Search or add a thesis

Advanced Search (Beta)
Home > Spatiotemporal Impact of Temperature and Precipitation on the Cryosphere of Pakistan in Changing Climate

Spatiotemporal Impact of Temperature and Precipitation on the Cryosphere of Pakistan in Changing Climate

Thesis Info

Access Option

External Link

Author

Waqas, Ahmad

Program

PhD

Institute

COMSATS University Islamabad

City

Islamabad

Province

Islamabad.

Country

Pakistan

Thesis Completing Year

2019

Thesis Completion Status

Completed

Subject

Meterology

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/11157/1/PhD_Thesis_Waqas.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727217397

Asian Research Index Whatsapp Chanel
Asian Research Index Whatsapp Chanel

Join our Whatsapp Channel to get regular updates.

Similar


This research thesis is mainly focused to assess changes in the daily observed temperatures and precipitation over the Hindukush, Karakoram and Himalaya mountains of the northern Pakistan (HKNP) which is a permanent source of fresh water (in the form of large glacial bodies with perennial snow cover) for Pakistan’s largest Indus River system that fulfills a large fraction of the water demand for agricultural land of the country as well as hydropower generation and other domestic purposes. The current research work has three aspects: Firstly, spatiotemporal variability in the observed daily maximum temperature (Tmax), minimum temperature (Tmin) and mean temperature (Tmean) for a recent 30year period (1986–2015) is examined from a total of 18 different weather stations in the HKNP region by employing probability distribution functions (PDFs) on annual and seasonal basis. The observed river discharge is used to assess the impact of temperature variations on the glaciers and snow covers of the HKNP region. The temperature based PDFs show a significant mean decadal warming of 0.45 °C, 0.03 °C, and 0.25 °C, in Tmax, Tmin and Tmean of the region, on annual basis, respectively. However, the observed river discharges based PDFs of the region show a mean negative decadal shift of −40.15 m3/s on annual basis. The negative decadal shift in river discharge in warm climate is discussed in terms of percentile based analysis which quantifies temperature changes for each percentile. The results revealed that the decadal changes in Tmin percentiles are more correlated with river discharge than decadal changes in Tmax and Tmean percentiles, on annual basis. The seasonal analysis showed a significant positive decadal shift of 1.93 °C for Tmax in spring season, whereas winter season showed a significant negative decadal shift of −0.56 °C in Tmin of the HKNP region, from first decade (1986–1995) to third decade (2006–2015), respectively. The rest of seasons (i.e., summer and autumn) displayed high variability in the Tmax, Tmin and Tmean in the HKNP region. A high observed (non-parametric) correlation between the observed total cloud cover (TCC) and temperatures of the region indicates that changes in regional cloud cover might have influenced the regional temperatures. Secondly, spatiotemporal variability in the observed daily diurnal temperature range (DTR) is assessed for same weather stations for 30-year period (1986–2015) both on seasonal and annual basis. The DTR is a difference of Tmax and Tmin. The regional mean DTR is 13.27 °C on annual basis, with a maximum in autumn (14.63 °C) and minimum in winter (11.81 °C). On annual basis, the regional DTR has increased significantly at a rate of 0.34 °C per decade, during the 30-year study period at p ≤ 0.05, based on Mann-Kendall test. On seasonal basis, the DTR displays an increasing trend in all four seasons with largest significant increase in the winter season at a rate of 0.32 °C per decade. The DTR is positively correlated with Tmax of the region on seasonal and annual basis. A strong negative correlation is found between the DTR and observed TCC in all seasons, indicating that variability in TCC has a considerable impact on the variation of DTR in this region. The statistically significant increasing DTR trend along with statistically significant decreasing trend of TCC in spring season suggests an early melt of snow and ice cover in the region, consequently changing the hydrological cycle of the region that demands a better water resource management in the HKNP region. Thirdly, spatiotemporal variability in the observed daily precipitation is assessed by employing the precipitation based PDFs that show a significant positive mean decadal shift of 0.13 mm/day from 1996–2005 to 2006–2015 in the HKNP region, on annual basis. The seasonal analysis shows a positive mean decadal shift of 0.18, 0.18, and 0.16 mm/day for precipitation of the region, in winter, summer and autumn season, from 1996–2005 to 2006–2015, respectively. It is further observed that the intensity of extreme precipitation events also increases progressively (from 213.8 to 257.0 mm/day) during 1986–1995 to 2006–2015 for summer season in the HKNP region. Along with temporal shifts, spatial positive (negative) precipitation shifts are also noticed in the western (eastern) parts of the HKNP region. The percentile based analysis shows that wet days (< 2.5 mm/event) are directly correlated with seasonal snow cover distribution that shows increasing trend for summer season in changing climate in the north eastern part of the HKNP region. A progressively increasing high observed non-parametric correlation from 0.54 to 0.71 between the observed precipitation and river discharge of the region is observed in recent decade (2006–2015) which requires a more strategic water resource management in the HKNP region in the coming years in line with earlier findings in this thesis research. Cumulatively, the thesis work is an effort to highlight the outcomes generated by employing frequency distribution based methods on the recent daily observed temperatures and precipitation in the HKNP region. These methods were ignored in previous research studies conducted specifically in the HKNP region. The outcomes of these methods not only provide a more detailed assessment of climate change impacts on the cryosphere of the HKNP region, but also provide a reference document for many related applied research aspects in the coming days.
Loading...
Loading...

