The relationship between rainfall and temperature on wheat and barley production using multiple regression analysis in Wasit Governorate for the years 2004-2014

Abstract

This research aims to analyze the impact of climatic variables (rainfall and temperature) on the production of wheat and barley crops in Wasit Province for the period (2004–2014). The study employs a quantitative analytical approach using a Multiple Linear Regression model via the SPSS software. The results demonstrated a very strong positive correlation, with the correlation coefficient ($R$) reaching (0.820) for wheat and (0.877) for barley. Furthermore, the research revealed a high explanatory power of climate, as climatic variables accounted for (67.3%) of the variance in wheat production and (77%) in barley production. The study concluded that annual rainfall is the "governing variable" and the most significant factor in the production process; an increase of (1 mm) in rainfall leads to a production increase of (2.213 thousand tons) for wheat and (0.542 thousand tons) for barley. Moreover, the Model Significance tests (ANOVA) and diagnostic charts (P-P Plot) confirmed the efficiency of the derived mathematical equations and their high validity for predicting future production levels based on climatic elements. Consequently, the research recommends the adoption of predictive techniques, the expansion of supplementary irrigation projects to mitigate the impact of rainfall fluctuations, and the development of agricultural varieties more resilient to extreme climatic changes to ensure food stability in the province.