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We have studied the Asian dust emitted from a hotspot in the Gobi Desert by a lidar network, analyses of Himawari-8 Dust RGB and meteorological fields, and a field survey since 2013. We found a remarkable dust hotspot in the Gobi Desert by the filed survey and analysis. The Himawari-8 Dust RGB imagery shows that the dust storm occurred in an orographic convergence zone sandwiched between the Khangai, Altai, and Gurvan Saikhan Mountains in the Gobi Desert. The lidar network operating in Dalanzadgad, Sainshand, and Zamyn-Uud, Mongolia shows a dust layer development over the Gobi Desert in association with a cold frontal system and the long-range transport of the dust. We estimated the massextinction conversion factor MECF (g m-2) from simultaneous observations using an optical particle counter (OPC) installed on a tethered balloon and a ceilometer in the Gobi Desert. The MECF values decreased from the Asian dust source (Dalanzadgad 1.91 g m-2) to the lee-side areas (e.g., Tsukuba 1.18 g m-2) due to the gravitational settling of large dust particles.

AD-Net, the Asian dust and aerosol lidar observation network, is operated in East Asian counties for creating useful dataset for environmental impact studies. The products from AD-Net have been utilized as the source of data assimilation in a chemical transport model, and as the index of exposure of Asian dust to human in the area. Long term observation is indispensable to estimate climatorogical change of dust density, and sustainable operation strategies are needed for further development of regional lidar network.

The paper presents the preliminary results of the lidar&radiometer measurement campaign (LRMC-2017), estimation of statistical relations between aerosol mode concentrations retrieved from CALIOP and ground-based lidar stations and case study of fire smoke events in the Eurasian regions using combined ground-based and space lidar and radiometer observations.

Mineral dust generated in Africa and Middle East is sometimes transported to East Asia. Some cases were observed with the Asian Dust and aerosol lidar observation Network (AD-Net). In the large Sahara dust event in March 2018, which was reported by mass media as that snow in Sochi, Russia was stained into orange, the dust was transported to Sapporo, Japan in 4 days from Sochi and observed with the AD-Net lidar. Sahara dust events were also observed in April 2017 and April 2018 with AD-Net. The source areas and transport paths were studied with chemical transport models and trajectory analysis and also confirmed with CALIPSO data. This study showed that long-range transport from Africa and Middle East to East Asia is not rare in springtime.

AD-Net is an aerosol observation network using continuously operated multi-parameter lidars consists of 20 stations in East Asia. It is a “contributing network” of the WMO Global Atmosphere Watch (GAW) Program and is an Asian component of the GAW Aerosol Lidar Observation Network (GALION). The standard lidars in AD-Net are two-wavelength (1064 and 532 nm) and polarization (532 nm) lidars, but multiwavelength Raman lidars and a multiwavelength high-spectral-resolution (532 nm) and Raman (355 nm) lidar are also employed. The Mie scattering data from the AD-Net lidars are processed in near realtime (every hour) and published on the AD-Net www page in NetCDF format and graphical indications. AD-Net data are used in monitoring and various studies of Asian dust and regional air pollution. Analyses combining with chemical transport models showed that dust affecting the lower troposphere in Japan was mostly from the Gobi Desert, and dust from the Taklamakan was often transported in the free troposphere very long range. A case of Sahara dust transported through the Middle East and Central Asia was also found. Asian dust transported through polluted areas in East Asia is often internally mixed with air pollution. Results of studies using AD-Net lidars, in-situ polarization particle counters (POPCs), and sampling measurements of chemical composition are introduced.

Long-term sustained heavy Asian Dust below 3 km was measured in the period of April 22-26 by 2-wavelengths depolarization lidar system. As the comparison results of Daejeon station with other stations in the AD-Net, similarly formed Asian dust had been measured at Nigata, Toyama, Matsue, and Sendai. The route of the dust was examined by HYSPLIT. More than 80 μg / m3 mass concentrations derived from the lidar measurements were compared with Air-Korea PM10 data.

Recent developments of lidars and data analysis methods for AD-Net, and the studies using ADNet are presented. Continuous observation was started in 2001 at three stations using polarizationsensitive Mie-scattering lidars. Currently, lidars, including three multi-wavelength Raman lidars and one high-spectral-resolution lidar, are operated at 20 stations. Recent studies on validation/assimilation of chemical transport models, climatology, and epidemiology of Asian dust are also described.

