20 research outputs found
USING THE TWO-LEVEL MORPHOLOGY ON MODERN MONGOLIAN LINGUISTICS
This study compiles primarily the word structure of Modern Mongolian language and further more focused on the possibilities of description of Mongolian language in PC KIMMO, a two level processing method of morphological parsing. The rules file and lexicon presented in the paper describe the morphology of Mongolian words. A lexicon containing the root words of contemporary Mongolian is used in the testing. As a result the two-level morphology is determined as completely possible to be used for Mongolian linguistics. In addition PC-KIMMO description of traditional Mongolian script is considered as being possible
Examining TROPOMI formaldehyde to nitrogen dioxide ratios in the Lake Michigan region: implications for ozone exceedances
Surface-level ozone (O3) is a secondary air pollutant that has adverse effects on human health. In the troposphere, O3 is
produced in complex cycles of photochemical reactions involving nitrogen oxides (NOx) and volatile organic compounds
(VOCs). Determining if O3 levels will be decreased by lowering NOx emissions
(“NOx-sensitive”), VOC emissions (“VOC-sensitive”), or both (“the transition zone”) can be done by using the
formaldehyde (HCHO; a VOC species) to nitrogen dioxide (NO2; a component of NOx) concentration ratio
(HCHO/NO2; “FNR”). Generally, lower FNR values indicate VOC sensitivity, while higher values indicate
NOx sensitivity. Despite being a highly populated region with coastal O3 air quality issues, the Lake Michigan region in
the United States, including the Chicago, Illinois, metropolitan area (CMA), remains relatively understudied, especially from the satellite
perspective. In this work, we present the first study that utilizes TROPOspheric Monitoring Instrument (TROPOMI) satellite data over the Lake
Michigan region from 2019–2021 to assess changes in O3 precursor levels and the inferred O3 chemistry sensitivity between
(1) O3 season days and CMA O3 exceedance days and (2) weekdays and weekends. Higher NO2 vertical column densities
(VCDs), HCHO VCDs, and FNR values are seen throughout the study domain on exceedance days, indicating generally more
NOx-sensitive O3 chemistry. The largest change occurs in the areal extent of the transition zone, which decreases
by 40 % during exceedance days. Major urban cores in the domain (e.g., Chicago, Illinois; Gary, Indiana; and Milwaukee, Wisconsin) remain
VOC-sensitive on exceedance days as the higher NO2 VCDs in these areas counterbalance the regionally higher HCHO
VCDs. Utilizing 10 m wind analysis data, we show that the lake breeze circulation is stronger on exceedance days. The strengthening of the
lake breeze causes stronger convergence of the wind field along the southwestern Lake Michigan coastline, which can concentrate
NO2 emissions originating in this area. This finding provides a possible explanation for the higher TROPOMI NO2 VCDs over the
urban core of Chicago on exceedance days. Investigation of 2 m air temperature analysis data reveals that temperatures are higher on
exceedance days, which explains the stronger lake breeze circulation and provides a possible cause for the higher TROPOMI HCHO VCDs over the
entire region (due to increased temperature-dependent biogenic VOC emissions). Comparing weekdays and weekends, higher FNR values throughout
much of the region indicate increasingly NOx-sensitive O3 chemistry on weekends. These changes are driven by lower
NO2 VCDs in urban areas, particularly in Chicago, and higher HCHO VCDs in the southern part of the domain on weekends. Overall, our
analyses suggest that VOC emissions controls in major urban areas and NOx emissions controls throughout the entire domain
are necessary to decrease O3 levels in the Lake Michigan region.</p
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Anthropogenic Influences on 2019 July Precipitation Extremes Over the Mid–Lower Reaches of the Yangtze River
Understanding the driving factors for precipitation extremes matters for adaptation and mitigation measures against the changing hydrometeorological hazards in Yangtze River basin, a habitable area that provides water resources for domestic, farming, and industrial needs. However, the region is naturally subject to major floods linked to monsoonal heavy precipitation during May–September. This study aims to quantify anthropogenic influences on the changing risk of 2-week-long precipitation extremes such as the July 2019 extreme cases, as well as events of shorter durations, over the middle and lower reaches of Yangtze River basin (MLYRB). Precipitation extremes with different durations ranging from 1-day to 14-days maximum precipitation accumulations are investigated. Gridded daily precipitations based on nearly 2,400 meteorological stations across China are used to define maximum accumulated precipitation extremes over the MLYRB in July during 1961–2019. Attribution analysis is conducted by using the Met Office HadGEM3-GA6 modeling system, which comprises two sets of 525-member ensembles for 2019. One is forced with observed sea-surface temperatures (SSTs), sea-ice and all forcings, and the other is forced with preindustrialized SSTs and natural forcings only. The risk ratio between the exceedance probabilities estimated from all-forcing and natural-forcing simulations is calculated to quantify the anthropogenic contribution to the changing risks of the July 2019–like precipitation extremes. The results reveal that anthropogenic warming has reduced the likelihood of 2019-like 14-days heavy precipitation over the mid–lower reaches of the Yangtze River by 20%, but increased that of 2-days extremes by 30%
Meteorological modeling sensitivity to parameterizations and satellite-derived surface datasets during the 2017 Lake Michigan Ozone Study
High-resolution simulations were performed to assess the impact of different parameterization schemes, surface datasets, and analysis nudging on lower-tropospheric conditions near Lake Michigan. Simulations were performed where climatological or coarse-resolution surface datasets were replaced by high-resolution, real-time datasets depicting the lake surface
temperatures (SSTs), green vegetation fraction (GVF), and soil moisture and
temperature (SOIL). Comparison of two baseline simulations employing
