Tropicalization
A recent study published in the Nature journal sheds light on the phenomenon of tropicalization, where marine ecosystems undergo transformation due to the migration of tropical organisms towards temperate regions in response to warming temperatures.
This topic of “Tropicalization” is important from the perspective of the UPSC IAS Examination, which falls under General Studies Portion.
Understanding Tropicalization
Definition
- Tropicalization refers to the process by which temperate ecosystems are transformed due to the movement of tropical organisms towards higher latitudes.
- This transformation occurs as a response to rising ocean temperatures.
Primary Cause: Ocean Warming
- The primary driver of tropicalization is the warming of ocean waters due to climate change.
Mechanism of Tropicalization
Changes in North America
- As ocean temperatures rise, extreme winter cold events in North America are decreasing.
- This leads to the poleward expansion of tropical organisms, sometimes displacing temperate organisms.
Observations
- Warm-water species are increasingly observed in higher latitudes, indicating the spread of tropical organisms to temperate regions.
- Examples of species undergoing this migration include corals, echinoderms, molluscs, and various types of fishes.
Notable Facts and Incidents
The Blob: Marine Heatwave Incident
- “The Blob” was a marine heatwave incident that occurred from 2014 to 2016 along the British Columbia coast and off the coast of North America in the Pacific Ocean.
- It was characterized by a large mass of warm water.
- Impact: This heatwave led to a 22% loss of groundfish biomass in the Gulf of Alaska, affecting species vital to local ecosystems and fisheries.
Demersal Fish (Groundfish)
- Also known as groundfish, demersal fish inhabit the demersal zone, which is the bottom of seas and lakes.
- They are bottom feeders and play a crucial role in marine food chains.
- Examples of demersal fish include Alaskan pollock and Atlantic cod, which are important fisheries.
