<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0187-6236</journal-id>
<journal-title><![CDATA[Atmósfera]]></journal-title>
<abbrev-journal-title><![CDATA[Atmósfera]]></abbrev-journal-title>
<issn>0187-6236</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Ciencias de la Atmósfera y Cambio Climático]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0187-62362021000400461</article-id>
<article-id pub-id-type="doi">10.20937/atm.52866</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Low-level windshear associated with atmospheric boundary layer jets - Case studies]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[P.W.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Hon]]></surname>
<given-names><![CDATA[K.K.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[Q.S.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Hong Kong Observatory  ]]></institution>
<addr-line><![CDATA[Kowloon Hong Kong]]></addr-line>
<country>China</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,City University of Hong Kong Department of Architecture and Civil Engineering ]]></institution>
<addr-line><![CDATA[Kowloon Hong Kong]]></addr-line>
<country>China</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2021</year>
</pub-date>
<volume>34</volume>
<numero>4</numero>
<fpage>461</fpage>
<lpage>490</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-62362021000400461&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-62362021000400461&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-62362021000400461&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT Jet streams in the atmospheric boundary layer may lead to hazardous weather over southern China. In this paper, the jet-related low-level windshear to be encountered by an aircraft is documented. Two typical cases under the northeast monsoon regime are considered, namely, easterly jet disrupted by the mountains to the south of Hong Kong International Airport, and outbreak of monsoon surge that produces a low-level northeasterly jet. The Doppler Light Detection and Ranging (LIDAR) systems are found to capture the corresponding windshear features very well, e.g., consistent with pilot reports and flight data. They are useful in providing timely alert to the aircraft. In particular, the LIDAR captures a double jet structure in the atmospheric boundary layer for the easterly wind case, which has not been reported in the literature before. The physical mechanism for the occurrence of the double jet is yet to be revealed. Moreover, the performance of a high spatial resolution (200 m) numerical weather prediction (NWP) model in predicting the jet and the associated low-level windshear is studied. The model is found to provide reasonable prediction of the windshear features at a few hours ahead, and, for the cases studied, shows skills in providing timely alerts to the aircraft.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN Las corrientes en chorro en la capa límite atmosférica pueden provocar riesgos meteorológicos en el sur de China. En este estudio se documenta un cillazamiento del viento de bajo nivel vinculado con una corriente en chorro que puede impactar a una aeronave. Se analizan dos casos típicos del régimen del monzón del noreste: un chorro del este alterado por las montañas ubicadas al sur del Aeropuerto Internacional de Hong Kong, y el surgimiento repentino del monzón que provoca una corriente en chorro de bajo nivel del noreste. Los sistemas Doppler de detección por luz y distancia (LIDAR, por sus siglas en inglés) pueden captar las características de los cillazamientos de manera consistente con los informes de los pilotos y la información de vuelo. Son útiles para proporcionar avisos oportunos a las aeronaves. En este estudio en particular, el LIDAR capta una estructura de doble corriente en chorro en la capa límite atmosférica para un caso de viento del este, el cual no se había reportado antes en la literatura. El mecanismo físico que explica la presencia de una doble corriente en chorro aún es desconocido. También se estudia el desempeño de un modelo de predicción numérica del tiempo con alta resolución espacial (200 m) para pronosticar tanto la corriente en chorro como el cizallamiento de bajo nivel asociado. Se encontró que el modelo predice razonablemente bien las características del cizallamiento con algunas horas de anticipación y, en los casos estudiados, tiene capacidad para proporcionar alertas oportunas a las aeronaves.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[windshear]]></kwd>
<kwd lng="en"><![CDATA[low-level jet]]></kwd>
<kwd lng="en"><![CDATA[LIDAR]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[PW]]></given-names>
</name>
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[ST]]></given-names>
</name>
</person-group>
<source><![CDATA[Performance of eddy dissipation rate estimates from wind profilers in turbulence detection]]></source>
<year>2004</year>
<conf-name><![CDATA[ 11th Conference on Aviation, Range, and Aerospace Meteorology]]></conf-name>
<conf-date>4-8 October</conf-date>
<conf-loc>Hyannis, MA, USA </conf-loc>
</nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[PW]]></given-names>
</name>
<name>
<surname><![CDATA[Hon]]></surname>
<given-names><![CDATA[KK]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Performance of super high resolution numerical weather prediction model in forecasting terrain-disrupted airflow at the Hong Kong International Airport: Case studies]]></article-title>
<source><![CDATA[Meteorological Aplications]]></source>
<year>2016</year>
<volume>23</volume>
<page-range>101-14</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[PW]]></given-names>
</name>
<name>
<surname><![CDATA[Hon]]></surname>
<given-names><![CDATA[KK]]></given-names>
</name>
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[QS]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A more comprehensive study of terrain-disrupted airflow at the 2 Hong Kong International Airport - Observations and numerical simulations]]></article-title>
<source><![CDATA[Weather]]></source>
<year>2019</year>
</nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chang]]></surname>
<given-names><![CDATA[KM]]></given-names>
</name>
</person-group>
<source><![CDATA[Prediction of the strength of overnight easterly winds in Hong Kong in winter. HKO Technical Note No. 79]]></source>
<year>1989</year>
</nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Du]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Heavy rainfall associated with double low-level jets over southern China. Part I: Ensemble-based analysis]]></article-title>
<source><![CDATA[Monthly Weather Review]]></source>
<year>2018</year>
<volume>146</volume>
<page-range>3827-44</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Du]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Climatology of Low-level jets and their impact on rainfall over southern China during the early-summer rainy season]]></article-title>