Similar Books

Loading...

Similar Chapters

Loading...

Similar News

Loading...

Similar Articles

Loading...

Similar Article Headings

Loading...

قاضی محمد جلیل عباسی

قاضی محمد جلیل عباسی
افسوس ہے گزشتہ مہینے میں دو دنوں کے وقفے سے ملک و ملت اور علم و دین کے دو خادم ہم سے جدا ہوئے، جناب قاضی محمد جلیل عباسی نے طویل علالت کے بعد ۷؍ نومبر کو لکھنؤ میں داعی اجل کو لبیک کہا۔ وہ مشہور قومی و ملی کارکن، اردو تحریک کے ممتاز رہنما اور دینی تعلیمی کونسل کے بانی قاضی محمد عدیل عباسی مرحوم کے چھوٹے بھائی تھے۔ دونوں بھائیوں نے اپنے وطن بستی (سدھارت نگر) کی ترقی و خوش حالی کے لئے گوناگوں مفید کام کئے، قاضی جلیل عباسی بھی اپنے بڑے بھائی کی طرح فرقہ ورانہ سیاست سے دور اور کانگریس سے وابستہ رہے، ان کی زندگی قومی خدمت کے لئے وقف تھی۔ ایک زمانے میں ریاستی وزیر اور پھر پارلیمنٹ کے رکن منتخب ہوئے۔ شرافت، ہم دردی، بے لوث خدمت کے ساتھ ان کا تعلق دین و مذہب سے بھی ہمیشہ رہا، اﷲ تعالیٰ قوم و ملت کے اس خادم کی مغفرت فرمائے، آمین۔ (ضیاء الدین اصلاحی، دسمبر ۱۹۹۶ء)

 

تعلیمات اسلام قیام امن کی اساس سیرت طیبہ کی روشنی میں

This article highlights the Islamic and the prophetic teachings regarding the promotion of peace. The human progress is directly associated with peace. The so-called peacemakers of the world have failed in their insincere and incompetent quest for peacekeeping, rather, they they have contributed to deteriorate peace furhter. Islām and its prophet (ﷺ) present the impeccable and practical methods and methodology to establish and maintain peace in society. We find that in all his roles and status, the prophet (ﷺ) of Islām is a symbol and model of peace. The very words of Islām and Muslim are the titles, enogh to indicate the approach of Islām towards peace. The author of this paper draws the attention of the readers that in its beliefs, ethical teachigs, laws, and rituals of worship, the sole aim of the Islām is to enhance and promote peace at the individual, as well as, the collective level. The scope of peace in Islām is not confined to the Muslims only, it includes the nonMuslim, too. Further, it encompasses animals and vegetation in its fold of peace. This is what the world needs to focus on and admit; and the media needs to highlight and promote, so that, the real image of Islām may come to fore and the false propaganda against it die away.

