A comparison of bioclimatic potential in two global regions during the late twentieth century and early twenty-first century.

Changes in the general circulation of the atmosphere have been taking place during the latter part of the twentieth century and the early part of the twenty-first century. In the Belgorod region of Southwest Russia, this has been manifested in the more frequent occurrence of stationary anticyclones, including those referred to as blocking anticyclones, especially during the summer season. Also, there has been a general increase in regional temperatures during the growing season over the period mentioned above, and combined with the more frequent occurrence of anticyclones has led to less humid conditions. In the Missouri region of the Central USA, variability in the circulation on differing time scales within the Eastern Pacific plays a strong role in the conditions that impact the growing season. As a result of changes in climate and climate variability, the benefit to agriculture during this period produces mixed results for both regions. This work will evaluate the growing season conditions using indexes that combine growing season temperature and precipitation such as the hydrothermal coefficient (HTC) and the bioclimatic potential (BCP). Also, the interannual variability of these indexes in both regions was examined. In the Belgorod region, the increase in temperature combined with little change in precipitation produced mixed results in interpreting these indexes. This was accompanied by more variable conditions as revealed by these indexes in the early twenty-first century. In the Missouri region, there was little trend in either index over the time period and the tendency was toward less climatic variability in the HTC and BCP.