Ships moved more than 11 billion tonnes of our stuff around the globe last year, and it’s killing the climate. This week is a chance to change



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Christiaan De Beukelaer, University of Melbourne

The shipping of goods around the world keeps economies going. But it comes at an enormous environmental cost – producing more CO₂ than the aviation industry. This problem should be getting urgent international attention and action, but it’s not.

This week, all 174 member states of the International Maritime Organisation (IMO) will discuss a plan to meet an emissions reduction target. But the target falls far short of what’s needed, and the plan to get there is also weak.

As other industries clean up their act, shipping’s share of the global emissions total will only increase. New fuels and ship design, and even technology such as mechanical sails, may go some way to decarbonising the industry – but it won’t be enough.

It’s high time the international shipping industry radically curbed its emissions. The industry must set a net-zero target for 2050 and a realistic plan to meet it.

Cargo ships waiting offshore with plane wing in foreground
The shipping industry accounts for more carbon emissions than aviation.
Shutterstock

Shipping: by the numbers

Globally, more than 50,000 merchant ships ship about 11 billion tonnes of goods a year. In 2019 they covered nearly 60 trillion tonne-miles, which refers to transporting one tonne of goods over a nautical mile.

Per tonne-mile, carbon dioxide emissions from shipping are among the lowest of all freight transport options. But in 2018, shipping still emitted 1,060 million tonnes of CO₂ – 2.89% of global emissions. By comparison, the aviation industry contributed 918 million tonnes of CO₂, or 2.4% of the total.

And as international trade increases and other sectors decarbonise, global shipping is expected to contribute around 17% of human-caused emissions by 2050.

An emissions pariah

The IMO, which regulates the global shipping industry, did not set meaningful emissions reduction targets until April 2018. This is despite being requested to reduce emissions as far back as 1997 under the Kyoto Protocol.

The IMO has pledged to halve shipping emissions between 2008 and 2050 while aiming for full decarbonisation. By 2030, the carbon intensity (or emissions per tonne-mile) of individual ships should fall by 40%, compared with 2008 levels.

The IMO’s Marine Environment Protection Committee, is devising binding rules for the industry to achieve these emissions goals. Draft measures being considered this week focus solely on reducing the carbon intensity of individual ships. The plan has been slammed by critics because emissions reductions are not in line with Paris Agreement commitments of limiting global warming to 1.5℃ or 2℃ by 2100.




Read more:
The shipping sector is finally on board in the fight against climate change


There are two main issues with the 40% emissions intensity target.

First, it’s not ambitious enough. Research suggests limiting warming to 1.5℃ requires the shipping industry to reach net-zero emissions. Merely reducing the carbon intensity of ships will barely make a dent in current emissions. Worse, even the best-case scenario will likely lead to a 14% emissions increase compared to 2008.

Second, the IMO has yet to say how it will meet its targets. The plan up for discussion this week is weak: not least because it lacks enforcement mechanisms.

Exterior of IMO building
The IMO dragged its feet on setting an emissions target for the industry.
Shutterstock

So how do we fix the problem?

Earlier this year, I sailed on the Avontuur. This 100-year-old two-masted schooner under German flag sailed from Germany to the Caribbean and Mexico to load 65 tonnes of coffee and cacao, then ship it under sail to Hamburg.

The round-trip took more than six months and 15 crew members. Roughly 169 million ships like the Avontuur would be needed to transport the 11 billion tonnes of goods moved by sea each year. It would require 2.5 billion crew, compared with 1.5 million today. Clearly, that is not realistic.

So how, then, do we solve the international shipping problem? Clean transport advocates say we must reduce demand for cargo transport by using what’s locally available, and generally consuming less and moving to a post-growth economy.




Read more:
Plain sailing: how traditional methods could deliver zero-emission shipping


Some scientists concur, arguing either carbon intensity or shipping demand must come down – and probably both.

Ships can significantly reduce their emissions simply by slowing down. Carbon emissions increase exponentially when ships travel above cruising speed. But the industry seems unwilling to pick this low-hanging fruit, perhaps because it would compromise just-in-time supply chains.

Ships commonly burn huge amounts of heavy fuel oil. Emerging fuels, such as hydrogen and ammonia, have the potential to cut emissions from ships. But producing these fuels may create substantial emissions, and adopting new fuels would require building new ships or retrofitting existing ones.

