Active cloud observations from A‐Train's CloudSat and CALIPSO satellites offer new opportunities to examine the vertical structure of hydrometeor layers. We use the 2B‐CLDCLASS‐LIDAR merged CloudSat‐CALIPSO product to examine global aspects of hydrometeor vertical stratification. We group the data into major cloud vertical structure (CVS) classes based on our interpretation of how clouds in three standard atmospheric layers overlap and provide their global frequency of occurrence. The two most frequent CVS classes are single‐layer (per our definition) low and high clouds that represent ~53% of cloudy skies, followed by high clouds overlying low clouds, and vertically extensive clouds that occupy near‐contiguously a large portion of the troposphere. The prevalence of these configurations changes seasonally and geographically, between daytime and nighttime, and between continents and oceans. The radiative effects of the CVS classes reveal the major radiative warmers and coolers from the perspective of the planet as a whole, the surface, and the atmosphere. Single‐layer low clouds dominate planetary and atmospheric cooling and thermal infrared surface warming. We also investigate the consistency between passive and active views of clouds by providing the CVS breakdowns of Moderate Resolution Imaging Spectroradiometer cloud regimes for spatiotemporally coincident MODIS‐Aqua (also on the A‐Train) and CloudSat‐CALIPSO daytime observations. When the analysis is expanded for a more in‐depth look at the most heterogeneous of the MODIS cloud regimes, it ultimately confirms previous interpretations of their makeup that did not have the benefit of collocated active observations.
Coincident multiyear measurements of aerosol, cloud, precipitation, and radiation at near‐global scales are analyzed to diagnose their apparent relationships as suggestive of interactions previously proposed based on theoretical, observational, and model constructs. Specifically, we examine whether differences in aerosol loading in separate observations go along with consistently different precipitation, cloud properties, and cloud radiative effects. Our analysis uses a cloud regime (CR) framework to dissect and sort the results. The CRs come from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor and are defined as distinct groups of cloud systems with similar covariations of cloud top pressure and cloud optical thickness. Aerosol optical depth used as proxy for aerosol loading comes from two sources, MODIS observations and the MERRA‐2 reanalysis, and its variability is defined with respect to local seasonal climatologies. The choice of aerosol data set impacts our results substantially. We also find that the responses of the marine and continental component of a CR are frequently quite disparate. Overall, CRs dominated by warm clouds tend to exhibit less ambiguous signals but also have more uncertainty with regard to precipitation changes. Finally, we find weak, but occasionally systematic covariations of select meteorological indicators and aerosol, which serve as a sober reminder that ascribing changes in cloud and cloud‐affected variables solely to aerosol variations is precarious.
We employ the cloud regime concept to identify large‐scale tropical convective systems and investigate their characteristics in terms of organization and precipitation. The tropical cloud regimes (TCRs) are derived from Moderate Resolution Imaging Spectroradiometer cloud optical thickness and cloud top pressure two‐dimensional joint histograms. We focus on the TCRs that have relatively low cloud top pressures and high cloud optical thicknesses, as well as heavy precipitation, namely, TCR1 (convective core‐dominant), TCR2 (various high clouds), and TCR3 (anvils). The horizontal size of aggregates of TCR1, TCR2, or TCR3 occurrences (TCR123) is identified as the number of contiguous 1° × 1° grid cells occupied by either of these three TCRs. For the small‐ to intermediate‐size aggregates (TCR123 size 20 to 160 one‐degree grid cells), there is large variability in the fraction of the aggregate each TCR occupies, but generally, TCR2 exhibits the highest fraction. As the total system size grows, the variability shrinks and for the largest systems ratios eventually converge to 0.3, 0.2, and 0.5 for TCR1, TCR2, and TCR3, respectively. The mean precipitation of convective core‐rich TCR1 is generally high for the systems of intermediate size (80–160 one‐degree grid cells) but with the highest mean coming from smaller systems of 20–40 grid cells. For the largest systems, their mean precipitation in areas containing cores (TCR1) are relatively low with suppressed variation. The mean precipitation rates of TCR2 and TCR3 in a TCR123 aggregate tend to be stronger when accompanying TCR1 mean precipitation rate is also high.
A new organization metric was developed to quantify the degree of aggregation of tropical convective systems at synoptic scales • The new organization metric is optimized for multiple organized aggregates occupying sparsely a large and noisy domain.• The new organization metric successfully captures known synoptic convective behavior like the responses to the Madden-Julian Oscillation, and is potentially applicable to a wide range of domain sizes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.