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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS1981

Westward propagating predecessors of monsoon depressions

Sea-level pressure data for the period 1969-1978 are used to investigate the relation between Bay of Bengal lows and depressions and disturbances propagating from the east. Of the 52 lows and depressions studied, 45 were associated with such predecessor disturbances. In 12 cases, the predecessor was associated with a typhoon or named tropical storm in the South China Sea, while the remaining 33 were weaker systems originating over a broad region of land and sea. From examination of time sections over the same period from eastern Thailand to the Burmese coast, 50 westward-moving disturbances with considerable vertical extent were identified, 64% of which developed into lows or depressions on reaching the Bay. In 60% of the 50 instances, the disturbance could be traced to the South China Sea (32% typhoons and 28% weaker circulations). The remaining 40% of the 50 disturbances appeared to originate over land.

Saha, K.↗
NASA NTRS1992

Mechanism of Muong Nong-type tektite formation and speculation on the source of Australasian tektites

The source crater of the youngest and largest of the tektite strewnfields, the Australasian strewnfield, has not been located. A number of lines of evidence indicate that the Muong Nong-type tektites, primarily found in Indochina, are more primitive than the much more abundant and widespread splash-form tektites, and are proximal to the source. In this study the spatial distribution of Muong Nong-type tektite sites and chemical character have been used to indicate the approximate location of the source. The variation of Muong Nong-type tektite chemical composition appears to be caused by mixing of two silicate rock end-members and a small amount of limestone, and not by vapor fractionation. The variation in composition is not random, and does not support in situ melting or multiple impact theories. The distribution of both Muong Nong and splash-form tektite sites suggest the source is in a limited area near the southern part of the Thailand-Laos border.

Schnetzler, C. C.↗
NASA NTRS1992

Search for the 700,000-year-old source crater of the Australasian tektite strewn field

Many tektite investigations have hypothesized that the impact crater that was the source of the extensive Australasian strewn field lies somewhere in or near Indochina. This is due to variations in abundance and size of tektites across the strewn field, variation of thickness of microtektite layers in ocean cores, nature and ablation characteristics across the field, and, above all, the occurrence of the large, blocky, layered Muong Nong-type tektites in Indochina. A recent study of the location and chemistry of Muong Nong-type and splash-form tektites suggests that the source region can be further narrowed to a limited area in eastern Thailand and southern Loas. Satellite multispectral imagery, a digital elevation dataset, and maps showing drainage patterns were used to search within this area for possible anomalous features that may be large degraded impact craters. Four interesting structures were identified from these datasets, and they are presented.

Schnetzler, C. C.↗
NASA NTRS1992

Research relative to weather radar measurement techniques

This grant provides for some investigations related to weather radar measurement techniques applicable to meteorological radar systems in Thailand. Quality data are needed from those systems to support TRMM and other scientific investigations. Activities carried out during a trip to the radar facilities at Phuket are described.

Smith, Paul L.↗
NASA NTRS1995

Shuttle Earth Views, 1994

In this third part of a four-part video compilation of Space Shuttle Earth views, various geographical areas are shown, including both land and water masses. The views cover South America, Asia (North Vietnam, Laos, Cambodia, China, Malaysia, Thailand, Java, various islands, Burma, Philippines, Taiwan, Guam), New Guinea, Australia, Morocco, Southern Europe (Spain, Portugal, Algeria, Italy, Sicily, Greece, Former Republic of Yugoslavia, Tunisia), and parts of the Middle East (Libya, Saudi Arabia, Egypt, Israel, Jordan, Sinai, Cyprus, Lebanon, Iraq), the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, and the Mediterranean, Dead, Coral, Tyrrhenian, Adriatic, Ionian, Red, South China, Mindanao, Arafura, Sulu, Java, and China Seas. Each film clip has a heading that names the shuttle and the geographical location of the footage.