Existing vessels can also be retrofitted with more efficient propulsion mechanisms. They could also be fitted with wind-assist technologies such as sails, rotors, kites, and suction wings. Research suggests these technologies could reduce a ship’s emissions by 10–60%.

And new designs for sail-powered cargo vessels are emerging. But these ships are yet to be built and it may be a long time before they are widely used.

An artist impression of the Neoline sail-powered cargo ship.
Sail-powered cargo vessels can help slash global emissions.
Neoline

Looking ahead

Technological solutions on their own will not bring the necessary emissions reductions. New technologies must be embraced immediately, and ambitious regulation is necessary. Industry and consumer demand for shipped goods must fall as well.

Earth’s remaining carbon budget is fast shrinking and all industry sectors must do their fair share. At this point in the climate crisis, further delays and weak targets are inexcusable.The Conversation

Christiaan De Beukelaer, Senior Lecturer, University of Melbourne

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

Climate explained: does building and expanding motorways really reduce congestion and emissions?



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Simon Kingham, University of Canterbury


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


Q: Does building and expanding motorways really reduce congestion and emissions, or does it increase it?

Historically, building more and wider roads, including motorways, was seen as a way of reducing congestion. This in turn is supposed to lower emissions.

The new motorways of the future.

Fuel efficiency is optimised for driving at around 80kmh and it decreases the faster you go above that. But with speed limits up to 110kmh, people are likely to drive above 80kmh on motorways — and this means building and expanding motorways will actually increase emissions.

Many countries, especially in Europe, are now looking to lower speed limits partly to reduce emissions.




Read more:
Remove car lanes, restrict vehicles and improve transit to reduce traffic congestion


In addition to speeding, rapid acceleration and braking can lower mileage by 15-30% at highway speeds and 10-40% in stop-and-go traffic. If building or expanding motorways did reduce congestion, the smoother driving would be a benefit.

But this assumption is not backed by evidence. Research shows even on roads with no impediments drivers brake and accelerate unnecessarily, increasing congestion and emissions.

One of the arguments for future autonomous vehicles is that such braking and accelerating should not occur and emissions should reduce.

New roads, new drivers

The most significant impact new and expanded motorways have on congestion and emissions is the effect on the distance people travel.

Historically, engineers assumed cars (and more pertinently their drivers) would behave like water. In other words, if you had too much traffic for the road space provided, you would build a new road or expand an existing one and cars would spread themselves across the increased road space.

A traffic jam on a motorway to Auckland.
Congested traffic on a motorway into the centre of Auckland.
patjo/Shutterstock

Unfortunately, this is not what happens. New road capacity attracts new drivers. In the short term, people who had previously been discouraged from using congested roads start to use them.

In the longer term, people move further away from city centres to take advantage of new roads that allow them to travel further faster.

This is partly due to the “travel time budget” — a concept also known as Marchetti’s constant — which suggests people are prepared to spend around an hour a day commuting. Cities tend to grow to a diameter of one-hour travel time.

City sprawl

The concept is supported by evidence that cities have sprawled more as modes of transport have changed. For example, cities were small when we could only walk, but expanded along transport corridors with rail and then sprawled with the advent of cars. This all allows commuters to travel greater distances within the travel time budget.

Building or expanding roads releases latent demand — widely defined as “the increment in new vehicle traffic that would not have occurred without the improvement of the network capacity”.

This concept is not new. The first evidence of it can be found back in the 1930s. Later research in 1962 found that “on urban commuter expressways, peak-hour traffic congestion rises to meet maximum capacity”.

A considerable body of evidence is now available to confirm this. But, despite this indisputable fact, many road-improvement decisions continue to be based on the assumption that extra space will not generate new traffic.

If you build it, they will drive

A significant change occurred in 1994 when a report by the UK Advisory Committee on Trunk Road Appraisal confirmed road building actually generates more traffic.

In New Zealand, this wasn’t acknowledged until the Transport Agency’s 2010 Economic Evaluation Manual, which said:

[…] generated traffic often fills a significant portion (50–90%) of added urban roadway capacity.

Vehicle lights blur at night on a busy motorway into Auckland.
Traffic increases as motorways expand.
Shaun Jeffers/Shutterstock

Some congestion discourages people from driving (suppresses latent demand), but with no congestion traffic will fill road space over time, particularly in or near urban areas.

Interestingly, the opposite can also work. Where road space is removed, demand can be suppressed and traffic reduces without other neighbouring roads becoming overly congested.




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Climate explained: could electric car batteries feed power back into the grid?


