Convective dynamics and the response of precipitation extremes to warming in radiative-convective equilibrium
Tristan H. Abbott, Timothy W. Cronin, Tom Beucler
备注：
28 pages, 15 figures, 1 table. This work has been accepted to Journal of the Atmospheric Sciences. The AMS does not guarantee that the copy provided here is an accurate copy of the final published work
Tropical precipitation extremes are expected to strengthen with warming, but quantitative estimates remain uncertain because of a poor understanding of changes in convective dynamics. This uncertainty is addressed here by analyzing idealized convection-permitting simulations of radiative-convective equilibrium in long-channel geometry. Across a wide range of climates, the thermodynamic contribution to changes in instantaneous precipitation extremes follows near-surface moisture, and the dynamic contribution is positive and small, but sensitive to domain size. The shapes of mass flux profiles associated with precipitation extremes are determined by conditional sampling that favors strong vertical motion at levels where the vertical saturation specific humidity gradient is large, and mass flux profiles collapse to a common shape across climates when plotted in a moisture-based vertical coordinate. The collapse, robust to changes in microphysics and turbulence schemes, implies a thermodynamic contribution that scales with near-surface moisture despite substantial convergence aloft and allows the dynamic contribution to be defined by the pressure velocity at a single level. Linking the simplified dynamic mode to vertical velocities from entraining plume models reveals that the small dynamic mode in channel simulations (<~2 %/K) is caused by opposing height-dependences of vertical velocity and density, together with the buffering influence of cloud-base buoyancies that vary little with surface temperature. These results reinforce an emerging picture of the response of extreme tropical precipitation rates to warming: a thermodynamic mode of about 7 %/K dominates, with a minor contribution from changes in dynamics.
Did recent sea surface temperature warming reinforce the extreme East Asian summer monsoon precipitation in 2020?
Ulsan National Institute of Science and Technology（蔚山科学技术院）；Pohang University of Science and Technology（浦项科技大学）；Yonsei University（延世大学）；Seoul National University（首尔大学）
MAG-Net: Radar-Satellite Fusion for Severe Convective Nowcasting with Matched Evaluation of Satellite Contributions
Chinese Academy of Meteorological Sciences（中国气象局）；National Meteorological Information Center（国家气象信息中心）；Xiong’an Institute of Meteorological Artificial Intelligence（雄安气象人工智能研究院）
Marine Heatwaves in the Arabian Sea: Drivers and Impacts on Atmospheric Circulation and Extreme Precipitation
University of Colorado, Boulder（科罗拉多大学博尔德分校）；Texas A&M University–Corpus Christi（德克萨斯农工大学科珀斯克里斯蒂分校）；Scripps Institution of Oceanography, University of California, San Diego（加州大学圣地亚哥分校斯克里普斯海洋研究所）；Florida State University（佛罗里达州立大学）
The forgotten role of wave dynamics in modulating the low cloud response to warm pool warming
University of Illinois Urbana Champaign（伊利诺伊大学厄巴纳-香槟分校）；Scripps Institution of Oceanography（斯克里普斯海洋研究所）；Department of Earth Sciences and Environmental Change, University of Illinois Urbana Champaign（伊利诺伊大学厄巴纳-香槟分校地球科学与环境变化系）；Department of Oceanography, School of Ocean and Earth Science and Technology (SOEST), University of Hawai‘i at Mānoa（夏威夷大学马诺阿分校海洋与地球科学技术学院海洋学系）；International Pacific Research Center (IPRC), SOEST, University of Hawai‘i at Mānoa（夏威夷大学马诺阿分校海洋与地球科学技术学院国际太平洋研究中心）
Cold pools, Breezes, and Monsoons: Propagating Convection over New Guinea
NSF National Center for Atmospheric Research（美国国家科学基金会国家大气研究中心）；University of Hawai‘i at Mānoa（夏威夷大学马诺阿分校）；International Centre for Theoretical Physics（国际理论物理中心）
Investigating the Robustness of Extreme Precipitation Super-Resolution Across Climates
Expertise Center for Climate Extremes, University of Lausanne（极端气候专家中心，洛桑大学）；Faculty of Geosciences and Environment, University of Lausanne（地球科学与环境学院，洛桑大学）；Faculty of Business and Economics (HEC), University of Lausanne（商业经济学院（HEC），洛桑大学）
A Multivariable Approach to the Regional Calibration of the Galvez Davison Index across Mexico Climate Regimes
Instituto de Astronomía y Meteorología (IAM), Departamento de Física, Centro Universitario de Ciencias Exactas e Ingenierías (CUCEI), Universidad de Guadalajara（瓜达拉哈拉大学）；Agencia Mexicana de Meteorología y Geociencias (GEOSMET)（墨西哥气象与地球科学署）；Centro de Investigaciones sobre Desertificación, Consejo Superior de Investigaciones Científicas (CIDE, CSIC-UV-GVA)（西班牙国家研究委员会沙漠化研究中心）；Unidad Académica de Estudios Territoriales Yucatán (UAETY), Instituto de Geografía, Universidad Nacional Autónoma de México (UNAM)（墨西哥国立自治大学）；Colorado State University（科罗拉多州立大学）；University of Valladolid（巴利亚多利德大学）；Agencia Estatal de Meteorología (AEMET)（西班牙国家气象局）；Complutense University of Madrid（马德里康普顿斯大学）
Transition to double-cell mock Walker circulations with surface warming explained by periodic convection
Courant Institute of Mathematical Sciences, New York University（纽约大学柯朗数学科学研究所）；Institute of Earth Sciences, The Hebrew University of Jerusalem（耶路撒冷希伯来大学地球科学学院）；Department of Geosciences, Princeton University（普林斯顿大学地质科学系）；Program in Atmospheric and Oceanic Sciences, Princeton University（普林斯顿大学大气与海洋科学项目）
Have precipitation extremes and annual totals been increasing in the world's dry regions over the last 60 years?
在过去几十年中，全球陆地大部分地区的日极端降雨量和年总降雨量都有所增加。这些观测结果与气候变暖的理论考虑是一致的。然而，直到最近，这些全球趋势还没有显示出对水分有限的陆地地区的持续影响。Donat et al.（2016，Nature气候变化，doi：10.1038/nclimate 2941）最近发表的一项研究发现，全球干旱地区日极端降雨量和年降雨总量迅速增加。在这里，我们重新评估了各自的分析，发现a）在数据标准化之前选择参考期所引入的统计伪影导致对报告趋势的高估高达40%，并且b）“全球干旱地区”的定义影响了报告的全球极端降雨汇总趋势。使用相同的观测数据集，但考虑到统计人为因素，并使用替代的、公认的干燥定义，我们发现世界干旱地区的强降水没有显著增加。适当的数据预处理方法和考虑到干旱定义的不确定性，对于量化世界干旱地区的空间汇总趋势至关重要。鉴于这一问题与许多可能受影响的利害关系方高度相关，我们呼吁谨慎考虑具体的数据处理方法，包括与干旱地区定义有关的问题，以保证所通报的气候变化相关调查结果的可靠性。
