Climate explained: how much does flying contribute to climate change?



Planes can create clouds of tiny ice crystals, called contrails, and some studies suggest they could have an a significant effect on climate.
from http://www.shutterstock.com, CC BY-ND

Shaun Hendy, University of Auckland


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

How much does our use of air travel contribute to the problem of climate change? And is it more damaging that it is being created higher in our atmosphere?

The flight shaming movement has raised our awareness of air travel’s contribution to climate change. With all the discussion, you might be surprised to learn that air travel globally only accounts for about 3% of the warming human activities are causing. Why all the fuss?

Before I explain, I should come clean. I am writing this on the train from Christchurch to Kaikoura, where I will give a talk about my recent book #NoFly: walking the talk on climate change. I have some skin in this game.




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Flight shame: flying less plays a small but positive part in tackling climate change


Staying grounded

Taking a train around New Zealand is no mean feat. In the North Island, the train between Auckland and Wellington runs only every second day. If you get off at a stop along the way, you have to wait another two days to continue your journey. You can catch a bus, but you’ll spend that bus journey fantasising about the possibility of an overnight train service.

So why do it? A good deal of global carbon emissions come from industrial processes or electricity generation under the control of governments and corporations, rather than individual citizens. For many of us, a decision not to fly might be the most significant reduction in emissions we can make as individuals.

As Swedish climate activist Greta Thunberg has shown, refusing to fly also sends a powerful signal to others, by showing that you are willing to change your own behaviour. Politicians and corporate sales departments will take note if we start acting together.

Impacts of aviation

Aviation affects the climate in a variety of ways.

Because any carbon dioxide you emit stays in the atmosphere for hundreds of years, it doesn’t matter much whether you release it from the exhaust pipe of your car at sea level or from a jet engine several kilometres high. Per passenger, a flight from Auckland to Wellington will put a similar amount of carbon dioxide into the air as driving solo in your car. Catching the train will cut your carbon emissions seven-fold.

When aircraft burn jet fuel, however, they also emit short-lived gases like nitrogen oxides, which can react with other gases in the air within a day of being released. When nitrogen oxides are released at altitude they can react with oxygen to put more ozone into the air, but can also remove methane.

Ozone and methane are both greenhouse gases, so this chain of chemical reactions can lead to both heating and cooling effects. Unfortunately the net result when these processes are added together is to drive more warming.

Depending on the atmospheric conditions, aircraft can also create contrails: clouds of tiny ice crystals. The science is not as clear cut on how contrails influence the climate, but some studies suggest they could have an effect as significant as the carbon dioxide released during a flight.

There is also considerable uncertainty as to whether aircraft exhaust might affect cloud formation itself – this could be a further significant contribution to warming.




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Growing demand for air travel

Offsetting, by planting trees or restoring natural wildlands, will take carbon dioxide back out of the atmosphere. But we would have to do this on a massive scale to feed our appetite for flight.

Emissions from international air travel are not included in the Paris Agreement, although the United Nations has been working on the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), which may begin to deal with these. Initially, the scheme will be voluntary. Airlines flying routes between countries that join the scheme will have to offset any emissions above 2020 levels from January 2021.

Emissions from flying stand to triple by 2050 if demand for air travel continues to grow. Even if air travel became carbon neutral through the use of biofuels or electric planes, the effects from contrails and interactions with clouds mean that flying may never be climate neutral.

With no easy fixes on the horizon, many people are thinking hard about their need to fly. This is why I took a year off air travel (alongside my colleague Quentin Atkinson) in 2018.




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I have been back on planes in 2019, but I have learned how to reduce my flying, by combining trips and making better use of video conferencing.

Fly if you must, offset if you can, but – if you are concerned about climate change – one of the best things you could choose to do is to fly less.The Conversation

Shaun Hendy, Professor of Physics, University of Auckland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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‘New Bradfield’: rerouting rivers to recapture a pioneering spirit


Waters from the Herbert River, which runs toward one of northern Australia’s richest agricultural districts, could be redirected under a Bradfield scheme.
Patrick White, Author provided

Patrick White, James Cook University and Russell McGregor, James Cook University

The “New Bradfield” scheme is more than an attempt to transcend environmental reality. It seeks to revive a pioneering spirit and a nation-building ethos supposedly stifled by the bureaucratic inertia of modern Australia.

