Spatial Patterns and Magnitudes of Agriculturally Pertinent Climate Indicators across Agroecosystems in Türkiye

Abstract

Abstract This research utilized NASA–Prediction of Worldwide Energy Resource (POWER) datasets to quantify and map long-term annual and growing-season mean maximum, minimum, and mean air temperatures (Tmax, Tmin, and Tavg); diurnal temperature range (DTR); growing degree-days (thermal unit) (GDD); seasonal total precipitation; mean daily precipitation; incoming shortwave radiation Rs; relative humidity (RH); wind speed u2; saturation and actual vapor pressures (es and ea); vapor pressure deficit (VPD); grass- and alfalfa-reference evapotranspiration (ETo and ETr); and aridity index (AI) over the nine agricultural zones of Türkiye (Turkey). In addition to the latitudinal influence, the influence of continentality and oceanity effects and physiographic features were evident in the spatial patterns of all climate indicators. Tmin was the most spatially variable indicator at both scales, which can have significant impact on nighttime respiration, potentially reducing agroecosystem productivity. At the annual scale, climate indicators that showed coefficient of variation (CV) greater than 0.20 were GDD, Tavg, VPD, AI, and ea. Growing-season mean indicators with CV > 0.20 were GDD, AI, VPD, total precipitation, mean daily precipitation, and ea. The Rs showed the least spatial variability at both scales. Annual-scale mean CV (0.21) was 7% greater than that the growing season (0.19). To the best of our knowledge, the analyses, information, and resources presented here are the first to quantify agricultural-zone-specific climate indicators during the growing season in Türkiye and are invaluable for decision-making on issues at the intersection of meteorology, agriculture, water resources, and hydrology.