Last month, about 500 corals in the Great Barrier Reef have been observed to undergo coral bleaching, the worst case ever.

However, this is about to get worse if the water's temperature continues to increase.

Truth be told, no coral is immune to possible bleaching, a process wherein the corals turn white after they expel algae, which have become toxic due to high water temperature or pollution.

Marine researchers discovered that this phenomenon doesn't happen uniformly in the Great Barrier Reef, especially in the last 30 years. This may mean that some have developed a protective mechanism to reduce the impact.

To test this hypothesis, they worked with Acropora aspera species and exposed it to three scenarios that simulate repetitive bleaching, single but major heat bursts, and protective trajectory, or the cranking up of water temperatures.

The results now published in Science suggest that those that went through protective trajectory were less likely to experience bleaching even up to the genetic level, which implies that the pulses of warmth prior to the major temperature spike can prepare the coral better, giving them bigger chances of survival - a condition the researchers call a practice run.

"I like the runner analogy. For those that can do a practice run first and do a little bit of training, they can handle it," explained Tracy Ainsworth, lead author and ARC Centre of Excellence for Coral Reef Studies researcher.

Here's The Problem

The world is getting warmer, and it's not good news for the corals at all. Not only will it eliminate the coral practice runs, but will also expose them to repetitive bleaching, which may only become more severe.

To make the news worse, all it needs is an increase of 0.5 degrees Celsius of the present temperature, which the researchers expect to happen within the next four decades. When this happens, the Great Barrier Reef corals could start to disappear by 2050s.

This may cause a significant ecological imbalance as the Great Barrier Reef is home to a wide variety of marine creatures including 1,500 different types of fish, as well as unemployment or a weaker economy as tourism suffers.

Recommendation

Fortunately, there's some hope. C. Mark Eakin, coordinator of the coral reef watch program of the National Oceanic and Atmospheric Administration (NOAA), emphasizes going beyond the Paris climate change accord and "looking at holding temperatures to a 1.5 degree increase or less."

Photo: Paul Toogood | Flickr