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A temporal analysis of landscape change patterns and consequent evaluation of urban expansion has been studied for the Dera Ghazi Khan city which is developing fast since 2000 as an emerging metropolis of South Punjab. The geospatial techniques particularly remote sensing augmented with GIS are vital tools and are mostly used in studying landscape changes and decision making for sustainable urban development. Four Landsat images (1991, 2001, 2011 and 2021) obtained from the free web of GLFC have been analysed. A supervised classification algorithm was applied to all images and results have been presented in both tabular and graphic forms. Present study, focuses upon two land-use classes i.e. built up and open areas, which will be monitored by land-use patterns of Dera Ghazi Khan city during 1991 to 2021 using satellite images. The graphical depiction of all the landscape changes, which have taken place in D. G. Khan city in the form of tables and maps provides detailed information about the degree and ratio of urban expansion and the changes in land use that occurred during the stipulated period.The classification was based on four categories i.e., urban land, bare soil, vegetation, and water; while maps were prepared to present the temporal changes in D. G. Khan city. A total of 52 sq./kms areas was selected for this study designated as the Dera Ghazi Khan city. According to the results, 33% of the urban area has been expanded in Dera Ghazi Khan from 1991 to 2021 and 19% vegetation cover has been reduced. It is a very alarming situation that agricultural land is decreasing because of urban expansion. The results revealed the significance of remote sensing and GIS in evaluating landscape changes.

There is a growing threat of urban flooding, particularly in Pakistan that needs attention and requireseffective management strategies. The chief trigger for urban flooding is the rapid and unplanned urbanization in areaswhere impermeable surface inhibits rainwater diffusion and changes the natural water flow. In many developedcountries, a technique of rainwater harvesting is implemented as a sustainable strategy to manage urban stormwater.Most studies and projects chiefly focused on the potential use of the Rainwater harvesting technique for waterconservation in arid and semi-arid climates. In the present work, GIS and remote sensing methodologies are utilized forthe suitability of rainwater harvesting structures. This study was conducted in Lahore, the second most populated cityof Pakistan and the capital of Punjab. Generally, the water harvesting technique depends on topographical areas withwater accumulation, where there is an availability of open spaces in the form of green areas and barren lands, rainfall,drainage network density, and rainfall distribution, particularly in the urban environment. The SRTM DEM data wereused for finding high water accumulated areas, and the Landsat OLI image is used to retrieve land use information i.e.vacant land and open green spaces, existing drainage network density, and rainfall distribution. All these layers wereintegrated through AHP to detect the potentially suitable sites for the construction of rainwater harvesting structures.Results concluded 94 suitable sites with categorization from highly to critically suitable for the construction ofrainwater harvesting structures in which 6 were highly suitable areas in Data Gunj Bakhsh Town and Ravi Town.Besides, residential areas are having a maximum site suitability percentage, followed by roads, agricultural and openspaces in the area under consideration. Considering the suitable sites, further rainwater harvesting methods can beidentified in the study area to alleviate urban flooding and improve the urban environment.

Identifying the temperature change at a regional level is one of the essential parameters to determine theintensity of climate change. The current investigation provides an examination of changing trends of temperature in thePunjab province from 1970 to 2019. Sen's slope estimator method is applied to monthly data of mean temperature(Tmean), maximum temperature (Tmax), and minimum temperature (Tmin) to calculate the rate of temperature change.Statistical methods were used to find out the level of significance in terms of negative or positive trends to examine thevariability among various weather observatories. Moreover, predicted values have also been observed for a detailedanalysis of temperature variability and trends. Significant and pronounced changes in the mean temperature (T mean) are distinguished all over the Punjab regions with an increasing trend from North to South Punjab. In the case of maximum temperature (Tmax), a faster rate of rising in temperature is observed over the Southern and Western regionsof Punjab. In contrast, the minimum temperature (Tmin) shows an increasing trend in Central Punjab. The findings provide detailed insight to policymakers for the planning of mitigating efforts and adaptation strategies in response to climate change.

