CLIMATE VARIABILITY – SOME ASPECTS, CHALLENGES AND PROSPECTS Edited by Abdel Hannachi Climate Variability – Some Aspects, Challenges and Prospects Edited by Abdel Hannachi Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2011 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work. Any republication, referencing or personal use of the work must explicitly identify the original source. As for readers, this license allows users to download, copy and build upon published chapters even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book. Publishing Process Manager Oliver Kurelic Technical Editor Teodora Smiljanic Cover Designer InTech Design Team First published December, 2011 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from orders@intechweb.org Climate Variability – Some Aspects, Challenges and Prospects, Edited by Abdel Hannachi p. cm. ISBN 978-953-307-699-7 free online editions of InTech Books and Journals can be found at www.intechopen.com Contents Preface IX Part 1 Atmospheric Variability 1 Chapter 1 Atmospheric Low Frequency Variability: The Examples of the North Atlantic and the Indian Monsoon 3 Abdel Hannachi, Tim Woollings and Andy Turner Chapter 2 Impact of Atmospheric Variability on Soil Moisture-Precipitation Coupling 17 Jiangfeng Wei, Paul A. Dirmeyer, Zhichang Guo and Li Zhang Part 2 Climate and Solar Activity 37 Chapter 3 Solar Activity, Space Weather and the Earth’s Climate 39 Maxim Ogurtsov, Markus Lindholm and Risto Jalkanen Part 3 Climate and ENSO 73 Chapter 4 Assimilating Ocean Observation Data for ENSO Monitoring and Forecasting 75 Yosuke Fujii, Masafumi Kamachi, Toshiyuki Nakaegawa, Tamaki Yasuda, Goro Yamanaka, Takahiro Toyoda, Kentaro Ando and Satoshi Matsumoto Chapter 5 ENSO-Type Wind Stress Field Influence over Global Ocean Volume and Heat Transports 99 Luiz Paulo de Freitas Assad Part 4 Rainfall and Drought Assessment 121 Chapter 6 Drought Assessment in a Changing Climate 123 Isabella Bordi and Alfonso Sutera Chapter 7 Seasonal Summer Rainfall Prediction in Bermejo River Basin in Argentina 141 Marcela H. González and Ana María Murgida VI Contents Part 5 Adaptation Issues and Climate Variability and Change 161 Chapter 8 Climate Change Adaptation in Developing Countries: Beyond Rhetoric 163 Aondover Tarhule Chapter 9 Adapting Agriculture to Climate Variability and Change: Capacity Building Through Technological Innovation 181 Netra B. Chhetri Preface We are all familiar with the fascinating and ever changing weather. But as we grow older the memories we keep about weather is an accumulation of events. What we remember of weather after a long period of time, say few decades, is simply climate. Climate is in fact the statistics of weather, and as put by Ed Lorenz, climate, in mathematical terms, is the collection of all long-term statistical properties of the atmospheric state. Climate varies on a wide range of scales both temporal and spatial, and we often talk about local, regional or global climate, but also decadal climate variability and long term trends. Climate is a complex high-dimensional system involving highly non- linear interactions between many processes. Climate variation is controlled by external factors such as the solar activity, eg the 11-year cycle, and cyclic variations in Earth's orbital parameters and also internal factors such as anthropogenic changes in greenhouse gases. Weather and climate variability (and change) has great impact on our society as well as the environment. There is a large wealth of scientific literature on climate variability and change and its impact on the infrastructure and society. This book explores various perspectives about climate variability and change but is not meant to cover all aspects of the problem. The chapters in this book are divided into five sections. Section 1 consists of two chapters related to low frequency atmospheric variability. the first chapter provides a general but short review of the aspect of climate variabilitiy in two different climate regions: the North Atlantic/European sector in the extratropics and the Indian monsoon region in the tropics. Despite their climatic differences the two regions share common features related to nonlinearity where the atmospheric variability on intraseasonal time scales is characterised by an on-off switching between different weather regimes. Chapter 2 explores the land-atmosphere coupling strength using an ensemble of general circulation models from the Global Land-Atmosphere Coupling Experiment. Low- frequency atmospheric variability plays an important role in land-atmosphere coupling and precipitation predictability. Section 2 consists of one chapter and explores the connection between solar activity and space weather and Earth's climate. Chapter 3 discusses both the supportive and controversial arguments of the solar effect on Earth's climate, and presents a different perspective to climate change. X Preface Section 3 consists of two chapters related to one of the most important modes of climate variability: the El-Nino Southern Oscillation (ENSO). Chapter 4 discusses the benefits and prospects of ocean observation data asimilation for ENSO monitoring and seasonal forecasting. The quasi-coupled data assimilation system shows significant skill improvement of seasonal ENSO and atmospheric forecasting. Chapter 5 analyses the effect of one typical ENSO-type wind stress on the volume and heat transport variability in the world ocean. This type of wind stress can affect not only the mixed layer and the thermocline but also the thermohaline circulation. Section 4 consists of two chapters and is devoted to rainfall, an important component of climate variability. Chapter 6 explores ways of assessing drought with