Source record↗
NASA NTRS2001

Controlling Malaria and Other Diseases Using Remote Sensing

Remote sensing offers the vantage of monitoring a vast area of the Earth continuously. Once developed and launched, a satellite gives years of service in collecting data from the land, the oceans, and the atmosphere. Since the 1980s, attempts have been made to relate disease occurrence with remotely sensed environmental and geophysical parameters, using data from Landsat, SPOT, AVHRR, and other satellites. With higher spatial resolution, the recent satellite sensors provide a new outlook for disease control. At sub-meter to I 10m resolution, surface types associated with disease carriers can be identified more accurately. The Ikonos panchromatic sensor with I m resolution, and the Advanced Land Imager with 1 Om resolution on the newly launched Earth Observing-1, both have displayed remarkable mapping capabilities. In addition, an entire array of geophysical parameters can now be measured or inferred from various satellites. Airborne remote sensing, with less concerns on instrument weight, size, and power consumption, also offers a low-cost alternative for regional applications. NASA/GSFC began to collaborate with the Mahidol University on malaria and filariasis control using remote sensing in late 2000. The objectives are: (1) To map the breeding sites for the major vector species; (2) To identify the potential sites for larvicide and insecticide applications; (3) To explore the linkage of vector population and transmission intensity to environmental variables; (4) To monitor the impact of climate change and human activities on vector population and transmission; and (5) To develop a predictive model for disease distribution. Field studies are being conducted in several provinces in Thailand. Data analyses will soon begin. Malaria data in South Korea are being used as surrogates for developing classification techniques. GIS has been shown to be invaluable in making the voluminous remote sensing data more readily understandable. It will be used throughout this study to clearly demonstrate the spatial relationship between the disease intensities, geophysical variables, and socioeconomic parameters. Asides from malaria and filariasis, application of remote sensing to the control of other diseases have been vigorously pursued by NASA's Environment and Health Initiative. The current program includes projects on Rift Valley fever, St. Louis encephalitis, dengue fever, ebola, African dust and diseases, meningitis, asthma, bartonellosis, cholera, and urban health concerns. Results from these projects indicate that remote sensing will play an increasingly important role in disease control in the future.

Kiang, Richard K.↗
NASA NTRS2000

Lidar Remote Sensing for Industry and Environment Monitoring

Contents include the following: 1. Keynote paper: Overview of lidar technology for industrial and environmental monitoring in Japan. 2. lidar technology I: NASA's future active remote sensing mission for earth science. Geometrical detector consideration s in laser sensing application (invited paper). 3. Lidar technology II: High-power femtosecond light strings as novel atmospheric probes (invited paper). Design of a compact high-sensitivity aerosol profiling lidar. 4. Lasers for lidars: High-energy 2 microns laser for multiple lidar applications. New submount requirement of conductively cooled laser diodes for lidar applications. 5. Tropospheric aerosols and clouds I: Lidar monitoring of clouds and aerosols at the facility for atmospheric remote sensing (invited paper). Measurement of asian dust by using multiwavelength lidar. Global monitoring of clouds and aerosols using a network of micropulse lidar systems. 6. Troposphere aerosols and clouds II: Scanning lidar measurements of marine aerosol fields at a coastal site in Hawaii. 7. Tropospheric aerosols and clouds III: Formation of ice cloud from asian dust particles in the upper troposphere. Atmospheric boundary layer observation by ground-based lidar at KMITL, Thailand (13 deg N, 100 deg. E). 8. Boundary layer, urban pollution: Studies of the spatial correlation between urban aerosols and local traffic congestion using a slant angle scanning on the research vessel Mirai. 9. Middle atmosphere: Lidar-observed arctic PSC's over Svalbard (invited paper). Sodium temperature lidar measurements of the mesopause region over Syowa Station. 10. Differential absorption lidar (dIAL) and DOAS: Airborne UV DIAL measurements of ozone and aerosols (invited paper). Measurement of water vapor, surface ozone, and ethylene using differential absorption lidar. 12. Space lidar I: Lightweight lidar telescopes for space applications (invited paper). Coherent lidar development for Doppler wind measurement from the International Space Station. 13. Space lidar II: Using coherent Doppler lidar to estimate river discharge. 14. Poster session: Lidar technology, optics for lidar. Laser for lidar. Middle atmosphere observations. Tropospheric observations (aerosols, clouds). Boundary layer, urban pollution. Differential absorption lidar. Doppler lidar. and Space lidar.