different parameterization schemes (referred to as AP-XM and YNT, respectively) showed that the AP-XM simulation produced more accurate analyses on the outermost 12 km resolution domain but that the YNT simulation was superior for higher-resolution nests. The diurnal evolution of the surface energy fluxes was similar in both simulations on the 12 km grid but differed greatly on the 1.3 km grid where the AP-XM simulation had a much smaller sensible heat flux during the daytime and a physically unrealistic ground heat flux. Switching to the YNT configuration led to more accurate 2 m temperature and 2 m water vapor mixing ratio analyses on the 1.3 km grid. Additional improvements occurred when satellite-derived surface datasets were incorporated into the modeling platform, with the SOIL dataset having the largest positive impact on temperature and water vapor. The GVF and SST datasets also produced more accurate temperature and water vapor analyses but had degradations in wind speed, especially when using the GVF dataset. The most accurate simulations were obtained when using the high-resolution SST and SOIL datasets and analysis nudging above 2 km a.g.l. (above ground level). These results demonstrate the value of using high-resolution satellite-derived surface datasets in model simulations.</p
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BioEarth: Envisioning and developing a new regional earth system model to inform natural and agricultural resource management
As managers of agricultural and natural resources are confronted with uncertainties in global change impacts, the complexities associated with the interconnected cycling of nitrogen, carbon, and water present daunting management challenges. Existing models provide detailed information on specific sub-systems (e.g., land, air, water, and economics). An increasing awareness of the unintended consequences of management decisions resulting from interconnectedness of these sub-systems, however, necessitates coupled regional earth system models (EaSMs). Decision makers’ needs and priorities can be integrated into the model design and development processes to enhance decision-making relevance and “usability” of EaSMs. BioEarth is a research initiative currently under development with a focus on the U.S. Pacific Northwest region that explores the coupling of multiple stand-alone EaSMs to generate usable information for resource decision-making. Direct engagement between model developers and non-academic stakeholders involved in resource and environmental management decisions throughout the model development process is a critical component of this effort. BioEarth utilizes a bottom-up approach for its land surface model that preserves fine spatial-scale sensitivities and lateral hydrologic connectivity, which makes it unique among many regional EaSMs. This paper describes the BioEarth initiative and highlights opportunities and challenges associated with coupling multiple stand-alone models to generate usable information for agricultural and natural resource decision-making
Diatoms (Bacillariophyceae) from the Valley of the Great Lakes in Western Mongolia
T
he Valley of the Great Lakes (VOGL) in western Mongolia is dominated by two main (Uvs,
Khyargas) and many minor closed basin lake systems. In 2004 and 2005, we sampled diatom
communities from the surfi cial sediment of 64 lakes in the western Mongolian provinces of Uvs, Khovd,
Zavkhan, and Bayan-Ulgii. Lakes ranged in water chemistry from fresh to hypersaline, oligotrophic to
hypertrophic, and from low elevation VOGL lakes to high elevation lakes in the Altai Mountains. Over
300 diatom species were identifi ed in the sediment samples including a diverse fl ora limited to saline
lakes, many widespread taxa, many new reports for the Mongolian diatom fl ora, and several new and
possibly endemic species. We also review recent diatom literature from Mongolia including fl oristic
surveys, paleo-ecology, and water quality studies
Space geodetic activities at the Astronomical Observatory of Mongolia
We present in this paper some results obtained
in the field of space geodesy based on continuous GPS observations
at the Astronomical Observatory of Mongolia.
Starting with a brief historical overview of the main space
geodetic activities carried out by the Astronomical Observatory
in the past, we outline here current achievements
in the application of GPS techniques in the geosciences
research in Mongolia. We setup a local GNSS Data Center
of the Mongolian Academy of Sciences to receive, quality
control and process into derivative products the observation
data coming from its continuously recording stations.
The quality check performed on three non-real-time
permanent stations reveals that all three stations show
smooth trends of each parameter indicating good quality
in data record and operation without any anomalous behavior
Impacts of Open Placer Gold Mining on Aquatic Communities in Rivers of the Khentii Mountains, North-East Mongolia
Since
the political change and due to high market prices for gold the mining sector has consid-
erably grown in Mongolia and has become one of the most important economical sectors. With in-
creasing mining activities the mining related environmental problems also increased, especially those,
which are caused by open placer gold mining. Placer gold deposits are located in the alluvial sedi-
ments of river
fl oodplains and the exploitation of these deposits often induces severe impacts to river
ecosystem and its different components. In this paper we describe the effects of open placer gold min-
ing on diatoms, benthic invertebrates and fi sh in four rivers in the north-east of Mongolia. Our fi ndings
are based on a comparative analysis of these biocoenotic groups in pristine and mining affected river
sections, taking into account also abiotic habitat characteristics. Our analyses revealed that placer gold
mining causes multiple stressors acting on different trophic levels. The biocoenotic groups under in-
vestigation reacted differently against stressors, and we indentifi ed a wide range of direct and indirect
effects. These fi ndings are new for Mongolia and are essential to defi ne adapted and successful strate-
gies for an ecologically based management and monitoring of open placer gold mining pressures and
ecological impacts