61The Tibetan Plateau (TP), known as the "sensible heat pump" and the 62 "atmospheric water tower", modifies monsoon circulations and regional energy and 63 water cycles over Asia (Wu and Zhang 1998; Zhao and Chen 2001a; Wu et al. 2007; 64 Xu et al. 2008b; Zhou et al. 2009). Strong ascent over the TP may transport lower-65 tropospheric water vapor and anthropogenic pollutants into the upper troposphere-66 lower stratosphere (UT-LS), which exerts an influence on the local ozone valley 67 (Zhou et al. 1995; Liu et al. 2003; Bian et al. 2011) and the aerosol-layer 68 enhancements near the tropopause (Tobo et al. 2007; Vernier et al. 2015). The TP also In the 1990s, a longer-term field experiment was conducted over the TP with the 84 support of the Japanese Experiment on Asian Monsoon (JEXAM). It estimated the 2008a; Zhang et al. 2012; Chen et al. 2011 Chen et al. , 2013. It found diurnal variations of et al. 2013; Hu et al. 2014; Zheng et al. 2014 Zheng et al. , 2015a Zheng et al. , b, c, 2016 Guo et al. 2015; 161 Zhuo et al. 2016; Wan et al. 2017). These problems may also cause large uncertainties 162 in reanalysis datasets and satellite products (such as air temperature, soil moisture, 163 surface heat fluxes, and radiation) over the TP (Li et al. 2012; Wang et al. 2012; Zhu 164 et al. 2012; Su et al. 2013; Zeng et al. 2016). 165To promote Tibetan meteorological research, the Third Tibetan Plateau 166Atmospheric Scientific Experiment (TIPEX-III), to continue for eight to ten years, OBJECTIVES. 173The field observational objective of TIPEX-III is to constitute a 3-D observation 174 system of the land surface, PBL, troposphere, and lower stratosphere over the TP. 175This system integrates ground-, air-, and space-based platforms based on the 176 meteorological operational networks, the TIPEX-III network, the existing NIOST (Fig. 1a). Consistent with the operational observations of the 265 CMA, at each site the measurement system measures soil water content ( Fig. 1a). The regional network consists of 33 sites over 270 Naqu (Fig. 1c), which began operating in August 2015, and 17 sites over Shiquanhe This network consists of six additional sites at Bange, Namucuo, Anduo, Nierong, 280Jiali, and Biru, and contributes to integrated research on the high-resolution land-281 surface and PBL processes over the central TP and their effects on mesoscale systems. 282These observations have been conducted at Shiquanhe, Namucuo, Naqu, Anduo, Gongshan (98.67°E, 27.75°N) station on the southeastern slope of the TP (Fig. 1b), a 300 key area for gauging water-vapor transports from the Indian Ocean to East Asia. (Fig. 1b). A primary goal of these observations is to explore the cloud (Fig. 1b). A follow-up field campaign using ground-based radars Tuotuohe, Mangya, Golmud, and Xining meteorological stations (Fig. 1b). Using PRELIMINARY ACHIEVEMENTS OF TIPEX-III. 328The implementation of TIPEX-III has enhanced the monitoring capability for the 380(1) Cloud diurnal variation and warm rain process. 3...

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Correct understanding of the land-surface processes and cloud-precipitation processes in the Tibetan Plateau (TP) is an important prerequisite for the study and forecast of the downstream activities of weather systems and one of the key points for understanding the global atmospheric movement. In order to show the achievements that have been made, this paper reviews the progress on the observations for the atmospheric boundary layer, land-surface heat fluxes, cloud-precipitation distributions and vertical structures by using ground- and space-based multiplatform, multisensor instruments and the effect of the cloud system in the TP on the downstream weather. The results show that the form drag related to the topography, land–atmosphere momentum and scalar fluxes is an important part of the parameterization process. The sensible heat flux decreased especially in the central and northern TP caused by the decrease in wind speeds and the differences in the ground-air temperatures. Observations show that the cloud and precipitation over the TP have a strong diurnal variation. Studies also show the compressed-air column in the troposphere by the higher-altitude terrain of the TP makes particles inside clouds vary at a shorter distance in the vertical direction than those in the non-plateau area so that precipitation intensity over the TP is usually small with short duration, and the vertical structure of the convective precipitation over the TP is obviously different from that in other regions. In addition, the influence of the TP on severe weather downstream is preliminarily understood from the mechanism. It is necessary to use model simulations and observation techniques to reveal the difference between cloud precipitation in the TP and non-plateau areas in order to understand the cloud microphysical parameters over the TP and the processes of the land boundary layer affecting cloud, precipitation and weather in the downstream regions.

