Central Arctic weather forecasting: Confronting the ECMWF IFS with observations from the Arctic Ocean 2018 expedition
Central Arctic weather forecasting: Confronting the ECMWF IFS with observations from the Arctic Ocean 2018 expedition
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中北极天气预报：用 ECMWF IFS 与 2018 年北冰洋考察的观测结果进行对比
DOI：
10.1002/qj.3971
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发表时间：
2021
影响因子：
8.9
通讯作者：
Tjernström M
中科院分区：
文献类型：
--
作者：
Tjernström M
欧洲中期天气预报中心的数值天气预报模型的预报使用瑞典破冰船奥登号上北冰洋2018年探险队的大量观测结果进行评估。大气模型（Cy 45 r1）与ERA 5再分析（Cy 41 r2）所用的大气模型相似。评估为期1个月，破冰船停泊在北极附近的浮冰上;每天发布4次，共使用125次预报。同化了标准的地面观测和6小时一次的探测，以确保初始模型误差较小。模型误差可以分为两组。首先，与动态相关的变量具有随预测长度而增长的误差;误差扩散也随时间而增长。初始误差很小，有利于第二组热力学变量的稳健评估。这些特征为6-12小时的快速误差增长，之后误差饱和;误差扩散大致恒定。模型中的地表和近地表气温都太高。在夏季，尽管正在融化，但两者通常都在零度以上;然而，随着表面冻结，温暖的偏差会增加。偏暖是由于大气太暖;地表感热通量的误差将额外的热量从大气传递到地表。低对流层温度误差有一个明显的垂直结构：在最低的几个100米和一个大的冷偏差1公里左右的大暖偏差，这种结构具有显着的昼夜循环，并紧密耦合到模拟云的错误。云出现得太频繁，而且在低层大气中的云层太深;最低层的云基本上永远不会破裂。云存在的最大误差与大约1公里处的最大冷偏差一致。
Forecasts with the European Centre for Medium‐Range Weather Forecasts' numerical weather prediction model are evaluated using an extensive set of observations from the Arctic Ocean 2018 expedition on the Swedish icebreakerOden. The atmospheric model (Cy45r1) is similar to that used for the ERA5 reanalysis (Cy41r2). The evaluation covers 1 month, with the icebreaker moored to drifting sea ice near the North Pole; a total of 125 forecasts issued four times per day were used. Standard surface observations and 6‐hourly soundings were assimilated to ensure that the initial model error is small. Model errors can be divided into two groups. First, variables related to dynamics feature errors that grow with forecast length; error spread also grows with time. Initial errors are small, facilitating a robust evaluation of the second group; thermodynamic variables. These feature fast error growth for 6–12 hr, after which errors saturates; error spread is roughly constant. Both surface and near‐surface air temperatures are too warm in the model. During the summer both are typically above zero in spite of the ongoing melt; however, the warm bias increases as the surface freezes. The warm bias is due to a too warm atmosphere; errors in surface sensible heat flux transfer additional heat from the atmosphere to the surface. The lower troposphere temperature error has a distinct vertical structure: a substantial warm bias in the lowest few 100 m and a large cold bias around 1 km; this structure features a significant diurnal cycle and is tightly coupled to errors in the modelled clouds. Clouds appear too often and in a too deep layer of the lower atmosphere; the lowest clouds essentially never break up. The largest error in cloud presence is aligned with the largest cold bias at around 1 km.
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通过观测对抗区域气候模型中的北极对流层、云和地表能源预算表示
DOI：
10.1029/2019jd031783
发表时间：
2020
期刊：
Journal of Geophysical Research: Atmospheres
影响因子：
--
作者：
J. Sedlar;M. Tjernström;A. Rinke;A. Orr;J. Cassano;X. Fettweis;G. Heinemann;M. Seefeldt;A. Solomon;H. Matthes;T. Phillips;S. Webster
通讯作者：
S. Webster
北极夏季云海研究（ASCOS）期间北极中部夏季的气象条件
影响因子：
6.3
作者：
M. Tjernström;C. Birch;I. Brooks;M. Shupe;P. Persson;J. Sedlar;T. Mauritsen;C. Leck;J. Paatero;M. Szczodrak;C. Wheeler
通讯作者：
C. Wheeler
“北极边界层建模：使用示巴项目数据对六个 Arcmip 区域规模模型进行评估”
DOI：
--
发表时间：
2005
期刊：
影响因子：
--
作者：
M. Tjernström;M. Žagar;G. Svensson;J. Cassano;S. Pfeifer;A. Rinke;K. Wyser;K. Dethloff;Colin G. Jones;T. Semmler;M. Shaw
通讯作者：
M. Shaw
2018年北冰洋考察期间的气象和云状况
影响因子：
6.3
作者：
J. Vüllers;P. Achtert;I. Brooks;M. Tjernström;J. Prytherch;Annika Burzik;R. Neely III
通讯作者：
R. Neely III
北极夏季云层边界层是否存在昼夜循环？
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
M. Tjernström
通讯作者：
M. Tjernström