This study investigates the tele-connection of the southeast Asian monsoon systems by comparing the summer monsoon (June to September) rainfall variability between Pakistan and south Korea. The daily data sets (1981-2014) of rainfall of Pakistan and south Korea are utilized to explore the possible link. Thedata products of the National Centers for Environmental Predictionand National Center for Atmospheric Research (NCEP/NCAR) were also used for the understanding of the large-scale atmospheric environments. The patterns of summer monsoon rainfall on a daily basis between Pakistan and south Korea followed to eachotherthroughout the year. Sub-seasonal differences of the summer monsoon revealed that July is the wettest month in both countries. The large-scale atmospheric environment of higher geopotential height revealed that the Tibetan high and the western north Pacific subtropical high are showing positive anomalies during positive phases over south Asia and east Asia,respectively. The anomalies of zonal wind are negative during positive phase and adversein the negative phase between 20-40oN. The reduced westerly is interpreted as the seasonal variation and moving of jet streams from the east Asian route. The Tibetan high, northwestern Pacific subtropical high and the east Asian jet stream have reliable and sufficient linkage between the Pakistan and south Korea summer monsoon system.

This study aims to investigate the perceptions of farmers residing in the drylands of south Punjab regarding the drivers of desertification mainly associated with meteorological and anthropogenic factors. Dataset of 399 respondents was collected using disproportionate stratified sampling technique from Bahawalpur, Rahim Yar Khan and Rajanpur districts. Pearson correlation and cross tabulation were performed to explore relation between variables. Simple Linear Regression (SLR) helped in investigating the association between natural and anthropogenic causes of desertification. The findings of this study indicate the significant variability in natural causes of desertification such as increasing temperature extremes, soil salinization and variationin rainfall patterns, while extensive land degradation, caused byanthropogenic factor, as leading to desertification in the study area. For Rajanpur, mean rainfall variation, supports the perception regarding major natural driver of desertification. Small-scale farmers were found to be most vulnerable to climatic extremes. SLR concluded that anthropogenic factorstriggeror intensify the natural drivers of desertification in the study area. Useful insights are provided regarding the perceptions of the local farming community regarding causes of desertification as appropriate perception of a risk leads to fruitful adaptation measures.

Present study examines the trends of extreme daily temperature and rainfall indices in some selectedmeteorological stations/districts of the Punjab. Due to paucity of data only six weather stations were selected from thewhole Punjab, having data of 33 years for temperature and precipitation on daily basis. A set of 14 indices(recommended by climate ET) were used to calculate the trends over a period of 32 years (1985–2017) by usingRClimDex (1.0) software package. These results showed that the number of tropical nights (TR20) and warm nights(TN90p) has been increasing in selected weather stations/districts and number for cool nights (TN10p) has been falling.Other temperature related indices trends such as, summer days, warms days, warm spell duration indicator (WSDI) andcool spell duration (CSDI) shows a mix pattern. The precipitation indices like SDII, RX1day, R10mm and PRCPTOTshowed an increasing trend in some selected stations. Most of the trends were not significant at level of 0.05 % whilemaximum day temperature increase has been observed at five out of six selected stations. Similarly, an average increasein precipitation in the vicinity of 3 mm per decade has been noted. The annual total rainfall and number of heavyrainfall days has also increased by 18 mm and 8.4 mm respectively during each decade. The analysis identified andhighlighted a slight change which was not temporally and spatially rational. However, there is need to more andadequate yearly data of different weather stations across the Punjab to identify the ongoing apparent and impeccablechanges in climate of the Punjab province.

