{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T11:48:12Z","timestamp":1784116092539,"version":"3.55.0"},"reference-count":34,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2024,11,15]],"date-time":"2024-11-15T00:00:00Z","timestamp":1731628800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42275005"],"award-info":[{"award-number":["42275005"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["BNCO-N202401"],"award-info":[{"award-number":["BNCO-N202401"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Guangxi Meteorological Science Research Program Innovation Platform Special Fund","award":["42275005"],"award-info":[{"award-number":["42275005"]}]},{"name":"Guangxi Meteorological Science Research Program Innovation Platform Special Fund","award":["BNCO-N202401"],"award-info":[{"award-number":["BNCO-N202401"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Constellation Observing System for Meteorology, Ionosphere, and Climate 2 (COSMIC-2) collects data covering latitudes primarily between 40 degrees north and south, providing abundant data for tropical cyclone (TC) research. The radio occultation data provide valuable information on the boundary layer. However, quality control of the data within the boundary layer remains a challenging issue. The aim of this study is to obtain a more accurate COSMIC-2 radio occultation (RO) dataset through quality control (QC) and use this dataset to validate warm core structures and explore the planetary boundary layer (PBL) structures of TCs. In this study, COSMIC-2 data are used to analyze the distribution of the relative local spectral width (LSW) and the confidence parameter characterizing the random error of the bending angle. An LSW less than 20% is set as a data QC threshold, and the warm core and PBL composite structures of TCs at three intensities in the Northwest Pacific Ocean are investigated. We reproduce the warm core intensity and warm core height characteristics of TCs. In the radial direction of the typhoon eyewall, the impact height of the PBL increases from 3.45 km to 4 km, with the tropopause ranging from 160 hPa to 100 hPa. At the bottom of the troposphere, the variations in the positive and negative bias between the RO-detected and background field bending angles correspond well to the PBL heights, and the variations in the positive bias between the RO-detected and background field refractivity reach 14%. This research provides an effective QC method and reveals that the bending angle is sensitive to the PBL height.<\/jats:p>","DOI":"10.3390\/rs16224257","type":"journal-article","created":{"date-parts":[[2024,11,15]],"date-time":"2024-11-15T04:47:17Z","timestamp":1731646037000},"page":"4257","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Investigating Tropical Cyclone Warm Core and Boundary Layer Structures with Constellation Observing System for Meteorology, Ionosphere, and Climate 2 Radio Occultation Data"],"prefix":"10.3390","volume":"16","author":[{"given":"Xiaoxu","family":"Qi","sequence":"first","affiliation":[{"name":"Joint Center of Data Assimilation for Research and Application, School of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China"},{"name":"Laboratory of Beibu Gulf National Climate Observatory, Guangxi Research Institute of Meteorological Science, Nanning 530022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0557-8106","authenticated-orcid":false,"given":"Shengpeng","family":"Yang","sequence":"additional","affiliation":[{"name":"Joint Center of Data Assimilation for Research and Application, School of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China"},{"name":"Laboratory of Beibu Gulf National Climate Observatory, Guangxi Research Institute of Meteorological Science, Nanning 530022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"He","sequence":"additional","affiliation":[{"name":"Laboratory of Beibu Gulf National Climate Observatory, Guangxi Research Institute of Meteorological Science, Nanning 530022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1657","DOI":"10.1175\/JAS-D-11-010.1","article-title":"On the Height of the Warm Core in Tropical Cyclones","volume":"69","author":"Stern","year":"2012","journal-title":"J. Atmos. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"773","DOI":"10.1175\/MWR-D-18-0276.1","article-title":"A 13-Year Global Climatology of Tropical Cyclone Warm-Core Structures from AIRS Data","volume":"147","author":"Wang","year":"2019","journal-title":"Mon. Weather Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1175\/1520-0469(1990)047<0265:GBITC>2.0.CO;2","article-title":"Gradient balance in tropical cyclones","volume":"47","author":"Willoughby","year":"1990","journal-title":"J. Atmos. