Al-Bīrūnī's Meteorology in its Context

This paper investigates the meteorological conceptions of the esteemed scholar al-Bīrūnī, with a focus on weather forecasting, particularly the solar-based ʿanwāʾ system, as opposed to the lunar-based system prevalent in the meteorological and astronomical tradition of the Arabs. Additionally, the study touches on al-Bīrūnī's understanding of the water cycle, precipitation origins, and climatology. An analysis of various works by al-Bīrūnī reveals his dedication to the subject, showcasing both his originality and a coherent framework of thought that connects his views to the wider fields of cosmology and physics. Given the absence of a dedicated meteorological text (the Kitāb al-ʿanwāʾ is lost), the study relies on passages found in other sources such as the Kitāb al-āṯār al-bāqiya, Kitāb al-Tafhīm, Kitāb al-Jamāhir, and so forth. From this analysis, several interconnected key principles emerge. The importance of geography and orography in understanding the meteorology and climatology of various regions is emphasized, highlighting the central role of mountains in these processes. First, al-Bīrūnī's conception of the water cycle closely resembles the modern understanding, as he describes an exogenous cycle that contrasts with the continuous generation of water in the Aristotelian tradition. He also demonstrates an understanding of vapor as dispersed water in the air, recognizing water as a finite natural resource bound to perennial renovation. By examining al-Bīrūnī's work, this paper presents a broad understanding of his meteorological thought, situating it within the broader context of his cosmological and physical ideas. Despite the absence of a dedicated meteorological text, the ample evidence found in his other works enables a thorough analysis of al-Bīrūnī's innovative contributions to the field. In conclusion, this study offers valuable insights into al-Bīrūnī's meteorological conceptions and their relationship to his broader intellectual framework. By doing so, it highlights the importance of geography, orography, and an exogenous water cycle, emphasizing al-Bīrūnī's originality and coherence in his approach to understanding the natural world. Further avenues of research are suggested in the conclusion.