One of the best examples of this is the closure of the Cheonggyecheon Freeway in the middle of Seoul, South Korea.

When the busy road was removed from the city, rather than the traffic moving to and congesting nearby roads, most of the traffic actually disappeared, as Professor Jeff Kenworthy from Curtin University’s Sustainable Policy Institute notes.

This suppression of latent demand works best when good alternative ways of travel are available, including high-quality public transport or separated cycle lanes.

The short answer to the question about road building and expansion is that new roads do little to reduce congestion, and they will usually result in increased emissions.The Conversation

Simon Kingham, Professor, University of Canterbury

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

High-speed rail on Australia’s east coast would increase emissions for up to 36 years



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Greg Moran, Grattan Institute

Bullet trains are back on the political agenda. As the major parties look for ways to stimulate the economy after the COVID-19 crisis, Labor is again spruiking its vision of linking Melbourne, Sydney, Canberra and Brisbane with high-speed trains similar to the Eurostar, France’s TGV or Japan’s Shinkansen.

In 2013 when Labor was last in government, it released a detailed feasibility study of its plan. But a Grattan Institute report released today shows bullet trains are not a good idea for Australia. Among other shortcomings, we found an east coast bullet train would not be the climate saver many think it would be.

Anthony Albanese releasing a high-speed rail study in 2013. The idea has long been mooted.
AAP/Lukas Coch

The logic seems simple enough

Building a bullet train to put a dent in our greenhouse gas emissions has been long touted. The logic seems simple – we can take a lot of planes and their carbon pollution out of the sky if we give people another way to get between our largest cities in just a few hours or less.

And this is all quite true, as the chart below shows. We estimate a bullet train’s emissions per passenger-kilometre on a trip from Melbourne to Sydney would be about one-third of those of a plane. We calculated this using average fuel consumption estimates from 2018 for various types of transport, as well as the average emissions intensity of electricity generated in Australia in 2018.




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If we use the projected emissions intensity of electricity in 2035 – the first year trains were expected to run under Labor’s original plan – the fraction drops to less than one-fifth of a plane’s emissions in 2018.

It should be remembered that while coaches might be the most climate-friendly way to travel long distances, they can’t compete with bullet trains or planes for speed.


Notes: Average occupancy estimates are 38.5 (coach), 320 (bullet train), 119 (conventional rail), 2.26 (car), and 151.96 (plane). Plane emissions include radiative forcing. For more detail, see ‘Fast train fever: Why renovated rail might work but bullet trains won’t’.

There’s a catch

So, where’s the problem? It lies in construction. A bullet train along Australia’s east coast would take about 15 years of planning, then would be built in sections over about 30 years. This construction would generate huge emissions.

In particular, vast emissions would be released in the production of steel and concrete required to build a train line from Melbourne to Brisbane. These so-called “scope 3” emissions can account for 50-80% of total construction emissions.




Read more:
Look beyond a silver bullet train for stimulus


Scope 3 emissions are sometimes not counted when assessing the emissions impact of a project, but they should be. There’s no guarantee the quantities of concrete and steel in question would have been produced and used elsewhere if not for the bullet train.

And the long construction time means it would be many years before the train actually starts to take planes out of the sky. This, combined with construction emissions, means a bullet train would be very slow to reduce emissions. In fact, we found it would first increase emissions for many years.

Slow emissions benefit

As the chart below shows, we estimate building the bullet train could lead to emissions being higher than they otherwise would’ve been for between 24 and 36 years.

This period would start at year 15 of the project, when planning ends and construction starts. At the earliest, it would end at year 39. This is the point at which some sections of the project would be complete, and at which enough trips have been taken (and enough plane or car trips foregone) that avoided emissions overtake emissions created.

This means the train might not actually create a net reduction in emissions until almost 40 years after the government commits to building it – and even this is under a generously low estimate of scope 3 emissions. If scope 3 emissions are on the high side, emission reductions may not start until just after the 50-year mark – 36 years after construction began.


Notes: Estimates derived from the 2013 feasibility study of the Melbourne-to-Brisbane bullet train, and other sources. The feasibility study assumed that government would commit to the project in 2013. For more detail, see ‘Fast train fever: Why renovated rail might work but bullet trains won’t’.

The bullet train would create a net reduction in emissions from the 40- or 50-year mark onwards. But the initial timelines matter.