Singh, Upendra N.↗
NASA NTRS2004

Cloud-Aerosol Interaction and Its Impact on the Onset of the East Asian Summer Monsoon

Effect of aerosols from biomass burning on the early development of East Asian monsoon is investigated using various satellites and in situ observations including TOMS Aerosol Index (AI). GPCP precipitation, ISCCP cloud cover, and GISS surface air temperature. Based on TRMM fire produce and mean winds fields at 85Omb. we identified the source and interaction regions of aerosols and investigated aerosol-cloud-precipitation characteristics in those regions. During March-April, northern Thailand, Myanmar. and Laos are major source of smoke from the combustion of agricultural waste. Excessive smoke. represented by high AI, is observed especially during dry and cloud-free year. On the other hand. there is no ground source of smoke in the interaction region. The most of aerosols in this area are believed to be transported from the source region. AI is appeared to be correlated with more clouds and less precipitation in interaction region. It suggests that the aerosol-cloud interaction can alter the distribution of cloud and the characteristics of regional hydrology. Aerosol-induced changes in atmospheric stability and associated circulation turns out to be very important to pre-monsoon rainfall pattern in southern China. Prolonged biomass burning is especially effective in changing rainfall pattern during April and May. Results suggest that excessive aerosol transported from source region may intensify pre-monsoon rain band over central China in May and lead to early monsoon onset.

Kim, Kyu-Myong↗
NASA NTRS2005

Assessing Malaria Risks in Greater Mekong Subregion based on Environmental Parameters

At 4,200 km, the Mekong River is the tenth longest river in the world. It directly and indirectly influences the lives of hundreds of millions of inhabitants in its basin. The riparian countries - Thailand, Myanmar, Cambodia, Laos, Vietnam, and a small part of China - form the Greater Mekong Subregion (GMS). This geographical region has the misfortune of being the world's epicenter of falciparum malaria, which is the most severe form of malaria caused by Plasmodium falciparum. Depending on the country, approximately 50 to 90% of all malaria cases are due to this species. In the Malaria Modeling and Surveillance Project, we have been developing techniques to enhance public health s decision capability for malaria risk assessments and controls. The main objectives are: 1) identifying the potential breeding sites for major vector species; 2) implementing a malaria transmission model to identify the key factors that sustain or intensify malaria transmission; and 3) implementing a risk algorithm to predict the occurrence of malaria and its transmission intensity. The potential benefits are: 1) increased warning time for public health organizations to respond to malaria outbreaks; 2) optimized utilization of pesticide and chemoprophylaxis; 3) reduced likelihood of pesticide and drug resistance; and 4) reduced damage to environment. Environmental parameters important to malaria transmission include temperature, relative humidity, precipitation, and vegetation conditions. The NASA Earth science data sets that have been used for malaria surveillance and risk assessment include AVHRR Pathfinder, TRMM, MODIS, NSIPP, and SIESIP. Hindcastings based on these environmental parameters have shown good agreement to epidemiological records. Socioeconomic factors that may influence malaria transmissions will also be incorporated into the predictive models.

Kiang, Richard↗
NASA NTRS2005

Malaria Modeling and Surveillance for the Greater Mekong Subregion

At 4,200 km, the Mekong River is the tenth longest river in the world. It directly and indirectly influences the lives of hundreds of millions of inhabitants in its basin. The riparian countries - Thailand, Myanmar, Cambodia, Laos, Vietnam, and a small part of China - form the Greater Mekong Subregion (GMS). This geographical region has the misfortune of being the world's epicenter of falciparum malaria, which is the most severe form of malaria caused by Plasmodium falciparum. Depending on the country, approximately 50 to 90% of all malaria cases are due to this species. In the Malaria Modeling and Surveillance Project, we have been developing techniques to enhance public health's decision capability for malaria risk assessments and controls. The main objectives are: 1) Identifying the potential breeding sites for major vector species; 2) Implementing a malaria transmission model to identify the key factors that sustain or intensify malaria transmission; and 3) Implementing a risk algorithm to predict the occurrence of malaria and its transmission intensity. The potential benefits are: 1) Increased warning time for public health organizations to respond to malaria outbreaks; 2) Optimized utilization of pesticide and chemoprophylaxis; 3) Reduced likelihood of pesticide and drug resistance; and 4) Reduced damage to environment. Environmental parameters important to malaria transmission include temperature, relative humidity, precipitation, and vegetation conditions. These parameters are extracted from NASA Earth science data sets. Hindcastings based on these environmental parameters have shown good agreement to epidemiological records.