Multi-field of view multiple-scattering polarization lidar (MFMSPL) has been developed to measure enhanced backscattering and depolarization ratio from optically thick clouds. Collocated cloud radar observations and Monte Carlo simulations supported the system performance such as cloud detectability and values of depolarization ratio. The system is used to evaluate/improve algorithms for space-borne lidar such as CALIOP on CALIPSO and ATLID on EarthCARE.

We deployed multi-wavelength Mie-Raman lidars (MMRL) at three sites of the AD-Net and have conducted continuous measurements using them since 2013. To analyze the MMRL data and better understand the externally mixing state of main aerosol components (e.g., dust, sea-salt, and black carbon) in the atmosphere, we developed an integrated package of aerosol component retrieval algorithms, which have already been developed or are being developed, to estimate vertical profiles of the aerosol components. This package applies to the other ground-based lidar network data (e.g., EARLINET) and satellite-borne lidar data (e.g., CALIOP/CALIPSO and ATLID/EarthCARE) as well as the other lidar data of the AD-Net.

The South American Environmental Risk Management Network (SAVER-Net) is an instrumentation network, mainly composed by lidars, to provide real-time information for atmospheric hazards and risk management purposes in South America. This lidar network have been developed since 2012 and all its sampling points are expected to be fully implemented by 2017. This paper describes the network’s status and configuration, the data acquisition and processing scheme (protocols and data levels), as well as some aspects of the scientific networking in Latin American Lidar Network (LALINET). Similarly, the paper lays out future plans on the operation and integration to major international collaborative efforts.

A tropospheric lidar system was installed in Punta Arenas, Chile (53.13°S, 70.88°W) in September 2016 under the collaboration project SAVERNET (Chile, Japan and Argentina) to monitor the atmosphere. Statistical analyses of the clouds and aerosols behavior and some cases of dust detected with lidar, at these high southern latitude and cold environment regions during three months (austral spring) are discussed using information from satellite, modelling and solar radiation ground measurements.

We have developed the Multiple Field of view Multiple Scattering Polarization Lidar (MFMSPL) system for the study of optically thick low-level clouds. It has 8 telescopes; 4 telescopes for parallel channels and another 4 for perpendicular channels. The MFMSPL is the first lidar system that can measure depolarization ratio for optically thick clouds where multiple scattering is dominant. Field of view of each channel was 10mrad and was mounted with different angles ranging from 0 mrad (vertical) to 30mrad. And footprint size from the total FOV was achieved to be close to that of Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) lidar at the altitude of 1km in order to reproduce similar degree of multiple scattering effects as observed from space. The MFMSPL has started observations since June 2014 and has been continuously operated at National Institute for Environmental Studies (NIES) in Tsukuba, Japan. Observations proved expected performance such that measured depolarization ratio was comparable to the one observed by CALIPSO lidar.

We have operated a ground-based lidar network AD-Net using dual wavelength (532, 1064nm) depolarization Mie lidar continuously and observed movement of Asian dust and air pollution aerosols in East Asia since 2001. This lidar network observation contributed to understanding of the occurrence and transport mechanisms of Asian dust, validation of chemical transport models, data assimilation and epidemiologic studies. To better understand the optical and microphysical properties, externally and internally mixing states, and the movements of Asian dust and airpollution aerosols, we go forward with introducing a multi-wavelength Raman lidar to the AD-Net and developing a multi-wavelength technique of HSRL in order to evaluate optical concentrations of more aerosol components. We will use this evolving AD-Net for validation of Earth-CARE satellite observation and data assimilation to evaluate emissions of air pollution and dust aerosols in East Asia. We go forward with deploying an in-situ instrument polarization optical particle counter (POPC), which can measure size distributions and non-sphericity of aerosols, to several main AD-Net sites and conducting simultaneous observation of POPC and lidar to clarify internally mixed state of Asian dust and air pollution aerosols transported from the Asian continent to Japan.

