Home / Environment / Shipping Fuel Change Worsened Coral Bleaching Event
Shipping Fuel Change Worsened Coral Bleaching Event
22 Jan
Summary
- Removing sulphur from shipping fuel intensified coral bleaching.
- Great Barrier Reef corals faced up to 10% more heat stress.
- Reduced sulphur emissions allowed 5-10% more solar energy on reef.
Regulations implemented in early 2022 to significantly reduce sulphur content in shipping fuels inadvertently amplified a major coral bleaching event on the Great Barrier Reef. The International Maritime Organization mandated a cut in fuel sulphur from 3.5% to 0.5%.
This reduction in sulphur pollution, while beneficial for human respiratory health and acid rain, also decreased the atmospheric shading effect. Research indicates that this allowed 5% to 10% more solar energy to reach the reef.
Consequently, corals experienced up to 10% greater heat stress during the 2022 bleaching, the sixth recorded mass bleaching event and notable for occurring during a typically cooler La Niña period.
Scientists emphasize that unlike long-lasting greenhouse gases, sulphur emissions dissipate within days. Therefore, simultaneous reductions in both air pollutants and greenhouse gases are crucial for effective climate action.