The aim of present study is to evaluate and assess the impact of built-up areas on development of the urbanheat island (UHI).The study mainly focused on Lahore, which is one of the mega cities of Pakistan. In terms ofpopulation size, Lahore is the second largest city of Pakistan with 11.13 million inhabitants. The geospatial techniques(Remote Sensing and Geographical Information System) along with statistical applications were applied to find out theLand Cover Land Uses changes and consequent development of builtup areas over the period of 2000 and 2015. Tostudy the UHI, the meteorological data of each 30 minutes for 36 days starting from 30th June 2015 to 4th August 2015were collected through direct on site observation by using digital weather station. The results of UHI were crosschecked by obtaining land surface temperature by using thermal infrared (TIR) band 6 of the Landsat-7 TM. The resultsshow that the LCLU and built environment have direct impact on development of UHI. The areas where there wasmore vegetation cover had less temperature while in urban areas, the temperature was measured higher. Over the periodof 36 days, the average UHI remained 5.5°C and the highest intensity of UHI was observed as 8.3°C thus augmentedresearch rationale. The study suggests establishment of a thick network of automatic weather stations in Lahore togauge the urban heat island intensity and to plant indigenous trees on vacant swaths and develop urban forest tomitigate city’s rising temperature.

Lahore and Dhaka are rapid expanding and over populated cities of South Asia located in Pakistan andBangladesh respectively. The present study focuses on the evaluation of temperature variability in comparison of bothcities. This study primarily aims at the assessment and examination of temperature variations in both mega cities ofSouth Asia which are seasonal as well as the annual. The time series data were analysed by using statistical techniquesAutoregressive Moving Average Model (ARMA) and Autoregressive Integrated Average Model (ARIMA). The resultsreveal that the minimum temperature is increasing much faster than that of the maximum temperature of both cities.However, the temperature rise(in maximum and minimum) has been observed highest during the spring seasons in bothcities.

The purpose of present study is to investigate district and division wise annual rainfall variations over theprovince of Punjab, which is the largest in terms of population size as well important contributor in agricultural producein Pakistan. The results revealed that the rainfall trend has shifted from upper and lower Punjab towards the south,west, north and east respectively. The statistical analysis has inferred an overall increasing trend for the period 1990 to2000 and a decreasing trend during period 2001 to 2010 in Punjab province. The Z test value differences in the averagerainfall for each district level meteorological station have detected three increasing and two decreasing trends duringsummers of 1981-2015.The data revealed a significant changed seasonal trend observed in Murree and Sialkot(northern Punjab), Faisalabad and Lahore (central Punjab). Particularly, the changes have been observed in the southPunjab and over the central Punjab, while the same rainfall variations have shown a southward shift. The trend of therainfall had shifted in the Faisalabad division with the significant positive trend. In the Central Punjab, the positivetrend has also been found in all the districts. In the lower Punjab, Multan, Dera Ghazi Khan districts has shown anincreasing trend of rainfall. The findings are significant in changing agro-climatic zones in the Punjab and consequentshifting patterns of agriculture therefore can have net impact on the food security situation in the Punjab-Pakistan.

In a country like Pakistan, the presence of urban greening and parks are very essential for the well-being ofits citizens. The resident’s awareness about urban green spaces (UGSs) is essential as it would not only help towards ahealthier environment, but prepare residents to manage these spaces efficiently through local resources. This formulatesthe rationale behind current research work. This research is aimed at studying about the resident’s perception for UGS’sattributes like environmental, negative and positive. Another major focus of this research is to analyze thesocioeconomic differentials and its consequent impacts on resident’s perception about urban green spaces, which hasbeen probed with the help of MANOVA (Multivariate Analysis of Variance). In this regard the primary data of 223visitors were collected by random sampling method from eight major parks of Lahore, Pakistan. The findings of thissurvey of resident’s perception have shown that mostly male, single, low and middle class, and educated people visitthe urban green spaces and they are highly indebted by their environmental and health benefits. For the selectedcharacteristics of urban green areas, the resident’s perception has revealed that there exists an insignificant relationshipwith age and marital status of the respondents while the most significant relation was shown by the residents whovisited the UGSs regularly as ‘ρ’ value is less than the set significance level of 0.05. This study has highlighted a direneed of such UGSs in the city of Lahore which is known to be the “City of Gardens”. This could raise the spirits ofadministrators, city managers and planners to take immediate action in this regard.