The world needs to achieve net zero emissions by about 2050 if we’re to avoid the worst impacts of climate change. All Australian states and territories have made this their goal. Unfortunately, a bullet train will not help us achieve it.

The way forward

Hitting the 2050 net-zero emissions target implicit in the Paris Agreement remains a daunting but achievable task. Decarbonising transport will play a big part, including the particularly tricky question of reducing aviation emissions.

But during the most crucial time for action on emissions reduction, a bullet train will not help. Our efforts and focus ought to be directed elsewhere.

Milan Marcus assisted in the preparation of this piece.




Read more:
Delays at Canberra: why Australia should have built fast rail decades ago


The Conversation


Greg Moran, Senior Associate, Grattan Institute

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

Climate explained: why switching to electric transport makes sense even if electricity is not fully renewable



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Robert McLachlan, Massey University

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

I have a question about the charging of electric cars. I understand New Zealand is not 100% self-sufficient in renewable energy (about 80%, supplemented by 20% generally produced by coal-fired stations). If I were to buy an electric vehicle it would add to the load on the national grid. Is the only way we are currently able to add the extra power to burn more coal? Does this not make these vehicles basically “coal fired”?

New Zealand is indeed well supplied with renewable electricity. In recent years, New Zealand has averaged 83% from renewable sources (including 60% hydropower, 17% geothermal, and 5% wind) and 17% from fossil fuels (4% coal and 13% gas).

In addition to being cheap and renewable, hydropower has another great advantage. Its production can ramp up and down very quickly (by turning the turbines on and off) during the day to match demand.

Looking at a typical winter’s day (I’ve taken July 4, 2018), demand at 3am was 3,480 megawatts (MW) and 85% was met by renewable sources. By the early evening peak, demand was up to 5,950MW, but was met by 88% renewable sources. Fossil fuel sources did ramp up, but hydropower ramped up much more.

Flipping the fleet

Even during periods of peak demand, our electricity is very clean. An electric vehicle (EV) charged during the evening would emit about 20 grams of carbon dioxide per kilometre.

Even an EV charged purely on coal- or gas-fired electricity still has lower emissions than a petrol or diesel car, which comes to around 240g CO₂/km (if one includes the emissions needed to extract, refine, and transport the fuel).

An EV run on coal-fired electricity emits around 180g CO₂/km during use, while the figure for gas-fired electricity is about 90g CO₂/km. This is possible because internal combustion engines are less efficient than the turbines used in power stations.




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Climate explained: the environmental footprint of electric versus fossil cars


Looking longer term, a mass conversion of transport in New Zealand to walking, cycling and electric trains, buses, cars and trucks is one of the best and most urgent strategies to reduce emissions. It will take a few decades, but on balance it may not be too expensive, because of the fuel savings that will accrue (NZ$11 billion of fuel was imported in 2018.)

This conversion will increase electricity use by about a quarter. To meet it we can look at both supply and demand.

More renewable electricity

On the supply side, more renewable electricity is planned – construction of three large wind farms began in 2019, and more are expected. The potential supply is significant, especially considering that, compared to many other countries, we’ve hardly begun to start using solar power.

But at some point, adding too much of these intermittent sources starts to strain the ability of the hydro lakes to balance them. This is at the core of the present debate about whether New Zealand should be aiming for 100% or 95% renewable electricity.

There are various ways of dealing with this, including storage batteries, building more geothermal power stations or “pumped hydro” stations. In pumped hydro, water is pumped uphill into a storage lake when there is an excess of wind and solar electricity available, to be released later. If the lake is large enough, this technology can also address New Zealand’s persistent risk of dry years that can lead to a shortage of hydropower.




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Smarter electricity use

On the demand side, a survey is under way to measure the actual charging patterns of EV drivers. Information available so far suggests that many people charge their EV late at night to take advantage of cheap night rates.

If demand gets too high at certain times, then the cost of both generation and transmission will likely rise. To avoid this, electricity suppliers are exploring smart demand responses, based on the hot water ripple control New Zealand began using in the 1950s. This allows electricity suppliers to remotely turn off hot water heaters for a few hours to limit demand.

In modern versions, consumers or suppliers can moderate demand in response to price signals, either in real time using an app or ahead of time through a contract.

New Zealand’s emissions from land transport continue to rise, up by another 2% in 2018 and almost double on 1990 levels.

To address climate change, we have to stop burning fossil fuels. Passenger cars are among the biggest users and also one of the easiest to change. Fossil fuel cannot be recycled or made clean. In contrast, electricity is getting cleaner all the time, both in New Zealand and in car factories.

