These waters in eastern Tasmania are warming at a faster rate than the global average. Even though there is a subject of debate as to how much faster, the two sides of the debate agree on the 2.3-degree increase. The National Oceanic and Atmospheric Administration say this is twice the global average. The Institute for Marine and Antarctic Studies says this is equating to roughly four times the global standard.
They study different things, in different ways with different technology. But the disagreement doesn’t bland the agreement: it’s faster than anywhere else on Earth.
The main consequence of the worrying conclusion is the almost disappearance of the kelp forest. And along with it, oceanic species like abalone and rock lobster. 95% of the kelp is gone, fisheries got pushed to the brink, and the state’s oyster stocks got diseased. This puts the Tasmanian waters on the very high end in terms of the magnitude of losses that were seen over the last several decades.
Tasmania Climate Is Changing From Temperate to Tropical
Kelps are large brown algae. They need nutrient-rich water with temperatures between 6 and 14 degrees Celsius. They have a high growth rate. Some of them can grow as fast as half a meter a day, sometimes reaching 30 to 80 meters. The temperature growth has already endangered it. But there is something else that also made it disappear.
The warming made the waters suitable for long-spined sea urchin populations to explode on Tasmania’s east coast. The invasive species will presumably transform the Tasmanian peninsula from the temperate environment into a tropical one. They have devoured the kelp. Since 1978, when urchins were a curio, today they can be countered in millions.
Tasmania is now home to reef-building corals. In future years the east coast will be nothing but bare rock if the climate doesn’t decrease and urchin invasion won’t be contained. The waters off the south-west of Madagascar, the Galapagos Islands, the Arctic Circle, and the south-western tip of Australia are also endangered by climate change and prone to face the same faith as Tasmania.