As a marine ecologist who has been working on the Great Barrier Reef for 30 years I am today still stunned, often tearful, and ashamed to look my children in the eye. The Great Barrier Reef is undergoing change that means it will never be the same again in my lifetime. It will take decades to regrow.

To put this in a global perspective, considering the reef as a whole, an area of the reef the size of Scotland has coral in it that is largely dead.

If most or all the coral on a reef bleaches and subsequently dies, what is left can still be called a reef, however its ecological complexity and vibrant beauty is lost. Other animals including fish, some of which underpin our fisheries, are lost. Long-term recovery to its former glory can occur over a number of spawning seasons but, just like regrowing trees in a forest, it takes time and the right conditions.

Surely in anyone’s language this is an enormous environmental disaster?

The full scale of what is happening hit home for me having returned to the reef a year after working with Sir David Attenborough on the making of his three-part documentary series, Great Barrier Reef. Now many of the places that I had the privilege to show him near Lizard Island and on the outer barrier reef are fit only for a film crew wanting good examples of a dying or degraded reef.

In fact, international film-makers are flocking to the northern reef for exactly that reason. The rest of the world is seeing what our federal government seems unwilling to admit.

Is this doom-and-gloom scare-mongering? Does stating facts based on several independent levels of input and not on a few bits of non-expert hearsay endanger the reef-based tourism industry? Should we brush aside the science and procrastinate on difficult decisions yet again?

Politicians keep saying they are concerned but their actions, or lack of them, drown out their words. Any one of the analyses of how the latest budget failed the reef is enough to confirm this. Perhaps most astonishing in this shameful chapter in reef guardianship, the federal government tried to cover up what was happening by removing reef-related observations from a UN report.

I am now at a scientific conference in Germany, a country that takes renewable energy and climate change very seriously. My colleagues here from around the world are saddened by the continued loss of this world heritage site and astonished that “Australia is not doing enough”. I never thought I would feel ashamed to be an Australian. From here, our political leaders seem like a bunch of guilty schoolboys standing around a beautiful animal they have just pulled the wings and legs off. “I wasn’t there, it wasn’t me, I did not do it! Why doesn’t it work any more?”

The more responsible and caring response would be to confess our past failings and do better by our children so that their future has a reef in it. At the moment we are delivering them an environmentally bleak future.

Let’s think consequences again. Close to 70,000 jobs and $6bn in income are generated by the reef. These numbers far outweigh possible new jobs and potential financial input from the proposed new coalmine in Queensland, so I fail to understand the apparent gamble both state and federal governments seem willing to take.

When we consider the full capital value of the Great Barrier Reef, which runs to many billions of dollars – leaving aside its intrinsic beauty, biodiversity, wonder and World Heritage status – our current lack of action is crushingly irresponsible.

Why do we use terms such as value, jobs and even biodiversity to describe what the reef means to us? What is wrong with saying it is beautiful, stunning and a mind-blowing pleasure and privilege to see it?

I am struggling to get my head around the whys and wherefores of the complacency and lack of logical reasoning on this issue. I know there are many folks out there, both scientists and otherwise, who are also desperately worried for the reef – and reefs worldwide – and share this frustration. For more than 20 years marine scientists have issued cautions about the reef, and have associated these cautions with human-induced climate change.

There is no doubt about this connection. In Paris last year 190 countries finally agreed that human-made climate change is real and that we should act as a global community to combat the rise in temperature by reducing carbon emissions drastically and fast.

Notably in this respect, earth is about to pass 400 parts per million carbon dioxide in the atmosphere. Like the continued loss of the reef, the shrinking ice caps and loss of polar bears, penguins and other wildlife there, this 400ppm figure is an indication of our inability to act. The consequences of continuing this line of behaviour are more and more alarming, but continue we do.

In Australia, in the months after returning from the Paris climate talks, this failure was brought into sharp focus by the federal and state government of Queensland signing off on allowing one of the world’s largest coalmine to open right next the reef.

I have only one real question for Malcolm Turnbull, Greg Hunt and indeed for Queensland’s Labor party – what are we handing our children? The consequences of your actions now are removing one of the world’s most beautiful places from their future.

In his documentary Attenborough communicated this point far better than I:

Do we really care so little about the earth on which we live that we don’t want to protect one of its greatest wonders from the consequences of our behaviour?

I’m afraid at the moment that the answer to that somewhat rhetorical question appears to be that we don’t care at all.

But I refuse to leave my children facing the consequences of our inability to act. I refuse to wallow in despair or just accept that I am too little to make a difference. I think we can save the reef and that this will come through people power.

The key to reef survival is to ensure we look after it at both local (water quality) and global (climate change mitigation) levels. One cannot proceed effectively without the other. Please join me in this effort. At a local level, think hard about what you throw away and where you throw it. Think hard about what goes down the creek and if you are lucky enough to get to the reef, cherish every moment, show your children, share the wonder.

At a global level, do everything in your power to reduce your carbon footprint. Encourage whoever you can to run full pelt at renewable energy options. Leave the coal in the ground.