Yes is possible to generate secondary data base on the records obtained from the existing field data. You can request for 10, 20 or 30 yrs climate data on crop production and yield in synoptic stations in ur country.
According to the information given by Dr. (Ibrahim Sufiyan), the following multidisciplinary research, which is the result of my efforts, using 10 years of parametric and non-parametric statistics data, can help you in evaluating the goal.
Article Reflection of traditional farming operations on the sustaina...
information from Mr. Sufiyan can be done by taking secondary data related to climate such as temperature, humidity, rainfall, wind speed and secondary data related to yield for at least 10 years
Hristov, Jordan, et al. "Analysis of climate change impacts on EU agriculture by 2050." Publications Office of the European Union, Luxembourg, Luxembourg (2020).
secondary data for climate variability within a particular geographic area can be obtained by considering the data records of the essential climatic parameters such as Rainfall(precipitation), Temperature, Relative humidity, Wind, Sunshine, and Atmospheric Pressure within that particular area and comparing it to the previous 10-25 years data records to see the variability. You can contact any nearby meteorological station within the study area to help you with the data for the various climatic parameters.