Kiang, Richard↗
NASA NTRS2007

Characterizing Aerosols over Southeast Asia using the AERONET Data Synergy Tool

Biomass burning, urban pollution and dust aerosols have significant impacts on the radiative forcing of the atmosphere over Asia. In order to better quanti@ these aerosol characteristics, the Aerosol Robotic Network (AERONET) has established over 200 sites worldwide with an emphasis in recent years on the Asian continent - specifically Southeast Asia. A total of approximately 15 AERONET sun photometer instruments have been deployed to China, India, Pakistan, Thailand, and Vietnam. Sun photometer spectral aerosol optical depth measurements as well as microphysical and optical aerosol retrievals over Southeast Asia will be analyzed and discussed with supporting ground-based instrument, satellite, and model data sets, which are freely available via the AERONET Data Synergy tool at the AERONET web site (http://aeronet.gsfc.nasa.gov). This web-based data tool provides access to groundbased (AERONET and MPLNET), satellite (MODIS, SeaWiFS, TOMS, and OMI) and model (GOCART and back trajectory analyses) databases via one web portal. Future development of the AERONET Data Synergy Tool will include the expansion of current data sets as well as the implementation of other Earth Science data sets pertinent to advancing aerosol research.

Giles, David M.↗
NASA NTRS2007

Surveillance and Control of Malaria Transmission Using Remotely Sensed Meteorological and Environmental Parameters

Meteorological and environmental parameters important to malaria transmission include temperature, relative humidity, precipitation, and vegetation conditions. These parameters can most conveniently be obtained using remote sensing. Selected provinces and districts in Thailand and Indonesia are used to illustrate how remotely sensed meteorological and environmental parameters may enhance the capabilities for malaria surveillance and control. Hindcastings based on these environmental parameters have shown good agreement to epidemiological records.

Kiang, R.↗
NASA NTRS2008

Accessing and Utilizing Remote Sensing Data for Vectorborne Infectious Diseases Surveillance and Modeling

Background: The transmission of vectorborne infectious diseases is often influenced by environmental, meteorological and climatic parameters, because the vector life cycle depends on these factors. For example, the geophysical parameters relevant to malaria transmission include precipitation, surface temperature, humidity, elevation, and vegetation type. Because these parameters are routinely measured by satellites, remote sensing is an important technological tool for predicting, preventing, and containing a number of vectorborne infectious diseases, such as malaria, dengue, West Nile virus, etc. Methods: A variety of NASA remote sensing data can be used for modeling vectorborne infectious disease transmission. We will discuss both the well known and less known remote sensing data, including Landsat, AVHRR (Advanced Very High Resolution Radiometer), MODIS (Moderate Resolution Imaging Spectroradiometer), TRMM (Tropical Rainfall Measuring Mission), ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer), EO-1 (Earth Observing One) ALI (Advanced Land Imager), and SIESIP (Seasonal to Interannual Earth Science Information Partner) dataset. Giovanni is a Web-based application developed by the NASA Goddard Earth Sciences Data and Information Services Center. It provides a simple and intuitive way to visualize, analyze, and access vast amounts of Earth science remote sensing data. After remote sensing data is obtained, a variety of techniques, including generalized linear models and artificial intelligence oriented methods, t 3 can be used to model the dependency of disease transmission on these parameters. Results: The processes of accessing, visualizing and utilizing precipitation data using Giovanni, and acquiring other data at additional websites are illustrated. Malaria incidence time series for some parts of Thailand and Indonesia are used to demonstrate that malaria incidences are reasonably well modeled with generalized linear models and artificial intelligence based techniques. Conclusions: Remote sensing data relevant to the transmission of vectorborne infectious diseases can be conveniently accessed at NASA and some other websites. These data are useful for vectorborne infectious disease surveillance and modeling.

