The statistical method is still one of the most important methods of long-range weather forecasting and climatic prediction. Although the statistical means and methods were unceasingly improved in recent years, the accuracy of statistical prediction have not marked progress. In this paper, the change of the correlative stability of climatic essential factors around several "abrupt climatic change" in recent 100 years were calculated and analysed. It is shown that the "abrupt climatic change" is one of the most important reason that it influenced the statistical correlation stability of climatic factors. So it is also one of the most important reason influencing the accuracy of statistical prediction.