Lessons from the tropics for a global geomorphology

• Published in: Singapore journal of tropical geography Vol. 27; no. 2; pp. 111 - 127
• Main Author: Thomas, Michael F.
• Format: Journal Article
• Language: English
• Published: Melbourne, Australia Blackwell Publishing Asia 01.07.2006
• Subjects: climate change; climatic geomorphology; landscape sensitivity; rock-mass weathering
• ISSN: 0129-7619; 1467-9493
• DOI: 10.1111/j.1467-9493.2006.00246.x

Historically, geomorphologists have applied uniformitarian principles based on a temperate normality to all water‐worn landscapes. Isolation of tropical landforms within formal morphogenetic regions, which arose during the early history of the subject, has persisted. However, in a global geomorphology, plate tectonic motion, Milankovich cycles of climate change and invasive weather systems all render fixed climatic boundaries meaningless and, on every timescale of enquiry, interaction of the tropics with extra‐tropical regions is fundamental. In tropical regions, the continuity of weathering processes through geologic time emphasizes their contemporary relevance and, with knowledge of Quaternary climate changes, increases understanding of the nature of landscape sensitivity and instability and fluvial sedimentation on millennial timescales. Examples are illustrated from northeast Queensland, Australia and northwest Kalimantan, Indonesia. Global concerns centred on hazards and resources need to be addressed through a reciprocal exchange of ideas involving greater focus on tropical areas.