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2519","DOI":"10.1175\/1520-0469(1997)054<2519:TMPIOT>2.0.CO;2","article-title":"The maximum potential intensity of tropical cyclones","volume":"54","author":"Holland","year":"1997","journal-title":"J. Atmos. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1002\/qj.235","article-title":"Tropical-cyclone intensification and predictability in three dimensions","volume":"134","author":"Nguyen","year":"2008","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"355","DOI":"10.1175\/JAS3604.1","article-title":"A vortical hot tower route to tropical cyclogenesis","volume":"63","author":"Montgomery","year":"2006","journal-title":"J. Atmos. Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1209","DOI":"10.1175\/1520-0469(2004)061<1209:TROVHT>2.0.CO;2","article-title":"The role of \u201cvortical\u201d hot towers in the formation of tropical cyclone Diana (1984)","volume":"61","author":"Hendricks","year":"2004","journal-title":"J. Atmos. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4256","DOI":"10.1175\/MWR-D-13-00021.1","article-title":"Observed tropical cyclone eye thermal anomaly profiles extending above 300 hpa","volume":"141","author":"Durden","year":"2013","journal-title":"Mon. Weather Rev."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3402\/tellusa.v12i1.9351","article-title":"On the dynamics and energy transformations in steady state hurricanes","volume":"12","author":"Malkus","year":"1960","journal-title":"Tellus"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2375","DOI":"10.1007\/s00382-021-05806-9","article-title":"Characteristics of warm cores of tropical cyclones in a 25-km-mesh regional climate simulation over CORDEX East Asia domain","volume":"57","author":"Xi","year":"2021","journal-title":"Clim. Dyn."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"e2019GL086841","DOI":"10.1029\/2019GL086841","article-title":"COSMIC-2 Radio Occultation Constellation: First Results","volume":"47","author":"Schreiner","year":"2020","journal-title":"Geophys. Res. Lett."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Ho, S.P., Zhou, X., Shao, X., Zhang, B., Adhikari, L., Kireev, S., He, Y., Yoe, J.G., Xia-Serafino, W., and Lynch, E. (2020). Initial assessment of the COSMIC-2\/FORMOSAT-7 neutral atmosphere data quality in NESDIS\/STAR using in situ and satellite data. Remote Sens., 12.","DOI":"10.3390\/rs12244099"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"4289","DOI":"10.1175\/JAS-D-15-0318.1","article-title":"Warm Cores, Eyewall Slopes, and Intensities of Tropical Cyclones Simulated by a 7-km-Mesh Global Nonhydrostatic Model","volume":"73","author":"Ohno","year":"2016","journal-title":"J. Atmos. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1007\/s00376-019-8274-z","article-title":"Analysis of an ensemble of high-resolution WRF simulations for the rapid intensification of Super Typhoon Rammasun (2014)","volume":"37","author":"Li","year":"2020","journal-title":"Adv. Atmos. Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e2023JD039410","DOI":"10.1029\/2023JD039410","article-title":"Comparison of cloud\/rain band structures of Typhoon Muifa (2022) revealed in FY-3E MWHS-2 observations with all-sky simulations","volume":"128","author":"Bi","year":"2023","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2509","DOI":"10.1175\/JAS-D-17-0315.1","article-title":"Capturing Size and Intensity Changes of Hurricanes Irma and Maria (2017) from Polar-Orbiting Satellite Microwave Radiometers","volume":"75","author":"Tian","year":"2018","journal-title":"J. Atmos. Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2261","DOI":"10.1175\/MWR-D-18-0391.1","article-title":"Using Deep Learning to Estimate Tropical Cyclone Intensity from Satellite Passive Microwave Imagery","volume":"147","author":"Wimmers","year":"2019","journal-title":"Mon. Weather Rev."},{"key":"ref_18","first-page":"2097","article-title":"Physics-Augmented Deep Learning to Improve Tropical Cyclone Intensity and Size Estimation from Satellite Imagery","volume":"149","author":"Zhuo","year":"2021","journal-title":"Mon. Weather Rev."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"925","DOI":"10.3319\/TAO.2021.06.14.01","article-title":"COSMIC-2 radio occultation temperature, specific humidity, and precipitable water in Hurricane Dorian (2019)","volume":"32","author":"Anthes","year":"2021","journal-title":"Terr. Atmos. Ocean. Sci."