I’m guessing that Malcolm Turnbull gets a fair few letters on any given day. You wonder how he has the time to read them all.

How do you prioritise the ones worth your attention and the ones that you can toss in the round-shaped filing cabinet under your desk?

Perhaps there’s some formula involved in picking out the ones worthy of a public response – some sort of computer model that measures time and effort against the votes you might get, the donors and lobby groups you can afford to upset and the sort of reaction you can expect from the mainstream media.

Either that, or the letters all get dropped into a giant hessian sack ready for a morning lucky dip.

Honestly, I’ve no idea.

But a factor that appears not to be all that important are ones warning of an unfolding crisis that threatens people’s way of life, impacts countries across the globe, condemns future generations to several metres of sea level rise and generally makes the future not all that pleasant.

The number of letters coming into the prime minister’s office of late from climate change and marine scientists warning of these sorts of scenarios would be very hard to miss, especially when they’re signed by some of the best informed scientists from Australia and the rest of the world.

The latest one to drop into Turnbull’s office/social media feed/sack/bin carries the signatures of more than 150 of Australia’s leading scientists who work at universities and government agencies across the country.

The letter says “governments worldwide are presiding over a large-scale demise of the planetary ecosystems, which threatens to leave large parts of Earth uninhabitable” and asks for “meaningful reductions” in greenhouse gas emissions and cuts to coal exports.

The letter, coordinated by Australian National University Earth scientist Dr Andrew Glikson, lays out a few facts.

July 2016 was the hottest month the world has experienced on a temperature record going back 136 years. Levels of carbon dioxide in the atmosphere are rising at a rate not known in at least 55m years. Daytime heat records in Australia are being broken three times as often as cold records. Ice sheets are melting at an increasing rate and sea level rise was is accelerating.

Once he had collaborated with colleagues to refine the text, it only took Glikson a couple of days to gather the signatures.

He told me there was an increasing sense of frustration among scientists that warnings and predictions, stemming from peer-reviewed research over many years, were going unheeded in the corridors of power.

He put the lack of genuine action to cut greenhouse gas emissions down to two things: a media that downplays or ignores the issue, and a fossil fuel industry with too much power over the political process.

Many people just don’t understand the issue because there has been something of a cover-up across many parts of mainstream media, with a few exceptions. Sure, the media reports the issue, but they don’t explain it.

But the fossil fuel industry is the largest in the world by far. There’s an enormous vested interest and the political elites just follow that money.

So Glikson admitted he didn’t “anticipate a response” from the prime minister’s office.

Scientists ask for coal cuts

The letter, like several others over the last year or so, have called for Australia to move away from its support for the fossil fuel industry, in particular coal.

In October last year, just before the United Nations climate talks in Paris, scientists joined campaigners and advocates to sign an open letter to world leaders asking for a moratorium on new coalmines in Australia.

Australia was in the process of doubling its coal exports, the letter said, something that was “incompatible with the world’s objective of limiting global warming below dangerous levels”.

In February this year, about 3,000 scientists from more than 60 countries sent a letter to the prime minister pleading for reconsideration of the drastic cuts to climate research planned at the CSIRO.

The letter said that rather than cut climate change research, what was needed was more investment.

Without committing to the continued development of next generation climate monitoring and climate modelling, billions of public investment dollars for long-term infrastructure will be based on guesswork rather than on strategic and informed science-driven policy. The societal benefits of climate science far outweigh the likely high costs of reacting to future climate change instead of strategically planning for it.

In June more than 2,000 marine scientists and reef managers from across the world sent Turnbull a letter asking his government to “stop endorsing the export of coal” and to “stop or revoke the approval of new mines”.

Graham Readfearn (@readfearn) Letter to @TurnbullMalcolm from 2k+ coral scientists asks for end to backing of coal exports and no more coal mines pic.twitter.com/4Cx6p2obWj

Coral reefs supported 500 million people worldwide, the letter said, but reefs were “threatened with complete collapse”

A quarter of marine species were at risk, exposing “hundreds of millions of people to decreasing food security and increased poverty”.

Advice from a former Malcolm

So let’s say thanks to either the luck of the draw or advice from his policy team, Turnbull finds himself reading the latest open letter from scientists asking for leadership on cutting greenhouse gas emissions. What should he do?

Maybe he could take some words of advice from a former version of himself?

We know that the consequences of unchecked global warming would be catastrophic.