مقایسهٔ روش‌ها

	مدل گردش عمومی	مدل اقلیم اقیانوس-اتمسفر کوپل شده	شاخص استاندارد بارش
حوزه	ژئوفیزیک	ژئوفیزیک	ژئوفیزیک
خانواده	Process / pipeline	Process / pipeline	Process / pipeline
سال پیدایش	1975	1975	1993
پدیدآور	Syukuro Manabe and Richard Wetherald	Syukuro Manabe, Kirk Bryan, and others	Thomas McKee, Neil Doesken, and John Kleist
نوع	Deterministic coupled atmosphere-ocean simulation	Coupled atmosphere-ocean climate system simulation	Probabilistic drought indicator
منبع بنیادین	Manabe, S., & Wetherald, R. T. (1975). The effects of doubling the CO2 concentration on the climate of a general circulation model. Journal of the Atmospheric Sciences, 32(1), 3-15.	Manabe, S., Bryan, K., & Spelman, M. J. (1975). A global ocean-atmosphere climate model with seasonal variation for future studies of climate sensitivity. Journal of Physical Oceanography, 5(1), 3-29.	McKee, T. B., Doesken, N. J., & Kleist, J. (1993). The relationship of drought frequency and duration to time scales. Proceedings of the Eighth Conference on Applied Climatology, 179-184.
نام‌های دیگر	GCM, Global Climate Model	AOGCM	SPI
مرتبط	3	3	3
خلاصه	A General Circulation Model (GCM), also called a Global Climate Model, is a three-dimensional numerical representation of the Earth's atmosphere, oceans, ice, and land surface that simulates physical processes governing weather and climate. Pioneered by Manabe and Wetherald in 1975, GCMs are the primary tools for understanding past climate, projecting future climate change, and investigating climate sensitivity to greenhouse gases and other forcings.	An Ocean-Atmosphere Coupled Model (AOGCM) is a comprehensive climate simulation that couples dynamic general circulation models of the atmosphere and ocean with explicit exchange of heat, momentum, and moisture at the interface. Developed by Manabe, Bryan, and colleagues in the 1970s, coupled models are essential for simulating climate change, ocean circulation changes, and climate-ocean interactions over decadal to centennial timescales.	The Standardized Precipitation Index (SPI) is a climate index that quantifies precipitation anomalies relative to historical norms, standardized to account for differences in precipitation climatology across regions. Introduced by McKee, Doesken, and Kleist in 1993, SPI has become a primary tool for drought detection and characterization, adopted by meteorological agencies worldwide for operational drought monitoring and early warning systems.