Mixed Phase Clouds

Mixed-Phase Clouds: Observations and Modeling presents advanced research topics on mixed-phase clouds. As the societal impacts of extreme weather and its forecasting grow, there is a continuous need to refine atmospheric observations, techniques and numerical models. Understanding the role of clouds in the atmosphere is increasingly vital for current applications, such as prediction and prevention of aircraft icing, weather modification, and the assessment of the effects of cloud phase partition in climate models. This book provides the essential information needed to address these problems with a focus on current observations, simulations and applications. Provides in-depth knowledge and simulation of mixed-phase clouds over many regions of Earth, explaining their role in weather and climate Features current research examples and case studies, including those on advanced research methods from authors with experience in both academia and the industry Discusses the latest advances in this subject area, providing the reader with access to best practices for remote sensing and numerical modeling

"Ice crystals, with their myriad shapes, sizes and densities, play an important role in the formation, evolution and subsequent impact of ice and mixed-phase clouds on weather and climate. There are numerous pathways through which ice crystals nucleate, grow and dissipate. Although many of these are understood theoretically and have been simulated in the laboratory and cloud chambers, they are less well documented in natural clouds. The challenges of making measurements from moving platforms in an environment that is spatially inhomogenous and temporally unsteady, as well as sometimes at high altitudes and in clouds with icing potential makes these clouds difficult to observe. Nevertheless, the importance of ice clouds on climate and the hydrological cycle compels us to better understand ice processes through improved measurements over as broad of a temporal and geographical scale as possible. This monograph represents a collection of articles that do exactly that."-- Book jacket.

Provides a comprehensive analysis of modern theories of cloud microphysical processes and their representation in numerical cloud models.

Clouds affect our daily weather and play key roles in the global climate. Through their ability to precipitate, clouds provide virtually all of the fresh water on Earth and are a crucial link in the hydrologic cycle. With ever-increasing importance being placed on quantifiable predictions - from forecasting the local weather to anticipating climate change - we must understand how clouds operate in the real atmosphere, where interactions with natural and anthropogenic pollutants are common. This textbook provides students - whether seasoned or new to the atmospheric sciences - with a quantitative yet approachable path to learning the inner workings of clouds. Developed over many years of the authors' teaching at Pennsylvania State University, Physics and Chemistry of Clouds is an invaluable textbook for advanced students in atmospheric science, meteorology, environmental sciences/engineering and atmospheric chemistry. It is also a very useful reference text for researchers and professionals.

This work provides new insights into macro- and microphysical properties of Arctic mixed-phase clouds: first, by comparing semi-idealized large eddy simulations with observations; second, by dissecting the influences of different surface types and boundary layer structures on Arctic mixed- phase clouds; third, by elucidating the dissipation process; and finally by analyzing the main microphysical processes inside Arctic mixed-phase clouds. This work was published by Saint Philip Street Press pursuant to a Creative Commons license permitting commercial use. All rights not granted by the work's license are retained by the author or authors.

Airborne measurements of six mid-level clouds observed over the Great Plains of the United States in late 1999 and early 2000 are analyzed extensively. All cloud fields are associated with a 500-mb low-pressure center or a potential vorticity maximum, with additional lift provided by upper-level jet streams. Data show that these innocuous looking clouds display complicated microphysical and thermodynamic structures. Five of six cases include mixed- phase conditions in temperatures ranging from near freezing to -3l C, at altitudes of 2400 to 7200 m. Four of the cases consist of a single cloud layer, while the other two are multi-layered systems. Of particular note, in single- layered clouds, there is an increase of liquid water content with height versus a decrease in ice water content over the same depth. This is in contrast to multi-layered systems, where the liquid water content has the same basic shape, but the ice water content is distributed more uniformly throughout all layers. We attribute these structural differences to a seeder-feeder mechanism operating in the multi-layered systems. A lack of temperature inversions in these mid- level clouds is a major difference from the thermodynamic structure of most stratocumulus systems. We found the virtual potential temperature to be the best discriminator of cloud interfaces for mid-level clouds, with 1-2 C differences between ambient and cloud air. A noteworthy contribution to this observational study was the use of the Cloud Particle Imager (CPI) instrument for the qualitative analysis of the particle sizes, shapes, habits, and distributions through the cloud. An analysis of the liquid water budget of a Lagrangian cloud sample revealed that large-scale subsidence was the main mechanism responsible for its dissipation. Heating rates and fluxes are computed for each cloud using a single-column radiative transfer model. OBSERVED MICROPHYSICAL AND RADIATIVE STRUCTURE OF MID-LEVEL, MIXED-PHASE CLOUDS

This book focuses specifically on bin and bulk parameterizations for the prediction of cloud and precipitation at various scales - the cloud scale, mesoscale, synoptic scale, and the global climate scale. It provides a background to the fundamental principles of parameterization physics, including processes involved in the production of clouds, ice particles, liquid water, snow aggregate, graupel and hail. It presents full derivations of the parameterizations, allowing readers to build parameterization packages, with varying levels of complexity based on information in the book. Architectures for a range of dynamical models are given, in which parameterizations form a significant tool for investigating large non-linear numerical systems. Model codes are available online at www.cambridge.org/9780521883382. Written for researchers and advanced students of cloud and precipitation microphysics, this book is also a valuable reference for all atmospheric scientists involved in models of numerical weather prediction.