Revision summary
Young fold mountains follow the Alpine–Himalayan and American cordilleran belts. Island arcs mark Pacific subduction. Alignment sets orographic rain, rain shadow, and foehn winds. Himalaya and Western Ghats are India’s teaching pair. Altitude zonation on Andes and Himalaya is climate stacked by height.
Model answer
Copper italics in this answer — like this — are the key facts. Each one is unpacked in the Facts & figures rail.
Introduction
The world’s great ranges are not random wrinkles. They follow plate edges and old orogenies, and they steer wind, rain, and temperature for the people at their feet.
Body
Alignments
- Young fold west–east: Alps, Carpathians, Caucasus, Zagros, Himalaya–Karakoram — the Alpine–Himalayan belt from the Atlantic to the South China Sea.
- Young fold north–south in the Americas: Rockies and Andes along the Pacific Ring of Fire.
- Island arcs: Japan, Philippines, Indonesia — volcanic mountains on subduction trenches.
- Old residual: Urals (N–S), Appalachians, Western Ghats (more scarp than Alpine fold), Aravallis — lower, worn, still climatic.
Weather impacts, with examples
- Orographic rain and rain shadow: Western Ghats make the Konkan wet and the Deccan lee drier; Himalaya wring the monsoon onto India and leave Tibet and interior Asia drier; Cascades rain-shadow the US interior.
- Barrier to cold air: Himalaya largely blocks Siberian outbreaks from north India in winter, while also trapping western-disturbation moisture as snow.
- Foehn / chinook: downslope warming on the leeward Alps and Rockies melts snow and dries farms.
- Altitude climate: Andes and Himalaya create vertical zonation — coffee, potato, pasture — on one slope.
- Monsoon channel: Arakan Yoma and Naga hills steer Bay moisture into Northeast India; the gap at the Brahmaputra is a wet funnel.
- Mediterranean west coasts: west–east Alps help isolate a milder south; north–south Pacific ranges shape California’s wet-west, dry-inland pattern.
Local life
- Tea on Darjeeling slopes, rainfed rice on windward Konkan, and snowmelt rivers of Punjab are weather written by alignment.
Flow diagram
flowchart TD AL[Alpine Himalayan E-W] --> OR[Orographic rain] AN[Andes Rockies N-S] --> RS[Rain shadow foehn] OR --> WX[Local weather] RS[RS] --> WX[WX]
Conclusion
- Major ranges align with plates: east–west in Eurasia, north–south in the Americas, arcs in the Pacific. They make rain, shadow, foehn, and altitudinal belts. Name the range, then name the wind it stands in.
Quick related
Students also ask
-
Discuss the geophysical characteristics of Circum- Pacific Zone.
Next question on this syllabus topic (2020 · Q4). View answer →
-
Do all mountains run east–west?
No. The Americas’ cordillera is mainly north–south. Alignment follows the plate boundary.
-
Is the Western Ghats a fold Himalaya?
No. It is largely a faulted-and-eroded edge of the Deccan, but it still wrings monsoon rain.
Same topic · past papers
UPSC has asked this before
These previous-year questions sit on the same topic. Open one to practise the earlier ask.
-
2019 · Q15 · GS I · 15 marks
How can the mountain ecosystem be restored from the negative impact of development initiatives and tourism?
More from this topic
Q17 · UPSC Mains 2026 · GS I · 15 marks · Solution
Analyze the major drivers of human-induced land-use changes in India and their geographical consequences.
World's Physical Geography
Anthropogenic pressures driven by population growth and economic development are the primary catalysts of rapid land-use and land-cover change (LULCC) across India. Agricultural expansion and intensive multi-cropping, particularly
Q16 · UPSC Mains 2026 · GS I · 15 marks · Solution
"The centre of global trade is gradually shifting from the Atlantic region to the Indo-Pacific region." Examine this statement.
World's Physical Geography
• The global center of economic gravity has decisively shifted from the Euro-Atlantic axis to the Indo-Pacific. • The rise of China, Southeast Asia, and India as primary manufacturing and consumption hubs drives this transition. • Vital maritime chokepoints like the Malacca Strait serve as critical arteries for global energy and merchant trade. • Mega free-trade agreements such as RCEP and IPEF have established new regional trade and rule-making architectures. • Post-pandemic supply chain vulnerabilities have accelerated diversification strategies like 'China-plus-one' and 'friend-shoring'. • Control over critical mineral supply chains powers the ongoing digital and green energy transitions in the region. • Sustaining this geo-economic shift requires robust multilateral frameworks, freedom of navigation, and rules-based maritime governance.
Q14 · UPSC Mains 2026 · GS I · 15 marks · Solution
Compare the Loo, Chinook and Foehn winds with respect to their regions of prevalence, their nature and climatic impacts.
World's Physical Geography
• Local winds like the Loo, Chinook, and Foehn are driven by distinct regional pressure gradients and orographic barriers. • The Loo prevails over the Indo-Gangetic Plain, the Chinook along the Rockies' eastern slopes, and the Foehn across the northern Alpine valleys. • The Loo is a scorching, dust-laden convective surface wind generated by intense summer continental heating. • Both the Chinook and Foehn are warm, dry katabatic winds formed via rapid adiabatic compression on the leeward sides of mountains. • The Loo induces severe agricultural stress, crop wilting, and high health risks like heat strokes in South Asia. • Chinooks act as 'snow eaters' in North America, rapidly melting winter snowpacks and opening up pasturelands for grazing. • Foehn winds accelerate Alpine snowmelt, which simultaneously triggers hazardous avalanches and elevates regional wildfire risks.