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2018 | Buch

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Climate Variability and Sunspot Activity

Analysis of the Solar Influence on Climate

verfasst von: Dr. Indrani Roy

Verlag: Springer International Publishing

Buchreihe : Springer Atmospheric Sciences

Enthalten in: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik"

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Über dieses Buch

This book promotes a better understanding of the role of the sun on natural climate variability. It is a comprehensive reference book that appeals to an academic audience at the graduate, post-graduate and PhD level and can be used for lectures in climatology, environmental studies and geography.

This work is the collection of lecture notes as well as synthesized analyses of published papers on the described subjects. It comprises 18 chapters and is divided into three parts: Part I discusses general circulation, climate variability, stratosphere-troposphere coupling and various teleconnections. Part II mainly explores the area of different solar influences on climate. It also discusses various oceanic features and describes ocean-atmosphere coupling. But, without prior knowledge of other important influences on the earth’s climate, the understanding of the actual role of the sun remains incomplete. Hence, Part III covers burning issues such as greenhouse gas warming, volcanic influences, ozone depletion in the stratosphere, Arctic and Antarctic sea ice, etc. At the end of the book, there are few questions and exercises for students. This book is based on the lecture series that was delivered at the University of Oulu, Finland as part of M.Sc./ PhD module.

Inhaltsverzeichnis

Frontmatter

Climatology, General Circulation, Climate Variability and Stratosphere-Troposphere Coupling

Frontmatter

Chapter 1. Climatology and General Circulation

Abstract

This chapter focused on basic definitions of climatology and general circulation. There was a discussion on climatology of sea level pressure (SLP) and sea surface temperature (SST) which was followed by defining north-south Hadley and east-west Walker circulation. It also defined and described Ferrel cell, Polar cell and various jets. It explained thermal-wind balance relationship and its relevance to jet formation.

Indrani Roy

Chapter 2. Major Modes of Variability

Abstract

This chapter focused on major modes of variability which serve the key role in controlling the regional climate. In terms of tropospheric variability, it defined and discussed ENSO (El Niño Southern Oscillation), NAO (North Atlantic Oscillation), AO and AAO (Arctic Oscillation, Antarctic Oscillation), Indian Monsoon, Indian Ocean Dipole (IOD), PDO (Pacific Decadal Oscillation) and AMO (Atlantic Multidecadal Oscillation). Later it attended stratosphere variability; this constitutes QBO (quasi-biennial oscillation) and SSW (stratospheric sudden warming). Main characteristic features of each of these modes were elaborately discussed.

Indrani Roy

Chapter 3. Stratosphere-Troposphere Coupling

Abstract

This chapter discusses stratosphere-troposphere coupling starting from a very basic background knowledge. Later it focused on the individual role of the Sun and QBO to regulate such coupling. It explores Holton-Tan effect. The combined influence of the Sun and QBO to regulate upper stratospheric polar temperature was also attended. The role of polar annular modes was described that communicate such signal down to the troposphere. Various other routes are also discussed to show how upper stratospheric solar signature from the polar vortex could be transported downward and affect tropospheric climate.

Indrani Roy

Chapter 4. Teleconnection Among Various Modes

Abstract

This chapter discusses various teleconnections involving climate modes. First, it focuses different teleconnections involving polar vortex, QBO and ENSO; later the discussion was extended up to troposphere. The ENSO being one of the major tropospheric variabilities, the subsequent discussion covered various characteristic features of ENSO and subsequently ENSO-related teleconnections. The topics covered are ENSO and jet, influence of ENSO around the world, ENSO and ISM and various types of ENSO including central Pacific (CP) type (or Modoki ENSO) and east Pacific (EP) type (or canonical ENSO). Specific influences of these two types of ENSO are also attended in details.

Indrani Roy

Chapter 5. Solar Influence Around Various Places: Robust Solar Signal on Climate

Abstract

This chapter focused on the detected robust solar signal on climate. It presented some observational results that identified solar signature on sea level pressure (SLP), sea surface temperature (SST) and annual mean air temperature. A technique of Multiple Linear Regression (MLR) methods was discussed, and a detected significant signal on SLP around Aleutian Low (AL) was analysed. A solar signal was observed around AL and Pacific High also using other techniques. In terms of SST, the region of tropical Pacific was addressed. One study noted an in-phase relationship between the Sun and tropical Pacific SST, and another study even observed a phase locking between those. A widely debated study that used the method of solar maximum compositing on tropical Pacific SST was presented discussing the methodology.

Indrani Roy

Chapter 6. Total Solar Irradiance (TSI): Measurements and Reconstructions

Abstract

This chapter focuses on total solar irradiance (TSI). It gives a very brief idea about their measurements and reconstructions. It also discussed different TSI, e.g. Solanki and Krivova, Foster and Hoyt and Schatten.

Indrani Roy

Atmosphere-Ocean Coupling and Solar Variability

Frontmatter

Chapter 7. Ocean Coupling

Abstract

This chapter initially focuses on the ocean and discusses various relevant definitions. Section 7.1 discusses shallow overturning circulation, ocean conveyor belt and global wind-driven ocean circulation. Section 7.2 describes ENSO, and focus is on various issues: (i) ENSO, thermocline and upper ocean heat content, (ii) ENSO and delayed oscillator theory, (iii) ENSO and shallow MOC in tropical Pacific and (iv) pycnocline convergence vs. Nino region sea surface temperature (SST).