If you switch to an EV now, your impact is far greater than just your personal reduction in emissions. Early adopters are vital. The more EVs we have, the more people will get used to them, the easier it will be to counter misinformation, and the more pressure there will be to cater for them.

Many people have found that switching to an electric car has been empowering and has galvanised them to start taking other actions for the climate.The Conversation

Robert McLachlan, Professor in Applied Mathematics, Massey University

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

Transport is letting Australia down in the race to cut emissions



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Philip Laird, University of Wollongong

At a time Australia is meant to be reducing its greenhouse emissions, the upward trend in transport sector emissions continues. The latest National Greenhouse Gas Inventory report released last week shows the transport sector emitted 102 million tonnes (Mt) of carbon dioxide equivalent (MtCO₂-e) in the 12 months to September 2019. This was 18.9% of Australia’s emissions.

Overall, the trend in emissions from all sectors have been essentially flat since 2013. If Australia is to reduce emissions, all sectors including transport must pull their weight.




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Overall trend emissions, by quarter, September 2009 to September 2019.
National Greenhouse Gas Inventory

Transport emissions have gone up 64% since 1990. That’s the largest percentage increase of any sector.

Transport emissions, actual and trend, by quarter, September 2009 to September 2019.
Source: National Greenhouse Gas Inventory

Transport sector emissions include the direct burning of fuels for road, rail, domestic aviation and domestic shipping, but exclude electricity for electric trains.

Transport emissions are now equal second with stationary energy (fuels consumed in the manufacturing, construction and commercial sectors and heating) at 18.9%. The electricity sector produces 33.6% of all emissions. The main reasons for transport emissions trending upwards are an over-dependence on cars with high average fuel use and an over-reliance on energy-intensive road freight.

Inevitable results of policy failure

Increasing transport emissions are a result of long-standing government policies on both sides of politics. In 2018, the Climate Council noted:

Australia’s cars are more polluting; our relative investment in and use of public and active transport options is lower than comparable countries; and we lack credible targets, policies, or plans to reduce greenhouse gas pollution from transport.

John Quiggin and Robin Smit recently wrote about vehicle fuel efficiency for The Conversation. They cited new research that indicates emissions from road transport will accelerate. This is largely due to increased sales of heavier vehicles, such as four-wheel drives, and diesel cars.




Read more:
We thought Australian cars were using less fuel. New research shows we were wrong


The government has ignored recommendations to adopt mandatory fuel-efficiency standards for road passenger vehicles. Australia is the only OECD country without such standards.

Research by Hugh Saddler found a marked increase in CO₂ emissions from burning diesel (up 21.7Mt between 2011 and 2018). A 2015 Turnbull government initiative to phase in from 2020 to 2025 a standard of 105g of CO₂ per kilometre for light vehicles was “shelved after internal opposition and criticism from the automotive lobby”.

At the same time, the uptake of electric vehicles is slow. Economist Ross Garnaut, in his 2019 book Superpower: Australia’s Low-Carbon Opportunity, sums it up:

Australia is late in preparation for and investment in electric road transport.




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Clean, green machines: the truth about electric vehicle emissions


Australia’s low transport energy efficiency (and so high CO₂ emissions) has also attracted overseas attention. The American Council for an Energy-Efficient Economy rates the world’s 25 largest energy users for sectors including transportation. In 2018, Australia slipped two places to 18th overall. It was 20th for transportation with just 6.5 points out of a possible 25 on nine criteria.

On four of these criteria, Australia scored zero: fuel economy of passenger vehicles, having no fuel-efficiency standards for passenger vehicles and heavy trucks, and having no smart freight programs.

For vehicle travel per capita, the score was half a point. For three metrics – freight task per GDP, use of public transport, and investment in rail transit versus roads – Australia scored just one point each.

Only in one metric, energy intensity of freight transport, did Australia get full marks. This was a result of the very high energy efficiency of the iron ore railways in Western Australia’s Pilbara region.

The International Monetary Fund (IMF) has also questioned the Australian government’s preference for funding roads rather than more energy-efficient rail transport. The IMF says Australia should be spending more on infrastructure, but this should be on rail, airports and seaports, rather than roads.

What can be done

The first thing is to acknowledge that our preferred passenger transport modes of cars and planes cause more emissions than trains, buses, cycling and walking. For example, CO₂ emissions per passenger km can be 171 grams for a passenger car as against 41g for domestic rail.


