Quantifying Phonological Shifts and Their Impacts on Human Health in Iran

Climate change is reshaping seasonal patterns worldwide, influencing both ecosystems and human health. This study quantifies phenological shifts across Iran by analyzing ۳۰ years (۱۹۹۳–۲۰۲۲) of daily minimum temperature data from ۷۶ meteorological stations and examines how extended growing seasons, due to earlier springs and delayed falls, prolong pollen in Iran. Using frost dates as indicators, the growing season length was calculated and trends were assessed. Results reveal a significant nationwide trend toward longer frost-free periods, with an average increase of ۷.۶۹ days. Approximately ۶۵% of the stations showed an extended growing season, most notably in the western and northern regions, while some southern areas experienced slight reductions. Stations such as Sarpol-e Zahab and Shiraz illustrate the regional variability of these trends, with Sarpol-e Zahab showing a ۴۰-day increase and Shiraz a ۳۷-day decrease in growing season length. The observed lengthening of the growing season has direct implications for agriculture and public health, particularly through the extension of pollen release periods and longer exposure to seasonal allergens.

کلیدواژه ها:

Climate change ، Freezing ، Seasonal shifting ، Allergy