Two main decisions were made in Argentina to mitigate the impact of the recent volcanic activity in de country basically affected by the presence of volcanic ash in the air and deposited over the Argentinean territory. The first one was to create a risk management commission were this risk between others were studied, and second to develop new ground based remote sensing technologies to be able to identify and inform the risk close to the airports. In addition the Japanese government program for Science and Technology joint Research Partnership between Argentina, Chile and Japan for Sustainable Development (SATREPS) accepted to fund this cooperation due to the potential future utilization of the research outcomes to the benefit of the society. This work present the actual achievements and expected advance of these projects that try to joint efforts between national and international agencies as well as countries on behalf of a better understanding of the risks and a joint collaboration on the mitigation of suspended ashes impact over the aerial navigation.

Mie-scattering lidar data are going to be incorporated into data assimilation in chemical transport model to represent more reliable / useful horizontal distribution of Asian dust over Japan. The result is utilized in an epidemiology which surveys effect of Asian dust to human health. Wider application of AD-Net is expected in the field of environmental researches.

Abstract Background Higher crustaceans (class Malacostraca) represent the most species-rich and morphologically diverse group of non-insect arthropods and many of its members are commercially important. Although the crustacean DNA sequence information is growing exponentially, little is known about the genome organization of Malacostraca. Here, we constructed a bacterial artificial chromosome (BAC) library and performed BAC-end sequencing to provide genomic information for kuruma shrimp (Marsupenaeus japonicus), one of the most widely cultured species among crustaceans, and found the presence of a redundant sequence in the BAC library. We examined the BAC clone that includes the redundant sequence to further analyze its length, copy number and location in the kuruma shrimp genome. Results Mj024A04 BAC clone, which includes one redundant sequence, contained 27 putative genes and seemed to display a normal genomic DNA structure. Notably, of the putative genes, 3 genes encode homologous proteins to the inhibitor of apoptosis protein and 7 genes encode homologous proteins to white spot syndrome virus, a virulent pathogen known to affect crustaceans. Colony hybridization and PCR analysis of 381 BAC clones showed that almost half of the BAC clones maintain DNA segments whose sequences are homologous to the representative BAC clone Mj024A04. The Mj024A04 partial sequence was detected multiple times in the kuruma shrimp nuclear genome with a calculated copy number of at least 100. Microsatellites based BAC genotyping clearly showed that Mj024A04 homologous sequences were cloned from at least 48 different chromosomal loci. The absence of micro-syntenic relationships with the available genomic sequences of Daphnia and Drosophila suggests the uniqueness of these fragments in kuruma shrimp from current arthropod genome sequences. Conclusions Our results demonstrate that hyper-expansion of large DNA segments took place in the kuruma shrimp genome. Although we analyzed only a part of the duplicated DNA segments, our result suggested that it is difficult to analyze the shrimp genome following normal analytical methodology. Hence, it is necessary to avoid repetitive sequence (such as segmental duplications) when studying the other unique structures in the shrimp genome.

Abstract Background Defensins are important components of innate immunity to combat bacterial and viral infections, and can even elicit antitumor responses. Clusters of defensin (DEF) genes are located in a 2 Mb range of the human chromosome 8p23.1. This DEF locus, however, represents one of the regions in the euchromatic part of the final human genome sequence which contains segmental duplications, and recalcitrant gaps indicating high structural dynamics. Results We find that inter- and intraindividual genetic variations within this locus prevent a correct automatic assembly of the human reference genome (NCBI Build 34) which currently even contains misassemblies. Manual clone-by-clone alignment and gene annotation as well as repeat and SNP/haplotype analyses result in an alternative alignment significantly improving the DEF locus representation. Our assembly better reflects the experimentally verified variability of DEF gene and DEF cluster copy numbers. It contains an additional DEF cluster which we propose to reside between two already known clusters. Furthermore, manual annotation revealed a novel DEF gene and several pseudogenes expanding the hitherto known DEF repertoire. Analyses of BAC and working draft sequences of the chimpanzee indicates that its DEF region is also complex as in humans and DEF genes and a cluster are multiplied. Comparative analysis of human and chimpanzee DEF genes identified differences affecting the protein structure. Whether this might contribute to differences in disease susceptibility between man and ape remains to be solved. For the determination of individual DEF gene repertoires we provide a molecular approach based on DEF haplotypes. Conclusions Complexity and variability seem to be essential genomic features of the human DEF locus at 8p23.1 and provides an ongoing challenge for the best possible representation in the human reference sequence. Dissection of paralogous sequence variations, duplicon SNPs ans multisite variations as well as haplotypes by sequencing based methods is the way for future studies of interindividual DEF locus variability and its disease association.