In 2006, an emerging highly pathogenic strain of porcine reproductive and respiratory syndrome virus (PRRSV), which causes continuous high fever and a high proportion of deaths in vaccinated pigs of all ages, broke out in mainland China and spread rapidly to neighboring countries. To examine the epidemiology and evolutionary characteristics of Chinese PRRSV after the 2006 outbreak, we tested 2,981 clinical samples collected from 2006 to 2010 in China, determined 153 Nsp2 sequences and 249 ORF5 sequences, and analyzed the epidemiology and genetic diversity of Chinese PRRSV. Our results showed that the percentage of PRRSV-positive specimens collected from sick pigs averaged 60.85% in the past 5 years and that the highly pathogenic PRRSV has become the dominant strain in China. Furthermore, a reemerging strain which apparently evolved from the highly pathogenic PRRSV strain in 2006 appeared to be widely prevalent in China from 2009 onwards. Sequence analyses revealed that the hypervariable region of Nsp2 in most of the isolates contained a discontinuous deletion equivalent to 30 amino acids, along with other types of deletions. Extensive amino acid substitutions in the GP5 sequence translated from ORF5 were found, particularly in the potential neutralization epitope and the N-glycosylation sites. Our results suggest that Chinese PRRSV has undergone rapid evolution and can circumvent immune responses induced by currently used vaccines. Information from this study will help in understanding the evolutionary characteristics of Chinese PRRSV and assist ongoing efforts to develop and use PRRSV vaccines in the future.

Abstract. Air quality and visibility are strongly influenced by aerosol loading, which is driven by meteorological conditions. The quantification of their relationships is critical to understanding the physical and chemical processes and forecasting of the polluted events. We investigated and quantified the relationship between PM 2.5 (particulate matter with aerodynamic diameter is 2.5 µm and less) mass concentration, visibility and planetary boundary layer (PBL) height in this study based on the data obtained from four long-lasting haze events and seven fog-haze mixed events from January 2014 to March 2015 in Beijing. The statistical results show that there was a negative exponential function between the visibility and the PM 2.5 mass concentration for both haze and fog-haze mixed events (with the same R 2 of 0.80). However, the fog-haze events caused a more obvious decrease of visibility than that for haze events due to the formation of fog droplets that could induce higher light extinction. The PM 2.5 concentration had an inversely linear correlation with PBL height for haze events and a negative exponential correlation for fog-haze mixed events, indicating that the PM 2.5 concentration is more sensitive to PBL height in fog-haze mixed events. The visibility had positively linear correlation with the PBL height with an R 2 of 0.35 in haze events and positive exponential correlation with an R 2 of 0.56 in foghaze mixed events. We also investigated the physical mechanism responsible for these relationships between visibility, PM 2.5 concentration and PBL height through typical haze and fog-haze mixed event and found that a double inversion layer formed in both typical events and played critical roles in maintaining and enhancing the long-lasting polluted events. The variations of the double inversion layers were closely associated with the processes of long-wave radiation cooling in the nighttime and short-wave solar radiation reduction in the daytime. The upper-level stable inversion layer was formed by the persistent warm and humid southwestern airflow, while the low-level inversion layer was initially produced by the surface long-wave radiation cooling in the nighttime and maintained by the reduction of surface solar radiation in the daytime. The obvious descending process of the upper-level inversion layer induced by the radiation process could be responsible for the enhancement of the lowlevel inversion layer and the lowering PBL height, as well as high aerosol loading for these polluted events. The reduction of surface solar radiation in the daytime could be around 35 % for the haze event and 94 % for the fog-haze mixed event. Therefore, the formation and subsequent descending processes of the upper-level inversion layer should be an important factor in maintaining and strengthening the longlasting severe polluted events, which has not been revealed in previous publications. The interactions and feedbacks between PM 2.5 concentration and PBL height linked by radiation process caused a more significant an...

Despite modern sequencing efforts, the difficulty in assembly of highly repetitive sequences has prevented resolution of human genome gaps, including some in the coding regions of genes with important biological functions. One such gene, MUC5AC, encodes a large, secreted mucin, which is one of the two major secreted mucins in human airways. The MUC5AC region contains a gap in the human genome reference (hg19) across the large, highly repetitive, and complex central exon. This exon is predicted to contain imperfect tandem repeat sequences and multiple conserved cysteine-rich (CysD) domains. To resolve the MUC5AC genomic gap, we used high-fidelity long PCR followed by single molecule real-time (SMRT) sequencing. This technology yielded long sequence reads and robust coverage that allowed for de novo sequence assembly spanning the entire repetitive region. Furthermore, we used SMRT sequencing of PCR amplicons covering the central exon to identify genetic variation in four individuals. The results demonstrated the presence of segmental duplications of CysD domains, insertions/deletions (indels) of tandem repeats, and single nucleotide variants. Additional studies demonstrated that one of the identified tandem repeat insertions is tagged by nonexonic single nucleotide polymorphisms. Taken together, these data illustrate the successful utility of SMRT sequencing long reads for de novo assembly of large repetitive sequences to fill the gaps in the human genome. Characterization of the MUC5AC gene and the sequence variation in the central exon will facilitate genetic and functional studies for this critical airway mucin.

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