Royal Australian Air Force pilots, Flight Lieutenant Simon Marshall (left) and Flying Officer Jake Nicholas, prepare to land a C-17A in Suva, Fiji, as part of Operation Fiji Assist. Most of the media attention focused on big-ticket purchases – such as 12 new submarines costing $150 billion to build and operate – and China's displeasure at being the unnamed paramount threat. But the guidelines for Australia's future defence posture also make multiple references to the near-term risks global warming will pose to some of our fragile neighbours. "Climate change will see higher temperatures, increased sea-level rise and will increase the frequency and intensity of extreme weather events," the report says. "These effects will exacerbate the challenges of population growth and environmental degradation, and will contribute to food shortages and undermine economic development."

Members of Australia's reconnaisance and assessment team prepare to disembark a RAAF C-17A Globemaster aircraft at the Nausori International Airport in Fiji. In short, the military will be called on more often to respond to instability or natural disasters. Michael Thomas, a retired army major who has been advocating Australia join the US and other allies in paying greater heed to global warming, sees a shift in urgency compared with the Rudd government's 2009 version. Soldiers from 8th/9th RAR, and engineers from 2nd CER, clear the train line that runs through Grantham, Queensland, after flooding in 2011. Credit:Petty Officer Damian Pawlenko "Whereas the 2009 defence white paper stated the likely strategic consequences of climate change would not be felt until after 2030, this [paper] notes that climate change will be one of the key drivers that will shape the strategic environment 'to 2035'," Thomas says.

"This implies that climate change is not a far-off threat for tomorrow's generals. It is here to be dealt with today." Sailors on the flight deck of the HMAS Canberra during the Royal Australian Navy exercises off Jervis Bay last November. Credit:Kate Geraghty Climate change is not a far-off threat for tomorrow's generals. It is here to be dealt with today Michael Thomas, retired Australian Army major Bipartisan view The Gillard government's white paper in 2013 also identified the climate as a national security threat but this year's version is notable because it brings a bipartisan consensus for the first time.

"[I]t would probably not have happened under [former PM Tony] Abbott's leadership," Thomas says. "So credit [is] due to Malcolm Turnbull." That view of a political shift under Turnbull is also shared from afar. David Titley, a retired rear admiral of the US Navy who combines his scientific training as an oceanographer with his military rank to nudge the Pentagon to take climate change seriously, visited Australia's Defence Force Academy last October and detected the altered posture first-hand. "The thing that struck me was ... how much under the previous leadership, the defence bureaucracy had been intimidated into 'do not touch this issue'," Titley says. "You could see with the new PM, at least you could have that discussion." As with the Pentagon's Quadrennial Defense Review – "the 100,000-foot" overview of the US military's threats and capabilities – having climate change identified in the defence white paper as a challenge "is a very good step in the right direction", he says.

It gives policymakers or defence planners being grilled by politicians or their chiefs some cover, allowing them to point back to the paper when asked why Australia is spending more time or resources on the issue. Titley should know. He has testified before both sides of the polarised US political divide, including the mostly climate change-denying Republican leadership such as hard-right Texan presidential hopeful Senator Ted Cruz. Extreme extremes Titley sees parallels between the views of some Australian conservatives and those of the Texas Republicans, who typically dismiss the recent spate of record drought, heat and massive floods as merely a natural consequence of their highly variable climate. "Their view is" 'The rest of the country says it's extreme, we say it's Texas'," Mr Titley says. "At some point, though, everyone has a breaking point – but we're not sure where it is."

Australia's recent equivalents were probably the extreme heat prior and during Victoria's 2009 Black Saturday bushfires or the Queensland floods in 2011. Record national heat in 2013 was also backed up by a very hot 2014 and a record hot final three months to end 2015. Odd weather activity abounds even if the underlying climate signal may be hard to gauge. Australia this summer has had its second latest start to a tropical cyclone season in the past half century of reliable records, producing a relatively dry wet season across the north, while the south of the country faces a long and active fire season well into autumn. Sydney will post a February with just one day with a below average maximum temperature on current forecasts – the previous record low was five. The streak of 23 days above 26 degrees has eclipsed the previous record of 19 such days, and may run at least another week. Extreme weather events are among the climate challenges for Australia's military not just because of the extra demand anticipated for their services but also since many bases are exposed to impacts.

Creeping change But even the creeping background warming can't be ignored if it alters the ability of the military to train or operate. Extra heat affects troops' health while ill-planned live-fire exercises can have huge consequences – witness the State Mine fire during the searing spring of 2013 that started at an army range, destroying about 50,000 hectares and threatening Blue Mountains towns. Thomas says rising sea-levels are another encroaching risk the military has rightly identified, given naval facilities in particular typically hug the coast. What he finds hard to square with the military's increased concern about the matter is why another arm of the government – the CSIRO – is preparing to axe its world-renowned sea-level research team.

The threat to the Hobart-based group is part of sweeping cuts to CSIRO's climate programs that could halve or worse its research capacity to predict what's coming and advise the military – and the wider population – how to deal with it. "If these cuts proceed – who will do undertake this work?," he asks. "If anything, given that the defence white paper has now cited sea-level rise as a risk to our defence bases, there is a requirement for improved understanding and increased granularity of how sea-level rise will unfold across this century – not less."