Air Sea Interaction Over The Southern Ocean On The Role Of Extratropical Cyclones Fronts And Cold Air Outbreaks

Tropical and Extratropical Air-Sea Interactions: Modes of Climate Variations provides a thorough introduction to global atmospheric and oceanic processes, as well as tropical, subtropical and mid-latitude ocean-atmosphere interactions. Written by leading experts in the field, each chapter is dedicated to a specific topic of air-sea interactions (such as ENSO, IOD, Atlantic Nino, ENSO Modoki, and newly discovered coastal Niños/Niñas) and their teleconnections. As the first book to cover all topics of tropical and extra-tropical air-sea interactions and new modes of climate variations, this book is an excellent resource for researchers and students of ocean, atmospheric and climate sciences. Presents case studies on the ocean-atmosphere phenomena, including El Nino Southern Oscillation (ENSO), Indian Ocean Dipole and different Nino/Nina phenomena Provides a clear description of air-sea relationships across the world’s ocean with an analysis of air-sea relations in different time scales and a focus on climate change Includes prospects for air-sea interaction research, thus benefiting young researchers and students

" ... as soon as one has traversed the greater part of the wild sea, one comes upon such a huge quantity of ice that nowhere in the whole world has the like been known." "This ice is of a wonderful nature. It lies at times quite still, as one would expect, with openings or large fjords in it; but sometimes its movement is so strong and rapid as to equal that of a ship running before the wind, and it drifts against the wind as often as with it." Kongespeilet - 1250 A.D. ("The Mirror of Kings") Modern societies require increasing amounts influence on the water mass and on the resulting of scientific information about the environment total environment of the region; therefore, cer tain of its characteristics will necessarily be in whieh they live and work. For the seas this information must describe the air above the sea, included.

Scientists investigating the interaction between the ocean and the atmosphere now believe that the drag coefficient, and the coefficients of heat transfer and moisture transfer at the sea surface, all increase with an intensification of the wind, reaching high values during a storm. This belief is based on the results of gradient and eddy correlation measurements in the air layer over the water, as weIl as on data concerning the effect of storms on the structure of the upper layer of the ocean and on the planetary atmospheric boundary layer. However, until recently it was impossible to explain just how the above coefficients depend on the wind velocity and to extrapolate this dependence into the region of hurricane velocities. Only by studying nonturbulent mechanisms of transfer, which play an important role dose to the surface of a stormy sea, and mechanisms of spray mediated transfer in particular, was it possible to proceed to a solution of this problem. This book presents the results of laboratory and field studies of the spray field in the air layer above the surface of a stormy sea. Since there is a dose correlation between the generation of spray and the breaking of wind waves, considerable attention is given to the analysis of data on the sea state during a storm. Su'ch data are of interest when solving a number of diverse theoretical and applied problems.

This book is composed of 12 review papers invited for the Palmen Memorial Symposium on Extratropical Cyclones held in Helsinki, Finland, 29 August - 2 September 1988. To celebrate the 90th anniversary of the birth of Professor Erik Palmén, this symposium was organized to give a state-of-the-art picture of research on the structure and dynamics of extratropical cyclones, a topic which Palmén pioneered during the era of advances in aerological analysis. This symposium was organized by the Geophysical Society of Finland and the American Meteorological Society in cooperation with the Danish, Norwegian and Swedish Geophysical Societies. Extratropical Cyclones offers state-of-the-art information on extratropical cyclones, and recent findings by European and American authorities in various subject areas. The first two chapters discuss Palmen's works on cyclones and his early general circulation concepts. The ten chapters following chronicle the advances in understanding cyclones; the theory, structure, and physical processes of cyclones; orographic cyclogenesis; and more. Extratropical Cyclones also contains synoptic case analyses, modeling results, examples of the phenomena discussed, and abundant references. While particular aspects are emphasized in the individual contributions, the book as a whole summarizes the major features of various kinds of extratropical cyclones based on observational analyses, theory and numerical experimentation. This volume is of interest to researchers in dynamic and synoptic meteorology, climatology and mesometeorology, as well as in numerical modeling and weather forecasting. It is also useful for meteorology courses at graduate and upper undergraduate levels.

Intensity and intensity change remain one of the most significant challenges in tropical cyclone (TC) prediction. Instantaneous intensity and its evolution result from complex storm-environment interactions and internal structure changes across multiple time and spatial scales. These interactions truly couple the TC to the ocean as well as the ambient environment, however have been insufficiently observed and are difficult to model. Many earlier studies have demonstrated the impact of air-sea coupling to TC intensity, as well as the physical processes involved in the ocean response to TC passage. More recent work however has shown air-sea coupling affects both structure and intensity. Hurricane Ophelia in 2005 was well -- observed by research reconnaissance aircraft during the fortuitous Hurricane Rainband and Intensity Change Experiment (RAINEX) field campaign. This mission included unprecedented airborne Doppler radar and dropsonde sampling of internal inner-core and rainband structures. These observations, supplemented by satellite, buoy, and analysis products captured a unique structural evolution in Ophelia that involved the collapse and recovery of its inner core. This thesis will investigate the structure and intensity changes that occurred in Hurricane Ophelia as a result of air-sea interaction, with particular focus on the impact of interactive ocean coupling and structure changes. Additionally, based on observations of double-eyewalllike structure during part of Ophelia's life cycle we will examine the intensity changes to address a possible interrupted or incipient eyewall replacement cycle (EWRC). A highresolution, coupled atmosphere-ocean (AO) numerical model (UWIN-CM) simulation initialized with vortex-following nested grids and global analysis fields correctly captured the inner eyewall collapse, discrete outer secondary rainband/eyewall, and recovery of distinct eyewall and rainband features as well as more appropriately simulating the true storm intensity. Model output will be used to evaluate the structure and intensity changes between uncoupled (atmosphere-only) and coupled simulations, and then focus more closely on air-sea interaction instigating changes in air-sea enthalpy flux. Good agreement between RAINEX observations and the coupled model simulation allowed for detailed analysis of the role of air-sea interaction. Without an interactive ocean, the uncoupled TC is too strong and the lack of coupling prohibits feedbacks and air-sea interactions that modify air-sea enthalpy flux and ultimately storm structure and intensity. The presence of an interactive ocean is also critical to producing the observed induced cold pool and its distribution relative to TC wind stress. The TC surface circulation feedback on the ocean was found to be important for locally modifying air-sea enthalpy flux in the inner core via upper ocean cooling, while also being important to air-sea enthalpy flux distribution when Ophelia's circulation becomes large after interacting with the cold pool. Advection of high enthalpy air at distant radii and lower enthalpy air from over the cold pool in the inner core region helped to support (suppress) convection far from (near) the storm center during the expansion, particularly a discrete outer rainband that may have served as a secondary eyewall. Finally, it should be noted that even the coupled simulation overestimates wind and precipitation intensity and initial SST, highlighting the outstanding challenge of model initial condition errors and appropriate parameterizations for convection and air-sea interaction physical processes in the complex TC-atmosphere-ocean environment.