Res. Lett., 32: L11801. DOI: 10.1029/2004GL021821 Morris, A.G., S. Hersey, M.A. Thompson, S. Pawson and E.J. Nielsen et al., 2006. Alaskan and Canadian forest fires exacerbate ozone pollution over Houston, Texas, on 19 and 20 July 2004. J. Geophys. Res., 111: D24S03.1-D24S03. http://cat.inist.fr/?aModele=afficheN&cpsidt=1847
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  • J Bian
  • A Gettelman
  • H Chen
  • L Pan
Bian, J., A. Gettelman, H. Chen and L. Pan, 2007. Validation of satellite ozone profile retrievals using Beijing ozonesonde data. J. Geophys. Res., 112: D06305. DOI: 10.1029/2006JD007502 Chahine, M.T., S.P. Thomas, H.A. Hartmut, A. Robert and B. Christopher et al., 2006. The Atmospheric Infrared Sounder (AIRS): Improving weather forecasting and providing new data on greenhouse gases. Am. Meteorolog. Soc., 87: 911-926.
Twenty Questions and Answers about the Ozone Layer: 2006 update. World Meteorological Organization, Geneva, Scientific Assessment of Ozone Depletion Ozone matters
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Fahey, D.W., 2007. Twenty Questions and Answers about the Ozone Layer: 2006 update. World Meteorological Organization, Geneva, Scientific Assessment of Ozone Depletion. http://www.unep.ch/ozone/Assessment_Panels/SA P/Scientific_Assessment_2006/Twenty_Questions. pdf Hoskins, A.J., 2001. Ozone matters. Indoor Built Environ., 10: 1-2.
Trace gas measurements from infrared satellite for chemistry and climate applications
  • C Clerbaux
  • J Hadgi-Lazaro
  • S Turquety
  • G Metie
  • F P Coheur
Clerbaux, C., J. Hadgi-Lazaro, S. Turquety, G. Metie and F.P. Coheur, 2003. Trace gas measurements from infrared satellite for chemistry and climate applications. Atmosph. Chem. Phys., 3: 1495-1508.
Twenty Questions and Answers about the Ozone Layer
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Numerical case study of an extreme rainfall event during 9-11
  • L Juneng
  • F T Tangang
  • C J C Reason
Juneng, L., F.T. Tangang and C.J.C. Reason, 2007. Numerical case study of an extreme rainfall event during 9-11 December 2004 over the east coast of Peninsular Malaysia. Meteorol. Atmosph. Phys., 98: 81-98.
AIRS/AMSU/HSB Version 5 Data Release User Guide
  • E T Olsen
  • E Fishbein
  • S Granger
  • S Y Lee
  • E Manning
Olsen, E.T., E. Fishbein, S. Granger, S.Y. Lee and E. Manning et al., 2005. AIRS/AMSU/HSB Version 5 Data Release User Guide. http://daac.gsfc.nasa.gov/AIRS/documentation/v4_ docs/V4_Data_Release_UG.pdf
Discovery's Test Mission a Success. National Aeronautics and Space Administration
  • W B Stephen
Stephen, W.B., 2005. Discovery's Test Mission a Success. National Aeronautics and Space Administration, (NASA).