Data source: Greenhouse gas reporting: conversion factors 2019

For freight, our high dependence on trucks rather than rail or sea freight increases emissions by a factor of three.




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Labor’s plan for transport emissions is long on ambition but short on details


A 1996 report, Transport and Greenhouse, from what is now the federal Bureau of Infrastructure, Transport and Regional Economics (BITRE), reviewed no fewer than 16 measures (including five “no regrets” measures) to cut transport emissions. In a 2002 report, Greenhouse Policy Options for Transport, BITRE offered 11 measures to reduce vehicle kilometres travelled (VKT), nine measures to reduce emissions per VKT, and four road-pricing measures (mass-distance charges for heavy trucks, tolls, internalising transport externalities and emission charging).

BITRE last appeared to revisit this important issue in a 2009 report on transport emission projections to 2020. This report projected a total of 103.87Mt CO₂-e for 2019. Actual 2019 transport emissions will be about 102Mt.

It’s important to note that BITRE’s 2009 projection was on a business-as-usual basis. The current level of about 4 tonnes a year per person is where Australia was in 2000.

Clearly, Australia needs to do better. As well as the BITRE remedies, another remedy would be to adopt a 2002 National Action Plan approved by the Australian Transport Council in collaboration with the Commonwealth, state and territory governments. The plan included, within ten years, “programs that encourage people to take fewer trips by car” and a shift “from predominantly fixed to predominantly variable costs” to “ensure that transport users experience more of the true cost of their travel choices”. This did not proceed.

However, New Zealand has effectively adopted this approach for many years. Petrol excise is now 66.524 cents per litre (just 42.3c/l in Australia) and the revenue goes to the National Land Transport Fund for roads and alternatives to roads, resulting also in lower registration fees for cars. New Zealand has had mass distance pricing for heavy trucks for 40 years. These measures have not stopped its economy performing well.

Why do measures that would reduce transport emissions continue to be so elusive in Australia?The Conversation

Philip Laird, Honorary Principal Fellow, University of Wollongong

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

Major airlines say they’re acting on climate change. Our research reveals how little they’ve achieved


Susanne Becken, Griffith University

If you’re a traveller who cares about reducing your carbon footprint, are some airlines better to fly with than others?

Several of the world’s major airlines have announced plans to become “carbon neutral”, while others are trialling new aviation fuels. But are any of their climate initiatives making much difference?

Those were the questions we set out to answer a year ago, by analysing what the world’s largest 58 airlines – which fly 70% of the total available seat-kilometres – are doing to live up to their promises to cut their climate impact.

The good news? Some airlines are taking positive steps. The bad news? When you compare what’s being done against the continued growth in emissions, even the best airlines are not doing anywhere near enough.

More efficient flights still drive up emissions

Our research found three-quarters of the world’s biggest airlines showed improvements in carbon efficiency – measured as carbon dioxide per available seat. But that’s not the same as cutting emissions overall.

One good example was the Spanish flag carrier Iberia, which reduced emissions per seat by about 6% in 2017, but increased absolute emissions by 7%.



For 2018, compared with 2017, the collective impact of all the climate measures being undertaken by the 58 biggest airlines amounted to an improvement of 1%. This falls short of the industry’s goal of achieving a 1.5% increase in efficiency. And the improvements were more than wiped out by the industry’s overall 5.2% annual increase in emissions.

This challenge is even clearer when you look slightly further back. Industry figures show global airlines produced 733 million tonnes of CO₂ emissions in 2014. Falling fares and more people around wanting to fly saw airline emissions rise 23% in just five years.

What are the airlines doing?

Airlines reported climate initiatives across 22 areas, with the most common involving fleet renewal, engine efficiency, weight reductions and flight path optimisation. Examples in our paper include:

  • Singapore Airlines modified the Trent 900 engines on their A380 aircraft, saving 26,326 tonnes of CO₂ (equivalent to 0.24% of the airline’s annual emissions);
  • KLM’s efforts to reduce weight on board led to a CO₂ reduction of 13,500 tonnes (0.05% of KLM’s emissions).
  • Etihad reports savings of 17,000 tonnes of CO₂ due to flight plan improvements (0.16% of its emissions).


Nineteen of the 58 large airlines I examined invest in alternative fuels. But the scale of their research and development programs, and use of alternative fuels, remains tiny.

