The agricultural sector is considered one of the most important sectors affected by climatic changes due to the sensitivity of agricultural crops to temperature changes, whether by rise or fall, as the productivity of some crops decreases with the increase in temperature, while the productivity of some crops increases with this rise. As well as the poor quality of production, which will have an impact on Egyptian agriculture as well as Egyptian food security. Where the research aims to study the impact of the most important climatic changes-whether positive or negative- represented in (maximum temperatures-minimum temperatures- relative humidity - rainfall rate) on the productivity of the most important field crops in the new and old lands in the governorates of Egypt for the most widely recognized crop aggregates.
As it was clear from the results of estimating the Stepwise regression model using the random model method that the final outcome of positive climate changes leads to an increase in the productivity of the wheat crop in the total land by 0.01 tons / feddan, which represents about 0.39% of the average productivity of wheat in the governorates of Egypt, which is about 2.569 tons / feddan, in When the final outcome of the climatic changes was positive, it led to an increase in the productivity of the maize crop in the total lands by 0.07 tons / feddan, which represents about 2.37% of the average productivity of wheat in the governorates of Egypt, which is about 2.953 tons / feddan. While the final outcome of climatic changes was negative, leading to a decrease in the productivity of the rice crop in the total lands by 0.11 tons / feddan, which represents about 3.16% of the average productivity of wheat in the governorates of Egypt, which amounts to about 3.477 tons / feddan. It became clear that the final outcome of positive climate changes leads to an increase in the productivity of the cotton crop in the total lands by 0.036 tons / feddan, which represents about 3.03% of the average cotton productivity in the governorates of Egypt, which is about 1.187 tons / feddan.