In 1979, Herbert Riehl and Joanne Simpson (Malkus) analytically estimated that 1600–2400 undilute convective cores vertically transport energy to the tropopause at any given time within a region where upper-tropospheric energy is only exported from the tropics. The focus of this paper is to update this estimate using modern satellite observations, compare hot tower frequency and intensity characteristics to all deep convective cores that reach the upper troposphere, and document hot tower spatiotemporal variability in relation to precipitation and high cloud properties within the tropical trough zone (between 13 °S and 19 °N). Cloud vertical profiles from CloudSat and CALIPSO measurements supply convective core diameters and proxies for intensity and convective activity, and these proxies are augmented with brightness temperature data from geostationary satellite observations, precipitation information from IMERG, and cloud radiative properties from CERES. Less than 35% of all deep cores are classified as hot towers, and we estimate that 800–1700 hot towers occur at any given time over the course of a day, with the mean maximum core and hot tower frequency occurring at the time of year when peak convective intensity and precipitation occur. Convective objects that contain hot towers frequently contain multiple cores, and the largest systems with five or more distinct cores most frequently occur in regions where organized mesoscale convective systems and the highest climatological mean rain rates are known to occur. Analysis of co-located radar and infrared brightness temperatures reveals that passive observations alone are not sufficient to unambiguously distinguish hot towers using simple brightness temperature thresholds.

1979 年，Herbert Riehl 和 Joanne Simpson （Malkus） 分析估计，在对流层上部能量仅从热带输出的区域内，1600-2400 个未渗透的对流核心在任何给定时间垂直将能量输送到对流层顶。本文的重点是使用现代卫星观测更新这一估计，将热塔频率和强度特征与到达对流层上部的所有深对流核心进行比较，并记录与热带槽区（南纬 13 °C 和 19 °N 之间）内降水和高云特性相关的热塔时空变化。来自 CloudSat 和 CALIPSO 测量的云垂直剖面提供了对流核心直径和强度和对流活动的代理，这些代理还通过来自对地静止卫星观测的亮温数据、来自 IMERG 的降水信息和来自 CERES 的云辐射特性进行了增强。不到 35% 的深层核心被归类为热塔，我们估计在一天中的任何给定时间都会出现 800-1700 个热塔，平均最大核心和热塔频率发生在一年中出现峰值对流强度和降水的时间。包含热塔的对流天体通常包含多个核心，而具有五个或更多不同核心的最大系统最常出现在已知有组织的中尺度对流系统和最高气候平均降雨率的区域。对共址雷达和红外亮温的分析表明，仅靠被动观测不足以使用简单的亮温阈值明确区分热塔。