Variability of the Polar Stratosphere and Its Influence on Surface Weather and Climate - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Variability of the Polar Stratosphere and Its Influence on Surface Weather and Climate write by William J. M. Seviour. This book was released on 2014. Variability of the Polar Stratosphere and Its Influence on Surface Weather and Climate available in PDF, EPUB and Kindle.
Variability of the Polar Stratospheric Vortex and Its Impact on Surface Climate Patterns
Variability of the Polar Stratospheric Vortex and Its Impact on Surface Climate Patterns - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Variability of the Polar Stratospheric Vortex and Its Impact on Surface Climate Patterns write by Aditi Sheshadri. This book was released on 2015. Variability of the Polar Stratospheric Vortex and Its Impact on Surface Climate Patterns available in PDF, EPUB and Kindle. This thesis investigates various aspects of the variability of the stratospheric polar vortex and the effect of this variability on tropospheric weather and climate patterns on various timescales. In the first part of this work, an improved idealized model was developed to study the coupled stratosphere-troposphere system. The model is forced by relaxation to a specified equilibrium temperature profile, which varies seasonally only in the stratosphere. This model setup permits the investigation of stratosphere-troposphere interactions on seasonal timescales, without the complication of an internal tropospheric seasonal cycle. The model is forced with different shapes and amplitudes of simple bottom topography, resulting in a range of stratospheric climates. The effect of these different kinds of topography on the seasonal variability of the strength of the polar vortex, the average timing and variability in timing of the final breakup of the vortex (final warming events), the conditions of occurrence and frequency of midwinter warming events, and the impact of the stratospheric seasonal cycle on the troposphere are explored. The inclusion of wavenumber 1 and wavenumber 2 topographies results in very different stratospheric seasonal variability. Hemispheric differences in stratospheric seasonal variability are recovered in the model with appropriate choices of wave-2 topography. In the model experiment with a realistic Northern Hemisphere-like frequency of midwinter warming events, the distribution of the intervals between these events suggest that the model has no year to year memory. When forced with wave-1 topography, the gross features of seasonal variability are similar to those forced with wave-2 topography, but the dependence on forcing magnitude is weaker. Further, the frequency of major warming events has a non-monotonic dependence on forcing magnitude, and never reaches the frequency observed in the northern hemisphere. In the second part of the thesis, the impact of stratospheric ozone depletion on the Antarctic polar vortex and its subsequent influences on southern hemisphere surface climate patterns is investigated. It is verified that stratospheric final warming events have an impact on tropospheric circulation in a simplified GCM with seasonal variations in the stratosphere only. The model produces qualitatively realistic final warming events whose influence extends down to the surface, much like what has been reported in observational analyses. The hypothesis that recent observed trends in surface westerlies in the Southern Hemisphere are directly consequent on observed trends in the timing of stratospheric final warming events is tested. It is confirmed that there is a statistically significant shift towards later final warming events in the years with large ozone depletion. However it is found that the observed trends in surface westerlies cannot be attributed simply to this shift towards later final warming events. Finally, responses of the idealized AGCM to polar stratospheric cooling that mimics the radiative effects of stratospheric ozone depletion are studied. It is found that there are two factors that play a role in setting the magnitude and persistence of the model's surface response to cooling: the seasonal cycle of tropospheric annular mode timescales, and whether or not the imposed cooling leads to the presence of stratospheric westerlies at a time when easterlies were prevalent in the control run. That is, the surface response is sensitive to the timing of the imposed polar stratospheric cooling.
Stratosphere Troposphere Interactions
Stratosphere Troposphere Interactions - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Stratosphere Troposphere Interactions write by K. Mohanakumar. This book was released on 2008-07-03. Stratosphere Troposphere Interactions available in PDF, EPUB and Kindle. Stratospheric processes play a signi?cant role in regulating the weather and c- mate of the Earth system. Solar radiation, which is the primary source of energy for the tropospheric weather systems, is absorbed by ozone when it passes through the stratosphere, thereby modulating the solar-forcing energy reaching into the t- posphere. The concentrations of the radiatively sensitive greenhouse gases present in the lower atmosphere, such as water vapor, carbon dioxide, and ozone, control the radiation balance of the atmosphere by the two-way interaction between the stratosphere and troposphere. The stratosphere is the transition region which interacts with the weather s- tems in the lower atmosphere and the richly ionized upper atmosphere. Therefore, this part of the atmosphere provides a long list of challenging scienti?c problems of basic nature involving its thermal structure, energetics, composition, dynamics, chemistry, and modeling. The lower stratosphere is very much linked dynamically, radiatively,and chemically with the upper troposphere,even though the temperature characteristics of these regions are different. The stratosphere is a region of high stability, rich in ozone and poor in water - por and temperature increases with altitude. The lower stratospheric ozone absorbs the harmful ultraviolet (UV) radiation from the sun and protects life on the Earth. On the other hand, the troposphere has high concentrations of water vapor, is low in ozone, and temperature decreases with altitude. The convective activity is more in the troposphere than in the stratosphere.
The Stratosphere and Its Role in the Climate System
The Stratosphere and Its Role in the Climate System - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook The Stratosphere and Its Role in the Climate System write by Guy P. Brasseur. This book was released on 2013-06-29. The Stratosphere and Its Role in the Climate System available in PDF, EPUB and Kindle. This book presents a summary of the lectures given at the NATO Advanced Science Institute (ASI) which took place at Val Morin, Quebec, Canada, 4-15 September, 1995. This summer school offered an excellent opportunity to discuss key scientific questions related to the stratosphere and its importance for the climate system. Approximately 85 students and 15 lecturers from 19 nations attended the ASI which was sponsored by SPARC (Stratospheric Processes and Their Role in Climate), a project of the World Climate Research Programme. The purpose of the ASI was to present truly tutorial lectures rather than highly specialized or technical talks. At the conference, mornings were devoted to fundamental presentations while short illustrative talks were given in the afternoon. The book presents a summary of the two types of lectures. We were fortunate to enlist the participation of outstanding experts in the field of atmospheric science and excellent teachers. Students were strongly encouraged to actively participate in various activities during the summer school; for example, the students were asked to summarize the lectures given by the teachers, and in most cases, the chapters presented in this book were written by small groups of students and reviewed by the lecturers. During the school, students had also the opportunity to present posters that described their personal research. These lecture notes are divided into three major parts.
Middle Atmosphere Dynamics
Middle Atmosphere Dynamics - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Middle Atmosphere Dynamics write by David G. Andrews. This book was released on 2016-07-21. Middle Atmosphere Dynamics available in PDF, EPUB and Kindle. For advanced undergraduate and beginning graduate students in atmospheric, oceanic, and climate science, Atmosphere, Ocean and Climate Dynamics is an introductory textbook on the circulations of the atmosphere and ocean and their interaction, with an emphasis on global scales. It will give students a good grasp of what the atmosphere and oceans look like on the large-scale and why they look that way. The role of the oceans in climate and paleoclimate is also discussed. The combination of observations, theory and accompanying illustrative laboratory experiments sets this text apart by making it accessible to students with no prior training in meteorology or oceanography. * Written at a mathematical level that is appealing for undergraduates and beginning graduate students * Provides a useful educational tool through a combination of observations and laboratory demonstrations which can be viewed over the web * Contains instructions on how to reproduce the simple but informative laboratory experiments * Includes copious problems (with sample answers) to help students learn the material.
