Climatology and Changes in Temperature Seasonality in the Arabian Peninsula

Changes in temperature seasonality influence a wide range of societal and natural activities. The characteristics of the temperature/thermal seasons in the Arabian Peninsula and how the seasons have changed remain unclear. Using observational and reanalysis data (1985–2022), this research (1) introduces a new approach to define seasons based on a hybrid hierarchical k-means clustering method, (2) documents the characteristics of temperature/thermal seasons, and (3) examines changes in the timings (onset and end) and lengths of the temperature seasons in the Peninsula. The results indicate that summer is the longest season (165 days), with the onset ranging from mid- to late April in the southern and northern Arabian Peninsula, respectively. Winter begins in late November and lasts until late February, with a length averaging around 92 days. Spring and autumn are the shortest seasons, lasting for about 52 days. The seasons demonstrate latitudinal patterns in their timings that correspond well to the seasonal changes in solar inclination. A trend analysis shows that summer is extending and becoming warmer, particularly at night. Winter is becoming shorter, with higher temperatures during both the day and night. Spring is starting and ending earlier, with a higher increase in the daytime temperature. The results of this research will be valuable in various applications relevant to sustainable ecosystems and human well-being.