particular application to Europe. The detrending method as well as the choice of the reference calibration period affect the sensitivity of drought assessment. Chapter 7 discusses a particular example of seasonal prediction of summer rainfall in the Bermejo river basin in Argentina. The southern annular mode phase and the Atlantic High have the most effect on summer rainfall in that region. Section 5, with two chapters, is devoted to the adaptation to climate variability and change. Chapter 8 provides a review of adaptation strategies to face the risk of future climate change with a particular focus on the African continent. It summarizes the context of adaptation in a varying climate as opposed to a changing climate, and provides recommendations on the implementation strategy. Chapter 9 presents a succinct review of the process of technological change of innovation and its relation to a varying climate. It provides a new perspective to climate adaptation by taking into account environmental technology. Abdel Hannachi Department of Meteorology, Stockholm University, Sweden [...]... less is known about how the land-atmosphere coupling is related to the 18 Climate Variability – Some Aspects, Challenges and Prospects different timescales of climate variability The intraseasonal variability of precipitation has a strong influence on the soil moisture variability (Wei et al 2008), but little has been done on the connection between this variability and land-atmosphere coupling In this... deeper than normal 4 Climate Variability – Some Aspects, Challenges Will-be-set-by-IN-TECH and Prospects 2 Icelandic low yielding warmer and wetter, than normal, conditions over Europe associated with colder and drier, than normal, conditions in northern Canada and Greenland The negative phase (Fig 1a) is the opposite of the positive phase and yields moist air into the Mediterranean and cold air in northern... WY+ (dashed) and WY− (solid) Reproduced from TH10 14 12 Climate Variability – Some Aspects, Challenges Will-be-set-by-IN-TECH and Prospects 5 Summary and conclusion We have reviewed in this chapter some specific characteristics relating to the nature of the large scale and low-frequency atmospheric variability The discussion focussed essentially on the nonlinear nature governing this variability Two... similar patterns but smaller amplitude 24 Climate Variability – Some Aspects, Challenges and Prospects 5 Respective role of land and atmosphere in soil moisture-precipitation coupling The above has shown that the low-frequency precipitation variability has an indirect but important connection to the computed land-atmosphere coupling More low-frequency precipitation variability in the model can lead to higher... underestimate the high-frequency (fast synoptic) variance and overestimate the low-frequency (intraseasonal) variance, especially over tropics and subtropics Multi-year simulations of these models, 20 Climate Variability – Some Aspects, Challenges and Prospects Fig 1 The GLACE parameter Ω for precipitation from ensembles (left column) W and (middle column) S, and (right column) their difference The six rows... reanalysis in the other Section 2 describes the data and methodology Section 3 discusses the case of the North Atlantic/European region and section 4 discusses the Asian summer monsoon case A summary and a discussion are presented in the last section 6 4 Climate Variability – Some Aspects, Challenges Will-be-set-by-IN-TECH and Prospects 2 Data and methodology 2.1 Data We have used the 500-hPa geopotential... closest 300 days to these peaks The left hand side peak corresponds to the southern jet regime characterised by its high pressure or blocking over 1 shown by the dotted lines in Fig 3 and are discussed later 8 6 Climate Variability – Some Aspects, Challenges Will-be-set-by-IN-TECH and Prospects Fig 3 Daily zonal-mean zonal-wind averaged over longitudes 0 − 60o W and pressure levels 925-700 hPa versus... daily 850-mb wind and OLR 12 10 Climate Variability – Some Aspects, Challenges Will-be-set-by-IN-TECH and Prospects Fig 8 (a) Leading empirical orthogonal function of JJAS ERA-40 OLR anomalies for the period 1958-2001 (b) Probability density function (upper solid curve) of the OLR index and the associated two Gaussian components of the mixture model (lower solid curves, indicated by R1 and R2) The dashed-dotted... WO10a, and which reflect the NAO variability Climate is by definition a high dimensional and complex system involving highly nonlinear interacting processes Nonlinearity means, in particular, that changes in climate due to changes in external forcing, such as greenhouse gases, do not scale linearly with the latter and surprises are expected to occur Weather and climate variability is not pure randomness... persistent GB blocking The central position seems to be related to the undisturbed state 10 Climate Variability – Some Aspects, Challenges Will-be-set-by-IN-TECH and Prospects 8 Fig 5 500mb geopotential height maps corresponding to the three PDF peaks of the jet latitude Contour interval 20 m, negative contours dahed and zero contour omitted Reproduced from WO10b of the jet given its proximity to the mode . CLIMATE VARIABILITY – SOME ASPECTS, CHALLENGES AND PROSPECTS Edited by Abdel Hannachi Climate Variability – Some Aspects, Challenges and Prospects Edited. Monahan an Fyfe 2006) , and for the North Atlantic these are the NAO and the EA 4 Climate Variability – Some Aspects, Challenges and Prospects Atmospheric Low Frequency Variability: the Examples. longer the leading empirical 6 Climate Variability – Some Aspects, Challenges and Prospects Atmospheric Low Frequency Variability: the Examples of the North Atlantic and the Indian Monsoon 5 Fig.