Recent Trends in Time Series Modeling and Prediction of Wind Data: Statistical and Fuzzy Reasoning Approach

We developed stochastic time series models such as ARMA( p,q), non- seasonal ARIMA, seasonal ARIMA (SARIMA) and MTM models to simulate and forecast hourly averaged wind speed sequences on twenty year data ,.i.e, 1985-2004 of Quetta, Pakistan. Stochastic Time Series Models take into account several basic features of wind speed including autocorrelation, non-Gaussian distribution and non-stationarity. The positive correlation between consecutive wind speed observations is taken into account by fitting ARMA process to wind speed data. The data are normalized to make their distributions approximately Gaussian and standardized to remove scattering of transformed data (stationary,.i.e., without chaos).Diurnal variations has been taken into account to observe forecasts and its dependence on lead times. We find the ARMA (p,q) model suitable for prediction interval and probability forecasts. But the MTM model is relatively better as a simulator compared to ARMA modeling. The suitability of ARMA (p,q) model for both long range (1-6 hours) and short range (1-2 hours) indicates that forecast values are the deciding components for an appropriate wind energy conversion systems, WECS. ARMA processes work with non-stationary (chaotic) data. Non-seasonal ARIMA models and the prediction equations for each month and indeed for each season of a twenty year wind data are presented. The seasonal ARIMA (SARIMA) and its prediction equations for each month of a twenty year data are also studied. With non- stationarity or chaos in data, stochastic simulator in the ARIMA processes does not effectively work although its prediction equations are good enough to forecast relatively short range reliable values. Various statistical techniques are used on twenty five years, .i.e., 1980-2004 data of average humidity, rainfall, maximum and minimum temperatures, respectively. The relationships to regression analysis time series (RATS) are developed for determining the overall trend of these climate parameters on the basis of which forecast models can be corrected and modified. We followed the coefficient of determination,.i.e., a measure of goodness of fit, to our polynomial regression analysis time series (PRATS). The correlation to multiple linear regression (MLR) and multiple linear regression analysis time series (MLRATS) are also developed from deciphering the interdependence of weather parameters. We used Spearman’s rank correlation and Goldfeld-Quandt tests to check the uniformity or non uniformity of variances in our fit to polynomial regression (PR). The Breusch-Pagan test was applied to MLR and MLRATS, respectively which yielded homoscedasticity (uniformity of variances in the distribution of data). We also employed Bartlett’s test for homogeneity of variances on a twenty five years data of rainfall and humidity, respectively which showed that the variances in rainfall data are not homogenous while in case of humidity, are homogenous. Our results on regression and regression analysis time series show the best fit to prediction modeling on climatic data of Quetta, Pakistan. We performed design free fuzzy logic (FL) time series prediction modeling on a twenty year wind data, .i.e., 1985-2004 for Quetta, Pakistan. We followed design free fuzzy logic and obtained prediction of hourly wind data for spring (February, March and April). Non-stationarity or random walk in wind data exists but it does not influence prediction. Mackey Glass (MG) simulation of wind data indicated chaos or non periodicity. Moreover, stable attractors are observed in MG-time series, the origin of which is yet unknown. The attractors seen in MG simulation do not influence FL time series prediction. We studied singleton and non-singleton type-1 back propagation (BP) designed sixteen rule fuzzy logic system (FLS) on hourly averaged wind data of twenty years ,.i.e., 1985-2004. We found that the BP designed 16 rule non-singleton-type-1 FLS is relatively a better forecaster than singleton-type-1.We find hidden or unraveled uncertainties such as non-stationarity and stable attractors. These uncertainties make the data chaotic. The criterion of selecting root mean square error (RMSE) for establishing comparison is not suitable for chaotic data. Non-stationarity in the data can be properly handled with non- singleton type-1 FLS, therefore, there appears no reason to use a type-2 FLS. The stable attractors and non-stationarity in our data do not affect the predicted values as confirmed by Mackey Glass simulation. The chaos can be effectively resolved through parallel structure fuzzy system (PSFS) which exploits time-delays.. A variety of Artificial Neural Network models for prediction of hourly wind speed (which a few hours in advance is required to ensure efficient utilization of wind energy systems) at Quetta, Pakistan is studied and the results are compared. Satisfactory results are obtained with Feed Forward Back Propagation Neural Networks (FFBPNN). An empirical relationship is developed which shows the Gaussian profile for the number of neurons which varies with lag inputs, .i.e., nn = k exp(-il2) where nn shows the number of neurons, il the lag inputs, and k the sloping ratio. Feed Forward Neural Networks (FFNNs) can be corrected with optimization of empirical relationship for simulators followed by back propagation technique. The disadvantages of FFNNs comprise of heavy computational requirements, and non-existence of Artificial Neural Network(ANN) design methodologies for deciding the value of the learning rate and momentum. Neural Network (NN) modeling is not suitable for chaotic data characterized by randomness and non-stationarity.