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1029\/2010GL043299","article-title":"Super-refraction effects on GPS radio occultation refractivity in marine boundary layers","volume":"37","author":"Xie","year":"2010","journal-title":"Geophys. Res. Lett."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Wang, L., Yang, S., and Lin, L. (2022). Tropical Cyclone Planetary Boundary Layer Heights Derived from GPS Radio Occultation over the Western Pacific Ocean. Remote Sens., 14.","DOI":"10.3390\/rs14236110"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Garn\u00e9s-Morales, G., Costa, M.J., Bravo-Aranda, J.A., Granados-Mu\u00f1oz, M.J., Salgueiro, V., Abril-Gago, J., Fern\u00e1ndez-Carvelo, S., And\u00fajar-Maqueda, J., Valenzuela, A., and Foyo-Moreno, I. (2024). Four Years of Atmospheric Boundary Layer Height Retrievals Using COSMIC-2 Satellite Data. Remote Sens., 16.","DOI":"10.3390\/rs16091632"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"507","DOI":"10.2151\/jmsj.2004.507","article-title":"Inversion and error estimation of GPS radio occultation data","volume":"82","author":"Kuo","year":"2004","journal-title":"J. Meteorol. Soc. Jpn."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"8557","DOI":"10.1175\/JCLI-D-18-0074.1","article-title":"Comparison of TC Temperature and Water Vapor Climatologies between the Atlantic and Pacific Oceans from GPS RO Observations","volume":"31","author":"Yang","year":"2018","journal-title":"J. Clim."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1040","DOI":"10.1029\/2002RS002763","article-title":"Full spectrum inversion of radio occultation signals","volume":"38","author":"Jensen","year":"2003","journal-title":"Radio Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1029\/2003RS002899","article-title":"Geometric optics phase matching of radio occultation signals","volume":"39","author":"Jensen","year":"2004","journal-title":"Radio Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"D10","DOI":"10.1029\/2005JD006427","article-title":"Radio holographic filtering, error estimation, and quality control of radio occultation data","volume":"111","author":"Gorbunov","year":"2006","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"2117","DOI":"10.1175\/JTECH-D-17-0224.1","article-title":"A Quality Control Procedure Based on Bending Angle Measurement Uncertainty for Radio Occultation Data Assimilation in the Tropical Lower Troposphere","volume":"35","author":"Liu","year":"2018","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Zou, X. (2020). Global positioning system radio occultation observations. Atmospheric Satellite Observations, Academic Press.","DOI":"10.1016\/B978-0-12-820950-9.00010-6"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Rogers, R.F. (2021). Recent Advances in Our Understanding of Tropical Cyclone Intensity Change Processes from Airborne Observations. Atmosphere, 12.","DOI":"10.3390\/atmos12050650"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"647","DOI":"10.1002\/qj.3938","article-title":"Estimating GPS radio occultation observation error standard deviations over China using the three-cornered hat method","volume":"147","author":"Xu","year":"2020","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"D6","DOI":"10.1029\/2011JD016452","article-title":"Assessments of cloud liquid water contributions to GPS radio occultation refractivity using measurements from COSMIC and CloudSat","volume":"117","author":"Yang","year":"2012","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"3670","DOI":"10.1175\/JAS-D-11-0199.1","article-title":"Impacts of Ice Clouds on GPS Radio Occultation Measurements","volume":"69","author":"Zou","year":"2012","journal-title":"J. Atmos. Sci."},{"key":"ref_34","first-page":"1351","article-title":"Bias Characteristics of COSMIC RO Data within Clouds Based on Different Background Fields","volume":"42","author":"Yin","year":"2023","journal-title":"Plateau Meteorol."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/16\/22\/4257\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:32:58Z","timestamp":1760113978000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/16\/22\/4257"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,11,15]]},"references-count":34,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2024,11]]}},"alternative-id":["rs16224257"],"URL":"https:\/\/doi.org\/10.3390\/rs16224257","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,11,15]]}}}