Statistical Characterization of Climatic Trends in Delhi NCR (1990–2022) Using Regression, Dispersion Measures, and Correlation Analysis

Delhi NCR-Region, India, is considered one of those cities which draws nation-wide attention because of its extreme climatic dynamics. Hence, a comprehensive study of this region is required for assessing its extreme climatic trends, environmental stress, and urban degradation. The core objective of this study is to understand the climatic dispersions, inter-relationship between climatic variables, seasonal study, and quantify linear trend detection in Delhi NCR during the period 1990-2022. The data was obtained from Kaggle, comprising data variables of Daily Maximum Temperature (TX), Daily Minimum Temperature (TN), Daily Mean Temperature (T), and Daily Precipitation (PRCP), recorded at the Safdarjung Meteorological Station operated by the IMD. Daily observations spanning 1990-2022 were aggregated into annual mean values to construct a 33-year dataset for statistical analysis; standard deviation (σ) was calculated for dispersion analysis; seasonal analysis was performed to compare variations in temperature and rainfall; Pearson’s correlation method was conducted for inter-parameter relationships among the data variables; and linear regression model was deployed for analysing temperature trends. Results revealed that annual precipitation exhibited the highest variance (CV = 34%), whereas temperature variables showed relatively low variability (CV = 2.23–2.85%). Pearson’s correlation analysis conveyed strong positive relationships among temperature variables (r = 0.76 - 0.94), whereas rainfall exhibited negligible correlation with temperature. Statistical tests indicated significant upward temperature trends (P < .05), although the regression models achieved modest explanatory power (R2 = ≤ 0.44). Despite the variability, the statistically significant P-values indicate that the upward trajectory of the temperature trends is reliable. The identified warming trends emphasize the importance of continuous climate monitoring and adaptive strategies to mitigate rising heat stress and environmental risks in the study region. Overall, the research highlights significant long-term climatic trend analysis with potential implications for climate resilience strategies and government policy optimizations.