Kiang, Richard↗
NASA NTRS2007

Continental Scale Aerosol Optical Properties Over East Asia as Measured by Aeronet and Comparison to Satellite and Modeled Results

The AERONET program has operated in E. Asia since 1995 providing time continuous and time averaged ground-based column-integrated aerosol optical properties in a variety of aerosol regimes In the last four years the distribution has greatly increased in Siberia, China, SE Asia and India in particular. Commensurate with that, significant improvement in data processing algorithms (Version 2.0) and access to ancillary data products through the WWW have become available to the scientific community. At this writing the following distribution represents E and S. Asia: 5 sites operate in Siberia (2 years), 1 in Mongolia (9 years), 3 in Korea (3 to 6 years), 3 in Japan (2 to 7 years), China 11 (6 to 0 years), Taiwan 4 (7 to 2 yrs), Viet Nam 2 (4 years), Thailand 2 to 5 (4 years), and Singapore 1 (4 months), India 1 to 3 (7 to 1 years), Pakistan 2 (1 year), and UAE 3 (3 years). An analysis of the aerosol optical depth at 500 nm using annual average quality assured AERONET data (pre 2006) was used to estimate the mean annual aerosol loading by continent, sub continent and ocean. The individual site data were assumed representative of regional aerosol loading and aggregated to the sub-continental, continental and oceanic areas and presented. This analysis will be updated with more recent data with particular emphasis on seasonal results for Asia and the addition of single scattering albedo retrievals. The ground based results will be compared to MODIS collection 5 results and model estimates for E. Asia using the AERONET Synergy Tool.

Holben, B. N.↗
NASA NTRS2011

CALIPSO Detection of an Asian Tropopause Aerosol Layer

The first four years of the CALIPSO lidar measurements have revealed the existence of an aerosol layer at the tropopause level associated with the Asian monsoon season in June, July and August. This Asian Tropopause Aerosol Layer (ATAL) extends geographically from Eastern Mediterranean (down to North Africa) to Western China (down to Thailand), and vertically from 13 to 18 km. The Scattering Ratio inferred from CALIPSO shows values between 1.10. 1.15 on average with associated depolarization ratio of less than 5%. The Gaussian distribution of the points indicates that the mean value is statistically driven by an enhancement of the background aerosol level and not by episodic events such as a volcanic eruption or cloud contamination. Further satellite observations of aerosols and gases as well as field campaigns are urgently needed to characterize this layer, which is likely to be a significant source of non-volcanic aerosols for the global upper troposphere with a potential impact on its radiative and chemical balance

Vemier, J.-P.↗
NASA NTRS2011

The Formation of Fe/Mg Smectite Under Mildly Acidic Conditions on Early Mars

The detection of Fe/Mg smectites and carbonate in Noachian and early Hesperian terrain of Mars has been used to suggest that neutral to mildly alkaline conditions prevailed during the early history of Mars. However, if early Mars was neutral to moderately alkaline with a denser CO2 atmosphere than today, then large carbonates deposits should be more widely detected in Noachian terrain. The critical question is: Why have so few carbonate deposits been detected compared to Fe/Mg smectites? We suggest that Fe/Mg smectites on early Mars formed under mildly acidic conditions, which would inhibit the extensive formation of carbonate deposits. The goal of this work is to evaluate the formation of Fe/Mg smectites under mildly acidic conditions. The stability of smectites under mildly acidic conditions is attributed to elevated Fe/Mg activities that inhibit smectite dissolution. Beidelite and saponite have been shown to form from hydrothermal alteration of basaltic glass at pH 3.5-4.0 in seawater solutions. Nontronite is also known to be stable in mildly acidic systems associated with mafic and ultramafic rock. Nontronite was shown to form in acid sulfate soils in the Bangkok Plain, Thailand due to oxidation of Fe-sulfides that transformed saponite to nontronite. Smectite is known to transform to kaolinite in naturally acid soils due to selective leaching of Mg. However, if Mg removal is limited, then based on equilibrium relationships, the dissolution of smectite should be minimized. If Fe and Mg solution activities are sufficiently high, such as might be found in a low water/rock ratio system that is poorly drained, smectite could form and remain stable under mildly acidic conditions on Mars. The sources of mild acidity on early Mars includes elevated atmospheric CO2 levels, Fe-hydrolysis reactions, and the presence of volcanic SO2 aerosols. Equilibrium calculations dictate that water equilibrated with an early Mars CO2 atmosphere at 1 to 4 bar yields a pH of 3.6 to 3.9. Fe hydrolysis reactions on Mars is another source of protons that would have contributed to acidity. The presence of SO2 from volcanic processes could also have contributed to geochemical acidification. These sources of acidity competed with base-forming cations that resulted in mildly acidic solutions that were not favorable for carbonate formation but may have allowed for Fe/Mg smectite formation. Noachian to early Hesperian Mars could have been mildly acidic, allowing Fe/Mg smectite formation but preventing widespread carbonate deposition. This paradigm shift from an early Mars that was neutral-alkaline to mildly acidic may possibly explain why there is a disparity between the occurrence of carbonate and Fe/Mg smectites. Potential microbiological activity would not be eliminated under a mildly acidic Mars; however, there could be tighter constraints as to the type and species of microbiology that could exist.

