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Title of Thesis

Muhammad Jawed Iqbal
Institute/University/Department Details
Institute of Space and Planetary Astrophysics/ University of Karachi
Atmospheric Physics
Number of Pages
Keywords (Extracted from title, table of contents and abstract of thesis)
hydrometeorological variability, global warming, rainfall pattern, monsoon, climate

The recent developments in atmospheric physics like that of global warming serve as complications playing up the standard climatological problem of rainfall/drought predictability for South Asia. This work attempts to understand a specific aspect of this issue viz. a systematic treatment of the problem of detection and modeling of hydro-meteorological variability over Pakistan. Chapter 1 defines the problem and demonstrates that to resolve it what seems to better suit is the stochastic approach to dynamical system study rather than the deterministic one.

After treating the missing data problem and resolving the data quality control question, Chapter 2 performs an exploratory analysis which shows that the annual landmass air temperature data models of five relatively more important climate stations of Pakistan constructed here obey the normal distribution while the constructed summer monsoon precipitation time series is lognormal. A subsequent trend analysis further establishes that the general pattern of evolution of temperature over Pakistan is pretty similar to the current global warming configuration. Our computations also indicate that the local precipitation pattern fairly agrees with the overall pattern of unprecedented rainfall / drought scenario obtaining today over the globe. It is reassuring to find that a bayesian analysis largely confirms the preceding results obtained classically for both temperature and precipitation.

To better understand the problem, Chapter 3 next takes up the question of physical character of processes governing the climate and shows that both temperature and precipitation of the major cities resemble a random fractal. A subsequent spectral analysis examines the question of temporal pulsations of the climatic processes. We show that the temperature of all major climate stations may be affected by ENSO or QBO or Sunspot Cycles. As for the rainfall, what we find is that Pakistan summer monsoon exhibits a fairly similar bienniality with that of the Indian monsoon.

To reinforce the discovery of mathematical processes at work behind the temporal evolution of phenomena, Chapter 4 applies pattern recognition techniques to analyse the spatial variability evinced by the seasonal data models for a large number of meteorological stations well spread over Pakistan. Unlike previous works. our classification leads to four climate zones for Pakistan, each with more detailed characterisations in terms of the geographical features and the climatical conditions of different localities.

In view of the critical influence of inter-annual variability in rainfall on agriculture, industrial production, etc., Chapter 5 considers the modeling and forecasting problem for the summer rainfall pattern for Pakistan. It is shown that the predictors arising from the Himalayan range and the Arabian Sea climate and more general global climatology lead to a simple new model for the physical process of local summer monsoon precipitations. Finally, Chapter 6 gives a summary of the results obtained in the preceding chapters and a discussion. This includes the possible lines of inquiry to improve and / or extend this contribution and its relevance.

Download Full Thesis
4754.36 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
184.43 KB
2 1 Introduction 1
844.2 KB
  1.1 Terrestrial Climate Variability And Its Hydro-Meteorological Dimensions With Special Reference To Tropics 2
  1.2 Climatic Setting Of Pakistan Region 7
  1.3 Dynamics Of Monsoon Flow Over Pakistan 10
  1.4 Rainfall Forecast Problem In The Context Of Pakistan 22
  1.5 Literature Review 26
  1.6 On The Need Of A Fresher Approach Of Modelling Of Fluctuation Of Local Climate Parameters For A Construction Of Rainfall Forecasts: Case Study Of Pakistan Region 27
3 2 Construction And Preliminary Analysis Of Data Model Of Climate Parameters 32
1002.54 KB
  2.1 Climate Data Sources 33
  2.2 An Imputation Scheme For Missing Data Problem 33
  2.3 Identifying Erroneous Measurements 34
  2.4 Examining The Long Time Series Of Climate Parameters For Homogeneity 36
  2.5 Exploratory Analysis Of Constructed Data Models 45
  2.6 Quantifying Evolutionary Trend Within Data Models 52
  2.7 Detecting Hidden Monotonicity In Climate Variability 55
  2.8 Applying Bayesian Inferencing Approach 61
4 3 Physical Structure Of Climate Evolution 67
923.84 KB
  3.1 Ascertaining Randomness Of Parameter Evolution Represented By Constructed Data Model 68
  3.2 Figuring Out Type Of Randomness Exhibited By Temperature Evolution 79
  3.3 Question Of Randomness Of Monsoon Precipition 87
  3.4 The ‚€˜Minus Two‚€™ Law Of Climatic Variability In Pakistan 87
  3.5 Pseuo-Stochasticity Of Long-Term Climate Fluctuations 90
  3.6 Spectral Analysis Of Local Climatic Fluctuations 97
5 4 Spatial Variability Of Climate 108
300.27 KB
  4.1 Climate Data Reduction 109
  4.2 Cluster Analysis Of Climate Parameters 109
  4.3 Climate Zonation Via Modern Pattern Recognition Techniques 113
  4.4 Fixing Meteorological Characteristics Of Zones Under The New Zonation 116
6 5 A New Rainfall Model For Pakistan 119
613.16 KB
  5.1 Pakistan Summer Monsoon Rainfall Index, I p 119
  5.2 Components Of Atmosphere-Ocean-Land System Shaping I p 124
  5.3 Construction A Model Of Summer Monsoon Rainfall 133
  5.4 Validating The New Model 140
7 6 Summary And Outlook 144
178.85 KB
  6.1 Summarising The Results 144
  6.2 Discussion And Conclusion 148
8 7 Appendix 150
935.79 KB
  7.1 References 169