As an example, for Earth Day 2018 Air Canada announced a 160-tonne emissions saving from blending 230,000 litres of “biojet” fuel into 22 domestic flights. How much fuel was that? Not even enough to fill the more than 300,000-litre capacity of just one A380 plane.

Carbon neutral promises

Some airlines, including Qantas, are aiming to be carbon neutral by 2050. While that won’t be easy, Qantas is at least starting with better climate reporting; it’s one of only eight airlines addressing its carbon risk through the systematic Task Force on Climate-related Financial Disclosures process.

About half of the major airlines engage in carbon offsetting, but only 13 provide information on measurable impacts. Theses include Air New Zealand, with its FlyNeutral program to help restore native forest in New Zealand.

That lack of detail means the integrity of many offset schemes is questionable. And even if properly managed, offsets still avoid the fact that we can’t make deep carbon cuts if we keep flying at current rates.




Read more:
Flight shame won’t fix airline emissions. We need a smarter solution


What airlines and governments need to do

Our research shows major airlines’ climate efforts are achieving nowhere near enough. To decrease aviation emissions, three major changes are urgently needed.

  1. All airlines need to implement all measures across the 22 categories covered in our report to reap any possible gain in efficiency.

  2. Far more research is needed to develop alternative aviation fuels that genuinely cut emissions. Given what we’ve seen so far, these are unlikely to be biofuels. E-fuels – liquid fuels derived from carbon dioxide and hydrogen – may provide such a solution, but there are challenges ahead, including high costs.

  3. Governments can – and some European countries do – impose carbon taxes and then invest into lower carbon alternatives. They can also provide incentives to develop new fuels and alternative infrastructure, such as rail or electric planes for shorter trips.

How you can make a difference

Our research paper was released late last year, at a World Travel and Tourism Council event linked to the Madrid climate summit. Activist Greta Thunberg famously sailed around the world to be there, rather than flying.

Higher-income travellers from around the world have had a disproportionately large impact in driving up aviation emissions.



This means that all of us who are privileged enough to fly, for work or pleasure, have a role to play too, by:

  1. reducing our flying (completely, or flying less)
  2. carbon offsetting
  3. for essential trips, only flying with airlines doing more to cut emissions.

To really make an impact, far more of us need to do all three.




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


The Conversation


Susanne Becken, Professor of Sustainable Tourism and Director, Griffith Institute for Tourism, Griffith University

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

Shaming people for flying won’t cut airline emissions. We need a smarter solution



Swedish airport operator Swedavia reported passenger numbers at its ten airports in October 2019 were down 5% on the previous year.
http://www.shutterstock.com

Duygu Yengin, University of Adelaide and Tracey Dodd, University of Adelaide

“Fake news”, the chief executive of Lufthansa has called it. But his counterpart at Air France calls it the airline industry’s “biggest challenge”. So does the president of Emirates: “It’s got to be dealt with.”

What they’re talking about is “flight shame” – the guilt caused by the environmental impacts of air travel. Specifically, the carbon emissions.

It’s the reason teen climate-change activist Greta Thunberg refused to fly to New York to address the United Nations Climate Action Summit in September, taking a 14-day sea voyage instead.

A publicity photo of Greta Thunberg on her way to New York aboard the yacht Malizia II in August 2019. The phrase ‘skolstrejk för klimatet’ means school strike for climate.
EPA

In Thunberg’s native Sweden, flight shame (“flygskam”) has really taken off, motivating people to not take off. Last year 23% of Swedes reduced their air travel to shrink their carbon footprint, according to a WWF survey. Swedish airport operator Swedavia reported passenger numbers at its ten airports in October were down 5% on the previous year.

The potency of this guilt is what put Lufthansa’s head, Carsten Spohr, on the defensive at an aviation industry conference in Berlin in November.




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


“Airlines should not have to be seen as a symbol of climate change. That’s just fake news,” he declared. “Our industry contributes 2.8% of global CO₂ emissions. As I’ve asked before, how about the other 97.2%? Are they contributing to global society with as much good as we do? Are they reducing emissions as much as we do?”

Does he have a point? Let’s consider the evidence.

How bad are aviation CO₂ emissions?

The International Council on Clean Transportation (the same organisation that exposed Volkwagen’s diesel emissions fraud), estimates commercial aviation accounted for 2.4% of all carbon emissions from fossil-fuel use in 2018.

So it’s true many other sectors contribute more.

