RESEARCH BASE
Search 3,721 documents across 34 fields — every claim tier-rated by evidence
3,633 are the core, quality-scored corpus (34 lettered sections — see How We Work); the remaining 88 are cross-corpus synthesis documents (68 InterDocs, 12 Connections, 8 Theories) also indexed here.
53 results for "tropical year" — page 2 of 3
C_5_26 — World Age Doctrine: Cycles of Creation and Destruction
The World Age Doctrine — the belief that cosmic time is divided into successive ages or epochs, each ending in destruction and giving way to the next — is one of the most widespread cosmological frameworks in human thoug
C_5_20 — Seasonal Ritual Cycles: Solstice, Equinox, and Agricultural Festivals
Seasonal ritual cycles — religious festivals, agricultural ceremonies, and sacred observances tied to the solstices, equinoxes, and the transitional points between them — represent humanity's oldest continuous relationsh
C_3_03 — Sacred Kingship and Divine Rulership
Almost every civilization in recorded history has believed that their rulers held power through a divine connection. This is not mere propaganda — it is one of the most universal patterns in human culture, emerging indep
C_3_05 — Aztec Cosmology and the Five Suns
Aztec (Mexica) cosmology describes the universe as having passed through four previous ages (Suns), each created and destroyed by different gods through catastrophic events — jaguars, wind, fire-rain, and flood. We live
C_2_08 — Venus / Morning Star Traditions
Venus, the brightest object in the sky after the Sun and Moon, plays a central role in myths across every major civilization. The Sumerians identified Inanna as the planet Venus, whose descent to and return from the unde
ZF_5_16 — Ocean Observation Networks: Global Monitoring of the Marine Environment
Ocean observation networks constitute the global infrastructure for monitoring the physical, chemical, and biological state of the world's oceans in near-real-time. The centerpiece of modern ocean observation is the Argo
ZF_1_14 — Ocean-Atmosphere Coupling: Heat Exchange, Evaporation, and Weather
The ocean-atmosphere interface — the boundary between Earth's two great fluid envelopes — is the planet's most important energy exchange surface. The ocean absorbs approximately 93% of the excess heat trapped by anthropo
K_4_03 — Limitation of Consciousness Motif
One of the most startling cross-cultural patterns in the world's mythological and philosophical traditions: ancient civilizations worldwide — separated by thousands of miles, thousands of years, and entirely independent
E_3_17 — Environmental Catastrophe–Civilization Correlation Timeline
Systematic cross-referencing of paleoclimate proxy records (ice cores, speleothems, tree rings, marine sediments) with archaeological and historical records reveals repeated correlations between abrupt environmental shif
E_2_08 — Little Ice Age — Climate, Society, and the Modern World
The Little Ice Age (LIA) was a prolonged period of climatic cooling that affected much of the Northern Hemisphere from approximately 1300 to 1850 CE, with coldest intervals during the Maunder Minimum (1645–1715) and the
E_2_11 — Snowball Earth Hypothesis
The Snowball Earth hypothesis proposes that Earth's surface was entirely or nearly entirely covered by ice on at least two occasions during the Neoproterozoic era (c. 720–635 million years ago): the Sturtian glaciation (
E_2_10 — Volcanic Winter and Civilizational Effects
Large volcanic eruptions can inject sulfate aerosols into the stratosphere, where they reflect incoming solar radiation, producing global cooling lasting 1–3 years — a phenomenon known as volcanic winter. The most severe
E_2_04 — Permian-Triassic Great Dying — The Biggest Mass Extinction
Approximately 252 million years ago, at the boundary between the Permian and Triassic periods, Earth experienced the worst mass extinction in its entire history — an event so devastating it has been called "The Great Dyi
E_2_01 — 536 CE Climate Catastrophe
This document examines 536 CE Climate Catastrophe, a topic within the Cataclysms and Chronology research area. Key areas of investigation include "The Worst Year to Be Alive", Historical Eyewitness Accounts, The Volcanic
E_4_13 — Milankovitch Cycles and Orbital Forcing
Milankovitch cycles are periodic variations in Earth's orbital geometry that modulate the distribution and intensity of solar radiation reaching Earth's surface, driving the glacial-interglacial cycles that have dominate
E_1_06 — Chicxulub Impact and the K-Pg Boundary
Approximately 66 million years ago, at the boundary between the Cretaceous and Paleogene periods (K-Pg boundary, formerly K-T boundary), a ~10 km diameter asteroid struck what is now the Yucatán Peninsula of Mexico, crea
J_2_22 — Terra Preta: Amazonian Dark Earth and Ancient Soil Engineering
Terra preta (Portuguese for "black earth") — scientifically termed Amazonian Dark Earth (ADE) — is a remarkably fertile, human-created soil found in patches throughout the Amazon Basin, primarily in Brazil but also in Co
ZB_5_22 — Deforestation, Land Use Change & Forest Ecology
Deforestation — the permanent conversion of forested land to non-forest uses — has transformed Earth's landscapes since the Neolithic agricultural revolution and accelerated dramatically since 1950. Between 2001 and 2020
ZB_4_01 — Biogeography and Island Biology
Biogeography — the study of the geographic distribution of organisms — was one of Darwin's and Wallace's most powerful lines of evidence for evolution and remains central to modern biology. Alfred Russel Wallace identifi
G_4_02 — Astrology as Historical Force and Political Tool
Astrology — the interpretation of celestial positions as meaningful for human affairs — is distinct from archaeoastronomy (→ [D_5_08](../../D_Sites_and_Artifacts/D5_Sacred_Geometry_Art_Symbolism/D_5_08_Archaeoastronomy_S
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