CMIP6 global cyclone tracks

This folder contains CMIP6 cyclone tracks generated for Pepler (2024) and Pepler et al. (2025). For associated reanalysis datasets see https://doi.org/10.6084/m9.figshare.24086898.v1. These cyclones were identified using the Murray and Simmonds (1991) and Simmonds et al. (1999) cyclone tracking scheme. The source code and documentation is available at https://cyclonetracker.earthsci.unimelb.edu.au/Tracks are provided for 8 CMIP6 models from historical simulations for 1950-2014, and ssp3-7.0 for 2015-2099. Surface cyclones are tracked using 6-hourly MSLP, and upper cyclones are tracked using 6-hourly 500 hPa geopotential height for models where this is available. These models were selected based on availability of 6-hourly 500hPa data on the NCI node of the ESGF.Cyclone tracks are provided based on the weakest intensity threshold, with stronger thresholds typically identified to select lows for use in the paper. For more details on the parameters used for detection and tracking see the files *incycloc and *intrack which are used as inputs for the tracking scheme.A separate track file is provided for each year, beginning on 1 December of the previous year, to allow for the identification of cross-year tracks when relevant. Each .tar.gz file includes all tracks for one simulation, e.g. $model_$member_$ssp_$level_$details.tar.gzColumn headings:ID Track IDFix Instance within trackDate Date* (UTC)Time Time (UTC)Open/closed Is there closed circulation (0) or an "open" ridge. Lon LongitudeLat LatitudeMSLP Central pressure (hPa)Laplacian Laplacian of MSLP (hPa. Deg.lat^2), which represents the curvature of the MSLP. This is a better indicator of the strength of a systemDepth Depth of cyclone (hPa) between central point and outer radiusRadius Radius of cyclone (degrees)Up Steering velocity (U)Vp Steering velocity (V)*Dates are two digit years, and in some cases are wrong because of the way the tracking scheme works (e.g. 1999-2001).References: Murray, R. J., and I. Simmonds, 1991: A numerical scheme for tracking cyclone centres from digital data. Part I: Development and operation of the scheme. Aust. Meteorol. Mag., 39, 155166.Simmonds, I., R. J. Murray, and R. M. Leighton, 1999: A refinement of cyclone tracking methods with data from FROST. Aust. Meteorol. Mag., (special edition), 3549.Pepler, Acacia (2024) Recent trends in extratropical lows and their rainfall over Australia. <i>Journal of Southern Hemisphere Earth Systems Science</i> 74, ES24002. https://doi.org/10.1071/ES24002Pepler AS, Di Virgilio G, Dowdy AD, Goyal R, Su C-H, Thatcher M, and Syktus J. (2025) Projections of Australian low pressure systems in downscaled CMIP6 models Submitted to JSHESS

本文件夹包含为Pepler(2024)及Pepler等人(2025)研究生成的CMIP6（Coupled Model Intercomparison Project Phase 6，耦合模式比较计划第六阶段）气旋轨迹数据。相关再分析数据集可参见https://doi.org/10.6084/m9.figshare.24086898.v1。
本数据集所涉及的气旋采用Murray与Simmonds(1991)以及Simmonds等人(1999)提出的气旋追踪方案识别完成。该追踪方案的源代码与文档可访问https://cyclonetracker.earthsci.unimelb.edu.au获取。
本数据集提供了8个CMIP6模式的历史模拟试验（1950-2014年）以及SSP3-7.0（Shared Socioeconomic Pathway 3-7.0，共享社会经济路径3-7.0）情景下2015-2099年的气旋轨迹数据。其中，地面气旋通过6小时分辨率的MSLP（Mean Sea Level Pressure，海平面气压）进行追踪；对于提供相关数据的模式，高空气旋则通过6小时分辨率的500 hPa位势高度场进行追踪。本研究所选用的模式需满足在ESGF（Earth System Grid Federation，地球系统网格联合会）的NCI（National Computational Infrastructure，澳大利亚国家计算基础设施）节点上可获取6小时分辨率500 hPa数据这一条件。
本数据集提供的气旋轨迹基于最弱强度阈值生成，更强的强度阈值通常用于筛选论文中所需的低压系统。如需了解检测与追踪过程中所用参数的更多细节，请参阅作为追踪方案输入文件的*incycloc与*intrack。
为便于识别跨年度气旋轨迹，我们为每个年度生成单独的轨迹文件，其起始时间为前一年的12月1日。每个.tar.gz压缩包包含单次模拟的全部轨迹数据，命名格式例如：$model_$member_$ssp_$level_$details.tar.gz。
数据列说明如下：
ID：轨迹编号
Track ID：轨迹内的实例编号
Date：日期（UTC，Coordinated Universal Time，协调世界时）
Time：时间（UTC，Coordinated Universal Time，协调世界时）
Open/closed：是否存在闭合环流，0代表闭合环流，或为“开放”脊
Lon：经度
Lat：纬度
MSLP：中心气压（单位：百帕hPa）
Laplacian：海平面气压的拉普拉斯值（单位：hPa·(°纬度)^-2），用于表征海平面气压的曲率，是表征系统强度的更优指标
Depth：气旋中心与外围半径间的气压差（单位：hPa，即气旋深度）
Radius：气旋半径（单位：度）
Up：引导气流U分量
Vp：引导气流V分量
*注：日期采用两位年份格式，部分情况下会因追踪方案的运行逻辑出现错误（例如1999-2001）。
参考文献：
1. Murray, R. J. 与 Simmonds, I., 1991: 一种从数字数据中追踪气旋中心的数值方案 第一部分：方案的开发与运行. 《澳大利亚气象杂志》, 39, 155–166.
2. Simmonds, I., Murray, R. J. 与 Leighton, R. M., 1999: 基于FROST数据的气旋追踪方法改进. 《澳大利亚气象杂志》(特刊), 35–49.
3. Pepler, Acacia, 2024: 澳大利亚温带低压系统及其降雨的近期趋势. 《南半球地球系统科学杂志》, 74, ES24002. https://doi.org/10.1071/ES24002
4. Pepler AS, Di Virgilio G, Dowdy AD, Goyal R, Su C-H, Thatcher M 与 Syktus J., 2025: 降尺度CMIP6模式中澳大利亚低压系统的投影. 提交至《南半球地球系统科学杂志》(JSHESS)

搜集汇总

背景与挑战

背景概述

该数据集提供8个CMIP6模型生成的全球气旋轨迹数据，包含历史时期(1950-2014)和未来情景(2015-2099)的追踪结果，使用MSLP和500hPa位势高度数据分别追踪地表和高空气旋，采用Murray-Simmonds追踪方案生成。