Aspects of Heat Availability and Heat Demand of Crops in the Context of Climate Change (Ararat Valley and Foothill Zone)

The specificities of heat availability and crop demands for the sum of temperatures above 10°C on the territory of the Ararat Valley and its foothills are discussed. The patterns of multiyear fluctuations of heat availability are assessed in the context of the global climate change, and forecasts are made. The daily actual observations of data from nine meteorological stations located in the area studied along with the agroclimatic reference books and yearbooks were used. Mathematical statistical, extrapolation, analytical, and correlation methods were applied. It has been demonstrated that heat supply conditions in the region are favorable for the growth and development of various crops, although the danger of late spring and early autumn frosts should be taken into account. It has been shown that heat availability is unevenly distributed across the territory studied, and it decreases naturally with increasing altitude, changing from 4486 to 3012°C and lower with the vertical gradient of 175°C/100 m. The interannual course shows an increasing trend in heat availability, which actually increased by 428°C, on average, from 1993 to 2022. This is favorable for cultivation and expansion of sown areas of many new thermophilic and drought-resistant varieties of high-yielding crops.