This is not a new lament. Frustrated by bureaucracy, politicians in North Queensland have long criticised the slow pace of northern development.




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In 1950, northern local governments blamed urban lethargy. One prominent mayor complained:

… these young people lack the pioneering spirit of their forebears, preferring leisure and pleasure to hardships and hard work.

These sentiments were inspired by an agrarian nostalgia that extolled toil and toughness. Stoic responses to the challenges of life on the land are part of the Australian legend.

With drought devastating rural and urban communities and a state election looming in Queensland in 2020, both sides of politics have proposed a “New Bradfield” scheme.

An idea with 19th-century origins

Civil engineer John Bradfield devised the original scheme in 1938. His plan would swamp inland Australia by reversing the flow of North Queensland’s rivers. Similar proposals go back to at least 1887, when geographer E.A. Leonard recommended the Herbert, Tully, Johnstone and Barron rivers be turned around to irrigate Australia’s “dead heart”.

Blencoe Falls, on a tributary of the Herbert River, North Queensland, during the dry season.
Patrick White, Author provided

As the “dead heart” became the “Red Centre” in the 1930s, populist writers revived the dreams of big irrigation schemes.

These schemes have always been contested on both environmental and economic grounds. A compelling history of Bradfield’s proposal reveals many errors and miscalculations. But what the scheme lacked in substance it made up for in grandiose vision.

Water dreaming has been a powerful theme in Australian history. The desire to transform desert into farmland retains appeal and discredited schemes like Bradfield keep reappearing.




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Contempt for nature and country

While less ambitious than the original plan, the “New Bradfield” scheme still engineers against the gradient of both history and nature. It would have irreversible consequences for Queensland’s environment, society and culture.

What’s more, the new scheme manifests much the same mindset as the old.

It’s an attitude that privileges the conquest of nature: in this case literally up-ending geography by turning east-flowing rivers westward. Its celebration of the human struggle against defiant nature reprises the pioneering ethos.

Like many pioneers, “New Bradfield” proposals disregard the interests and land-management practices of Indigenous people. The bushfires ravaging the eastern states show the folly of ignoring traditional ways of caring for country .

Overlooking native title realities can also cost governments and communities.




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Polarising debate neglects more viable projects

“New Bradfield” is promoted as “an asset owned by all Queenslanders for all Queenslanders”. But environmental destruction and disputes over water sales in the Murray-Darling Basin sound a warning.

The Queensland Farmers Federation has cautiously welcomed the new scheme. Others have dismissed it as a “pipe dream”.

Thus, northern Australia again sits amid a polarised debate about its utility to the nation. Such polarising contests diminish the likelihood of more viable projects being implemented.

Extravagant expectations of “untapped” northern resources have been proffered for nearly two centuries. Distant governments have fantasised the Australian tropics as a land of near-limitless potential. Northern communities have many times been disappointed by the results.

Today’s promises to “drought-proof” large areas of Queensland rely on similar images. “Drought-proofing” aims to keep people on the land but often defies economic and social reality.




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Dam developments have an underwhelming record

The “New Bradfield” rhetoric echoes the inflated expectations of myriad disappointing northern development plans in the past. The Ord River project was touted as an agricultural wonder that would put hundreds of thousands of farmers into the Kimberley. Its success lies forever just over the horizon.

Much closer to the present proposal is the Burdekin Falls Dam. It sits in the lower reaches of the same river earmarked for the Hells Gates Dam that would feed the “New Bradfield” scheme. Damming Hells Gates has been advocated since at least the 1930s and has new supporters.

The proposed site for Hells Gates Dam is on Gugu Badhun country on the Burdekin River.
Dr Theresa Petray, Author provided

Back in the 1950s, damming the Burdekin was expected to generate hydro-electric power and irrigate vast swathes of farmland. After decades of political squabbling, the dam was completed in 1988. It does not generate hydro power. Although it irrigates some land downstream, the anticipated huge agricultural expansion never happened.