Sutter, Brad↗
NASA NTRS2013

Impact Assessment of Biomass Burning on Air Quality in Southeast and East Asia During BASE-ASIA

A synergy of numerical simulation, ground-based measurement and satellite observation was applied to evaluate the impact of biomass burning originating from Southeast Asia (SE Asia) within the framework of NASA's 2006 Biomass burning Aerosols in Southeast Asia: Smoke Impact Assessment (BASE-ASIA). Biomass burning emissions in the spring of 2006 peaked in MarcheApril when most intense biomass burning occurred in Myanmar, northern Thailand, Laos, and parts of Vietnam and Cambodia. Model performances were reasonably validated by comparing to both satellite and ground-based observations despite overestimation or underestimation occurring in specific regions due to high uncertainties of biomass burning emission. Chemical tracers of particulate K(+), OC concentrations, and OC/EC ratios showed distinct regional characteristics, suggesting biomass burning and local emission dominated the aerosol chemistry. CMAQ modeled aerosol chemical components were underestimated at most circumstances and the converted AOD values from CMAQ were biased low at about a factor of 2, probably due to the underestimation of biomass emissions. Scenario simulation indicated that the impact of biomass burning to the downwind regions spread over a large area via the Asian spring monsoon, which included Southern China, South China Sea, and Taiwan Strait. Comparison of AERONET aerosol optical properties with simulation at multi-sites clearly demonstrated the biomass burning impact via longrange transport. In the source region, the contribution from biomass burning to AOD was estimated to be over 56%. While in the downwind regions, the contribution was still significant within the range of 26%-62%.

biomass burning↗
NASA NTRS2016

Aerosol Optical Properties at the Lulin Atmospheric Background Station in Taiwan and the Influences of Long-Range Transport of Air Pollutants

The Lulin Atmospheric Background Station (LABS, 23.47 deg. N 120.87 deg. E, 2862 m ASL) in Central Taiwan was constructed in 2006 and is the only high-altitude background station in the western Pacific region for studying the influence of continental outflow. In this study, extensive optical properties of aerosols, including the aerosol light scattering coefficient [Sigma(sub s)] and light absorption coefficient [Sigma(sub a)], were collected from 2013 to 2014. The intensive optical properties, including mass scattering efficiency [Sigma(sub s)], mass absorption efficiency [Sigma(sub a)] single scattering albedo (Omega), scattering Angstrom exponent (A), and backscattering fraction (b), were determined and investigated, and the distinct seasonal cycle was observed. The value of [Alpha(sub a)] began to increase in January and reached a maximum in April; the mean in spring was 5.89 m(exp. 2) g(exp. -1) with a standard deviation (SD) of 4.54 m(exp. 2) g(exp. -1) and a 4.48 m(exp. 2) g(exp. -1) interquartile range (IQR: 2.95-7.43 m(exp. 2) g(exp. -1). The trend was similar in [Sigma(sub a)], with a maximum in March and a monthly mean of 0.84 m(exp. 2) g(exp. -1). The peak values of Omega (Mean = 0.92, SD = 0.03, IQR: 0.90 - 0.93) and A (Mean = 2.22, SD = 0.61, IQR: 2.12 = 2.47) occurred in autumn. These annual patterns of optical properties were associated with different long-range transport patterns of air pollutants such as biomass burning (BB) aerosol in spring and potential anthropogenic emissions in autumn. The optical measurements performed at LABS during spring in 2013 were compared with those simultaneously performed at the Doi Ang Kang Meteorology Station, Chiang Mai Province, Thailand (DAK, 19.93 deg. N, 99.05 deg. E, 1536 m a.s.l.), which is located in the Southeast Asia BB source region. Furthermore, the relationships among [Sigma(sub s)], [Sigma(sub a)], and (b) were used to characterize the potential aerosol types transported to LABS during different seasons, and the data were inspected according to the HYSPLIT 5-day backward trajectories, which differentiate between different regions of air mass origin.

aerosol optical properties↗