AMTD Atmospheric Measurement Techniques Discussions AMTD Atmos. Meas. Tech. Discuss. 1867-8610 Göttingen, Germany 10.5194/amt-2019-379 Comparison of RO tropopause height based on different tropopause determination methods Liu Ziyan 1 2 3 Bai Weihua 1 2 Sun Yueqiang 1 2 Xia Junming 1 2 Tan Guangyuan 1 2 3 Cheng Cheng 4 Du Qifei 1 2 Wang Xianyi 1 2 Zhao Danyang 1 2 Tian Yusen 1 2 3 Meng Xiangguang 1 2 Liu Congliang 1 2 Cai Yuerong 1 2 Wang Dongwei 1 2 National Space Science Centre, Chinese Academy of Sciences (NSSC/CAS), Beijing 100190, China Beijing Key Laboratory of Space Environment Exploration, Beijing 100190, China University of Chinese Academy of Sciences, Beijing 100049, China State Intellectual Property Office of the P.R.C, Beijing 100088, China National Natural Science Foundation of China 41405039 41775034 41405040 41505016 41505030 41606206 XDA15007501 YZ201129 30 10 2019 2019 1 19 Copyright: © 2019 Ziyan Liu et al. 2019 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/ This article is available from https://amt.copernicus.org/preprints/amt-2019-379/ The full text article is available as a PDF file from https://amt.copernicus.org/preprints/amt-2019-379/amt-2019-379.pdf

<p>Tropopause region is a significant layer among the earth's atmosphere, receiving increasing attention from atmosphere and climate researchers. To monitor global tropopause via radio occultation (RO) data, there are mainly two methods, one is the widely used temperature lapse rate method, and the other is bending angle covariance transform method. In this paper, we use FengYun3-C (FY3C) and Meteorological Operational Satellite Program (MetOp) RO data and European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis data to analyse the difference of RO tropopause height calculated by the two methods mentioned above. To give an objective and complete analysis, we first take ECMWF lapse rate tropopause (LRT) height (LRTH) as reference to discuss the absolute bias of RO LRTH and RO bending angle tropopause (BAT) height (BATH), and then give the comparison results between RO LRTH and corresponding RO BATH as supplement to analyse the difference between tropopause height derived from the above two methods. The results indicate that BATH show consistent 0.8&ndash;1.2&thinsp;km positive bias over tropics and high latitude region compared with LRTH, and over mid latitude region, results of BATH show less stability. Besides, the mean bias between BATH and LRTH presents different symmetrical characteristic during 2017.12&ndash;2018.2 (DJF) and 2018.6&ndash;2018.8 (JJA). However, the mean value of both LRTH and BATH show the similar tropopause variation trend, indicating the availability of both two methods.</p>