Indrani Roy

Chapter 8. The Sun and ENSO Connection–Contradictions and Reconciliations

Abstract

This chapter focuses on solar signal and ENSO connection (if any) in recent centuries. The discussion begins with two contradictory findings: Contradiction (I), solar signal on tropical Pacific SST-active solar years and ENSO and Contradiction (II), solar signal on tropical Pacific SST – El Niño or La Niña. It reconciled those contradictions and additionally proposed two different mechanisms. The mechanisms differ in the earlier period to that from the later.

Indrani Roy

Chapter 9. A Debate: The Sun and the QBO

Abstract

This chapter initially discussed results of data analysis on solar and QBO separately. It is followed by a discussion on two very popular research relating to the combined influence of the Sun and QBO on the upper polar stratosphere. It reconciled why these two studies differ with each other at a certain point. Later the combined effect of the Sun and QBO was investigated on surface climate. The knowledge can be used for improving prediction skill in the polar region.

Indrani Roy

Chapter 10. Solar Influence: ‘Top Down’ vs. ‘Bottom Up’

Abstract

Two fundamentally different routes have been proposed for a solar influence on the troposphere: the first is the ‘bottom-up’ and the other the ‘top-down’ mechanism. In the ‘bottom-up’ pathway, the Sun can directly influence sea surface temperature (SST) without stratospheric feedback, whereas the ‘top-down’ solar influence is generated through the stratosphere without any influence from oceans. Those two routes are discussed in details with relevant supporting studies.

Indrani Roy

Chapter 11. An Overview of Solar Influence on Climate

Abstract

An overview of the processes shown in determining the influence of the sun on climate is formulated in a holistic way and presented in the form of a flow chart, focusing on the Pacific region. It discussed hypotheses and evidence relating the combined influences of the Quasi-Biennial Oscillation, the El Niño–Southern Oscillation, and the solar cycle on the Walker and Hadley circulations in the context of ocean–atmosphere coupling. It suggests, in that coupling, that the Sun plays an important role, but it appears to be disturbed around the final half of the last century, probably related to climate change. This study leads towards a better understanding of the system of ocean–atmosphere coupling, accounting the variability of solar cyclic and will be useful for improved understanding of the climate–sun connection.

Indrani Roy

Other Major Influences on Climate

Frontmatter

Chapter 12. Sun: Atmosphere-Ocean Coupling – Possible Limitations

Abstract

This chapter covers possible limitations in relevant analyses of atmosphere-ocean coupling initiated by the Sun. First, it focused on one study that discussed solar ‘top-down’ vs. ‘bottom-up’ mechanism. Then it addressed some limitations related to methodology and discussed solar peak year compositing method. Solar NAO connection as captured by multiple linear regression was also attended. It also discussed the solar lag relationship. At the end, years of various phases of PDO and AMO are compared, and their relevance was discussed relating to global climate.

Indrani Roy

Chapter 13. The Arctic and Antarctic Sea Ice

Abstract

This chapter covered Arctic and Antarctic climate. It discussed Arctic warming and focused on various related areas including Arctic Sea ice – last few years and recent decline. Recent behaviour of Antarctic Sea ice was also addressed.

Indrani Roy

Chapter 14. CMIP5 Project and Some Results

Abstract

This chapter focused on Coupled Model Intercomparison Project, Phase 5 (CMIP5), and discussed various results. Starting from outlining very basic equations of global climate models (GCMs) as used in CMIP5 models, it described briefly about the aim and objective of the CMIP5 project. It is followed by discussion on various experiments, historical and RCP (Representative Concentration Pathway) situation. The global temperature generated using CMIP5 models was compared with observation. Indian Summer Monsoon and El Niño Southern Oscillation in CMIP5 models were analysed in the historical and RCP situation, and few areas of agreement and disagreement were discussed. Few results from the atmospheric version of CMIP5 models (AMIP5) and Phase 3 of CMIP5 experiments (CMIP3) were also presented. Some stratospheric features are shown well captured by models.

Indrani Roy

Chapter 15. Green House Gas Warming

Abstract

This chapter focused on greenhouse effect and covered various relevant areas. Starting from laws of radiation, it included discussion on solar radiation vs. terrestrial radiation, atmospheric windows for terrestrial radiation, water vapour and carbon dioxide (CO₂) as greenhouse gases, radiative forcing and global energy balance, etc.

Indrani Roy

Chapter 16. Volcanic Influences

Abstract

Volcano causes major changes in the Earth’s atmosphere, and hence this chapter covers various influences it inflicts to the climate of Earth that involve both the stratosphere and troposphere. The different time scales of influence are also covered. Names of major volcanos in the last 250 years are mentioned. Few other areas also addressed are polar warming associated with large eruption and the combined influence of the Sun, volcano and ENSO.

Indrani Roy

Chapter 17. Ozone Depletion in the Stratosphere

Abstract

This chapter discusses Antarctic ozone hole and its relevance to banning of CFCs through Montreal Protocol. It describes that ozone in the stratosphere and greenhouse gas in the troposphere both have a comparable effect on surface climate, though ozone is more important in higher latitudes and altitudes.

Indrani Roy

Chapter 18. Influence of Various Other Solar Outputs

Abstract

Apart from solar 11-year cyclic variability, other solar outputs are also important in modulating the climate of the Earth and discussed briefly in this chapter. It discussed various routes through which solar variability may influence the climate of the lower atmosphere. At the end, there are also brief discussions on galactic cosmic ray.

Indrani Roy

Backmatter

Titel: Climate Variability and Sunspot Activity
verfasst von: Dr. Indrani Roy
Verlag: Springer International Publishing
Electronic ISBN: 978-3-319-77107-6
Print ISBN: 978-3-319-77106-9
DOI: https://doi.org/10.1007/978-3-319-77107-6