The Burdekin Falls Dam has helped the regional economy and could help to overcome the water shortages of the nearby city of Townsville. But it has not met the inflated expectations widely proffered decades earlier. The benefits that would flow from another dam further upstream are likely to be even more meagre.




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Grandiose visions of northern development have a habit of failing. A “New Bradfield” scheme, animated by an old pioneering ethos, is unlikely to be different.

Drought-affected communities would derive more benefit from sober proposals that acknowledge the past, integrate Indigenous knowledge and incorporate agricultural innovation.The Conversation

Patrick White, PhD Candidate in History and Politics, James Cook University and Russell McGregor, Adjunct Professor of History, James Cook University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

What the US defence industry can tell us about how to fight climate change



The GPS system of global positioning satellites is just one of the innovations that have sprung from the US military and transformed our lives.
Shutterstock

David C Mowery, University of California, Berkeley

Achieving the large-scale cuts in greenhouse gas emissions that will be needed will require the development and adoption of new technologies at a rate not seen since the information technology revolution.

Which presents a fairly obvious idea. Why not do what we did in the information technology revolution?

There’s no mystery about what that was.

The IT revolution was sparked by the work of the US defence department and associated agencies in three related fields: semiconductors, computer hardware, and computer software.

More recently it has spawned the system of GPS global positioning satellites that can give us a readout on our locations wherever we are.




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The lessons from how the US military industrial complex transformed information technology throughout the world can tell us a lot – but not everything – about what might succeed in stalling climate change.

It did it by spending a huge amount on research and development in its own right (as much as 80% of all government R&D spending during the late 1950s) and acting as a “lead customer,” for early and often very costly versions of technologies developed by private firms, enabling them to improve their innovations over time.

Seeds sown during the cold war

The improvements reduced costs and enhanced reliability, facilitating their penetration into civilian markets.

The US made the money available because of the cold war. Universities were also harnessed for the task, training the scientists and engineers who later assumed key leadership roles in emerging R&D enterprises.

As well, similarities in the technologies and operating environments of early military and civilian versions of new information technology products meant civilian markets for many of them expanded rapidly.

The defence programs also had a “pro-competition” bias.




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New firms played important roles as suppliers of innovations such as integrated circuits, and – in a series of largely coincidental developments – the rigorous enforcement of US antitrust laws meant potentially dominant firms as IBM or AT&T found it hard to impede others.

As a result, intra-industry diffusion of technical knowledge occurred rapidly, complementing high levels of labour mobility within the emerging sector.

The very success of these military research and development programs in spawning vibrant industries means defence markets now account for a much smaller share of the demand for IT products than they did at the time.

Today’s challenges are different…

Climate change is different from post-war research and development in that it is as much an issue of technological substitution as development.

The urgency of the challenge will require the blending of support for the development of new technological solutions with support for the accelerated adoption of existing solutions, such as replacing coal-fired electricity generation with renewable generation.

“Stranded assets” such as abandoned coal-fired power stations and related political and economic challenges will loom large.




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The geographic and technological breadth of the responses needed to limit climate change also dwarf that faced by the US defence establishment during the Cold War.

Also different is the fact that the prospective users of new technologies are by and large not the funders or developers of it. When US defence-related agencies acted as “venture capitalists,” beginning in the 1950s, they were focused primarily on supporting their own needs.

…but there are lessons we can learn

There are some things the diffusion of defence-related information technology can tell us.

One is the importance of rapid adoption.

Much of the large-scale investment in technology improvement and deployment will be the responsibility of private firms. They will require policies that create supportive, credible signals that their innovations will have a market – policies such as carbon taxes.

Another is that what’s needed is a program of research and development that spans an array of institutions throughout the developing and industrial economies.

Yet another is the importance of policies that encourage competition and co-operation among innovators rather than patent wars.

The success of the US military industrial complex in creating one revolution provides pointers to (but not a complete guide to) the next.


Emeritus Professor David C. Mowery will be presening the Tom Spurling Oration at Swinburne University on Wednesday 27 November at 5.45pm.The Conversation

David C Mowery, Professor Emeritus of New Enterprise Development, University of California, Berkeley

This article is republished from The Conversation under a Creative Commons license. Read the original article.