At a Glance

"What we’re seeing is unprecedented,” says the biologist who captured the latest images."If this is the new normal, we're in trouble,” he said.

Warm water temperatures have caused new mass coral bleaching at Australia's Great Barrier Reef for the second year in a row, scientists reported Thursday.

The discovery was made during the first aerial survey of 2017, conducted by the Great Barrier Reef Marine Park Authority (GBRMPA), between Cairns and Townsville in northern Queensland.

Marine Park Authority director of reef recovery David Wachenfeld thatit is too soon to know how this year's bleaching event compares to that seen last year.

"The reef, of course, is bigger than Victoria and Tasmania combined, so it takes us quite a while to get the overall picture of everything that's going on out there," he said.

"To some extent, it's not as important whether this event is not quite as bad or worse than last year's," he said. "I think what's important is that the climate is changing and that is bringing a much greater frequency of extreme weather events to the Great Barrier Reef."

Images released by Greenpeace show the reef –the largest reef in the world that is home to an abundance of sea life –fighting for its lifeas yet another year of above-average water temperatures led to even more coral bleaching, biologist and underwater photographer Brett Monroe Garner .

“I’ve been photographing this area of the reef for several years now and what we’re seeing is unprecedented,” Garner said. “In these photos, nearly 100 percent of the corals are bleaching, and who knows how many will recover. Algae is already beginning to overgrow many of the corals.”

Garner noted that just a few months earlier, thecorals were full of color and life.

"Now, everywhere you look is white," he said. "The corals aren't getting the chance to bounce back from last year's bleaching event. If this is the new normal, we're in trouble.”

According to the National Oceanic and Atmospheric Administration (NOAA), (zooxanthellae) living in their tissues causing the coral to turn completely white.

Coral bleaching does not kill coral, NOAA notes, but it does place coral under more stress, which can eventually prove fatal.In 2016, and 22 percent of the entire reef died, according to the Australian Institute of Marine Science.

“Climate change is fueling warmer waters, cooking the reef alive. Once a coral is dead, it’s gone forever,” said Alix Foster Vander Elst, campaigner for Greenpeace Australia Pacific.

(PHOTOS:)

Neal Cantin of the Australian Institute of Marine Science (AIMS) said the recurrence of widespread coral bleaching in back-to-back summers indicates there has not been enough time between last year’s extreme heat event for the corals to fully recover.

“We are seeing a decrease in the stress tolerance of these corals,” Cantin said. “This is the first time the Great Barrier Reef has not had a few years between bleaching events to recover."

NOAA meteorologist and climate expert in an article for the organization's blog that "while some recovery will occur over time, the sad truth is that ongoing ocean warming may keep some reefs from ever recovering their previous level of health, diversity, and productivity."

Coral bleaching is not limited to the Great Barrier Reef.In 2005, thein one year due to a massive bleaching event caused warmer water temperatures, according to NOAA.

Garner called ongovernment officials worldwide to put an end to human-induced emissions to save the world's largest reef, and others like it.

“We have on our doorstep the clearest signal that climate change is happening, and that governments aren’t moving fast enough to stop it," he said. "We can still stop the reef’s destruction if we dramatically reduce global emissions.

MORE ON WEATHER.COM:XL Catlin Seaview Survey Coral Bleaching Great Barrier Reef June 2016

Before and after image showing coral after undergoing bleaching at Lizard Island on the Great Barrier Reef in March 2016, and the same reef in May 2016 after the coral had died.