Context:
A recent study shows the effects of climate change on tropical cyclones could have far-reaching and multifaceted consequences around the world, not just in the tropics.
A New Study on Cyclone Risk
Researchers at ETH Zurich, Switzerland, examined how cyclones might behave in the future under a future climate scenario called SSP5-8.5.
The study found that:
- Cyclones will increase in intensity.
- They may occur in regions previously unaffected by such storms.
Understanding the SSP Framework
- Shared Socioeconomic Pathways (SSPs) are a set of five global scenarios that describe alternative paths for global socioeconomic development.
- They are used to understand how changes in society, economy, and technology might affect climate adaptation and mitigation efforts.
- SSPs are used in conjunction with climate models to project future greenhouse gas emissions and climate change impacts.
SSP5-8.5: A High-Risk Scenario
Combines the SSP5 world with a radiative forcing of 8.5 W/m².
- Radiative forcing is the amount of extra energy being added to the planet’s surface.
- Currently, radiative forcing is 2.7 W/m² above pre-industrial levels (1750).
- For comparison, keeping global warming under 2ºC by 2100 requires a radiative forcing of just 2.6 W/m².
According to scientist Chahan Kropf, is already gaining momentum.
| Highlights of the FindingsSection | Details |
| Study 1: Cyclones and Ecosystem Risk | |
| Methodology | · CLIMADA, an open-source risk modelling platform, was used. · Timeframes: 1980–2017 (historical), 2015–2050 (projected under SSP5-8.5) · Datasets: STORM-B, STORM-C (synthetic cyclone tracks), Holland model (simulated wind fields) |
| Terrestrial Ecoregion Classification | · Resilient: Frequently exposed, recovers quickly· Dependent: Regularly disturbed, cyclone-shaped dynamics· Vulnerable: Rarely disturbed, recovers slowly if exposed |
| Key Findings | · · Of world’s 844 ecoregions, 290 are already affected by tropical cyclones. 200 more are vulnerable and 26 resilient.· Even in resilient ecoregions, recovery time from storms could drop from 19 years (1980-2017) to 12 years (2015-2020) for high-intensity storms.· Most of these shifts may be in East Asia, Central America, and the Caribbean which have abundance of resilient or dependent regions. |
| Study 2: Impact on Mangroves | |
| Methodology | · Used a probabilistic spatially explicit risk index (measures the odds of an event and its expected spatial distribution)· Scenarios analysed: SSP2-4.5, SSP3-7.0, SSP5-8.5· Evaluated components:o Hazard (cyclone wind speeds and frequencies)o Vulnerability (mangrove’s adaptability to sea-level rise)o Exposure (mangroves’ overlap with high-hazard zones) |
| Risk Indicators | · Mangroves at risk if cyclone frequency doubles or newly exposed to storms· Ecosystem services at risk: carbon sequestration, coastal protection, fish stock |
| Ecological Impacts | · Increasing Risk for Mangroves Ecosystems: Up to 56% of mangrove areas worldwide could be at high to severe risk by 2100 in the SSP5-8.5 scenario.o Southeast Asia is expected to be the most affected:ü 52–78% of mangroves at high risk.· Possible irreversible transformation of some ecosystems· Cyclone belts may shift away from the equator, exposing unadapted ecosystems in higher latitudes to new threats |
| Recommendations | · Include long-term recovery time in risk assessments· Risk-sensitive conservation planning · Incorporate shifting disturbance regimes in decision-making |
UPSC Mains Practice Question
Q. Discuss how the SSP5-8.5 scenario affects the distribution and intensity of tropical cyclones, and analyse its implications for ecosystem resilience and conservation strategies.