<source><![CDATA[Journal of Climate]]></source>
<year>2019</year>
<volume>32</volume>
<page-range>8813-33</page-range></nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="">
<collab>HKO</collab>
<source><![CDATA[Windshear and turbulence in Hong Kong - Information for pilots]]></source>
<year>2013</year>
<edition>3rd</edition>
</nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hon]]></surname>
<given-names><![CDATA[KK]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Simulated satellite imagery at sub-kilometre resolution by the Hong Kong Observatory]]></article-title>
<source><![CDATA[Weather]]></source>
<year>2018</year>
<volume>73</volume>
<page-range>139-44</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hon]]></surname>
<given-names><![CDATA[KK]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Predicting low-level windshear using 200-m resolution NWP at the Hong Kong International Airpor]]></article-title>
<source><![CDATA[Journal of Applied Meteorology and Climatology]]></source>
<year>2019</year>
</nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hon]]></surname>
<given-names><![CDATA[KK]]></given-names>
</name>
<name>
<surname><![CDATA[Tse]]></surname>
<given-names><![CDATA[SM]]></given-names>
</name>
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[PW]]></given-names>
</name>
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[QS]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Observation and real-time simulation of a tornado event in Hong Kong on 29 August 2018]]></article-title>
<source><![CDATA[Advances in Meteorology]]></source>
<year>2019</year>
<volume>2019</volume>
<page-range>8571430</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Iacono]]></surname>
<given-names><![CDATA[MJ]]></given-names>
</name>
<name>
<surname><![CDATA[Delamere]]></surname>
<given-names><![CDATA[JS]]></given-names>
</name>
<name>
<surname><![CDATA[Mlawer]]></surname>
<given-names><![CDATA[EJ]]></given-names>
</name>
<name>
<surname><![CDATA[Shephard]]></surname>
<given-names><![CDATA[MW]]></given-names>
</name>
<name>
<surname><![CDATA[Clough]]></surname>
<given-names><![CDATA[SA]]></given-names>
</name>
<name>
<surname><![CDATA[Collins]]></surname>
<given-names><![CDATA[WD]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Radiative forcing by long-lived greenhouse gases: Calculations with the AER radiative transfer models]]></article-title>
<source><![CDATA[Journal of Geophysical Research-Atmospheres]]></source>
<year>2008</year>
<volume>113</volume>
<page-range>D13103</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lai]]></surname>
<given-names><![CDATA[ST]]></given-names>
</name>
</person-group>
<source><![CDATA[Short-range forecasting of northerly surges. HKO Technical Note No. 83]]></source>
<year>1989</year>
</nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Leung]]></surname>
<given-names><![CDATA[YT]]></given-names>
</name>
<name>
<surname><![CDATA[Cheung]]></surname>
<given-names><![CDATA[HN]]></given-names>
</name>
<name>
<surname><![CDATA[Zhou]]></surname>
<given-names><![CDATA[W]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Energetics and dynamics associated with two typical mobile trough pathways over East Asia in boreal winter]]></article-title>
<source><![CDATA[Climate Dynamics]]></source>
<year>2015</year>
<volume>44</volume>
<page-range>1611-26</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lim]]></surname>
<given-names><![CDATA[K-SS]]></given-names>
</name>
<name>
<surname><![CDATA[Hong]]></surname>
<given-names><![CDATA[S-Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Development of an effective double-moment cloud microphysics scheme with prognostic cloud condensation nuclei (CCN) for weather and climate models]]></article-title>
<source><![CDATA[Monthly Weather Review]]></source>
<year>2010</year>
<volume>138</volume>
<page-range>1587-612</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Niu]]></surname>
<given-names><![CDATA[GY]]></given-names>
</name>
<name>
<surname><![CDATA[Yang]]></surname>
<given-names><![CDATA[Z-L]]></given-names>
</name>
<name>
<surname><![CDATA[Mitchell]]></surname>
<given-names><![CDATA[KE]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
<name>
<surname><![CDATA[Ek]]></surname>
<given-names><![CDATA[MB]]></given-names>
</name>
<name>
<surname><![CDATA[Barlage]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Kumar]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Manning]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<name>
<surname><![CDATA[Niyogi]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Rosero]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<name>
<surname><![CDATA[Tewari]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Xia]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The community Noah land surface model with multiparameterization options (Noah-MP): 1. Model description and evaluation with local-scale measurements]]></article-title>
<source><![CDATA[Journal of Geophysical Research]]></source>
<year>2011</year>
<volume>116</volume>
<page-range>D12109</page-range></nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Shu]]></surname>
<given-names><![CDATA[ZR]]></given-names>
</name>
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[QS]]></given-names>
</name>
<name>
<surname><![CDATA[He]]></surname>
<given-names><![CDATA[YC]]></given-names>
</name>
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[PW]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Investigation of low-level jet characteristics based on wind profiler observations]]></article-title>
<source><![CDATA[Journal of Wind Engineering and Industrial Aerodynamics]]></source>
<year>2018</year>
<volume>174</volume>
<page-range>369-81</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Shun]]></surname>
<given-names><![CDATA[CM]]></given-names>
</name>
<name>
<surname><![CDATA[Chan]]></surname>
<given-names><![CDATA[PW]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Applications of an infrared Doppler lidar in detection of wind shear]]></article-title>
<source><![CDATA[Journal of Atmospheric and Oceanic Technology]]></source>
<year>2008</year>
<volume>25</volume>
<page-range>637-55</page-range></nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Skamarock]]></surname>
<given-names><![CDATA[WC]]></given-names>
</name>
<name>
<surname><![CDATA[Klemp]]></surname>
<given-names><![CDATA[JB]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A time-split nonhydrostatic atmospheric model for weather research and forecasting applications]]></article-title>
<source><![CDATA[Journal of Computational Physics]]></source>
<year>2007</year>
<volume>227</volume>
<page-range>3465-85</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