It is also true airlines are making efforts to reduce the amount of carbon they emit per passenger per kilometre. Australia’s aviation industry, for example, has reduced its “emissions intensity” by 1.4% a year since 2013.

However, the ICCT estimates growth in passenger numbers, and therefore total flights, means total carbon emissions from commercial aviation have ballooned by 32% in five years, way faster than UN predictions. On that trajectory, the sector’s total emissions could triple by 2050.

Alternatives to fossil fuels

A revolution in aircraft design could mitigate that trajectory. The International Air Transport Association suggests the advent of hybrid electric aircraft propulsion (similar to how a hybrid car works, taking off and landing using electric power) by about 2030-35 could reduce fossil fuel consumption by up to 40%. Fully electric propulsion after that could eliminate fossil fuels completely.




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Even with the advent of electric airliners by mid-century, the huge cost and long lifespan of commercial jets means it could still take decades to wean fleets off fossil fuels.

A shorter-term solution might be replacing fossil fuels with “sustainable aviation fuels” such as biofuels made from plant matter. But in 2018 just 15 million litres of aviation biofuel were produced – less than 0.1% of total aviation fuel consumption. The problem is it costs significantly more than standard kerosene-based aviation fuel. Greater use depends on the price coming down, or the price of fossil fuels going up.

Research into biofuels made from algae and other plant matter could prove a viable alternative to fossil fuels. Right now, though, cost is a major hurdle to uptake.
http://www.shutterstock.com

Pricing carbon

This brings us to the role of economics in decarbonising aviation.

An economist will tell you, for most goods the simplest way to reduce its consumption is to increase its price, or reduce the price of alternatives. This is the basis of all market-based solutions to reduce carbon emissions.

One way is to impose a tax on carbon, the same way taxes are levied on alcohol and tobacco, to deter consumption as well as to raise revenue to pay the costs use imposes on society.

The key problem with this approach is a government must guess at the price needed to achieve the desired reduction in demand. How the tax revenue is spent is also crucial to public acceptance.




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Why our carbon emission policies don’t work on air travel


In France, opposition to higher fuel taxes led the government to instead announce an “eco-tax” on flights.

This proposed tax will range from €1.50 (about A$2.40) for economy flights within the European Union to €18 (about A$29.30) for business-class flights out of the EU. Among those who think this price signal is too low to make any real difference is Sam Fankhauser, director of the Grantham Research Institute on Climate Change and the Environment in London.

Trading and offsets

Greater outcome certainty is the reason many economists champion an emissions trading scheme (also known as “cap and trade”). Whereas a tax seeks to reduce carbon emissions by raising the price of emission, a trading scheme sets a limit on emissions and leaves it to the market to work out the price that achieves it.

One advantage economists see in emissions trading is that it creates both disincentive and incentives. Emitters don’t pay a penalty to the government. They effectively pay other companies to achieve reductions on their behalf through the trade of “carbon credits”.

The European Union already has an emissions trading scheme that covers flights within the European Economic Area, but it has been criticised for limiting incentives for companies to reduce emissions because they can cheaply buy credits, such as from overseas projects such as tree-planting schemes.

Stockholm Arlanda Airport: Swedish data suggests voluntary action motivated by shame is unlikely to lead to any significant reduction in demand for international air travel.
http://www.shutterstock.com

This led to the paradox of scheme delivering a reported 100 million tonnes of “reductions/offsets” from Europe’s aviation sector between 2012 and 2018 even while the sector’s emissions increased.

A better solution might come from a well-designed international trading scheme. The basis for this may be the global agreement known as the Carbon Offsetting and Reduction Scheme for International Aviation. Already 81 countries, representing three-quarters of international aviation activity, have agreed to participate.




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Carbon offsets can do more environmental harm than good


What seems clear is that guilt and voluntary action to reduce carbon emissions has its limits. This is suggested by the data from Sweden, the heartland of flight shame.

Behind the 5% reduction in passenger numbers reported by Swedavia is a major difference between domestic passengers (down 10%) and international passengers (down just 2%). That might have something to do with the limited travel alternatives when crossing an ocean.

For most of us to consider emulating Greta Thunberg by taking a sailboat instead, the price of a flight would have to be very high indeed.The Conversation

Duygu Yengin, Associate Professor of Economics, University of Adelaide and Tracey Dodd, Research Fellow, Adelaide Business School, University of Adelaide

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

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.




Read more:
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.

Own a bike you never ride? We need to learn how to fail better at active transport



Many rarely used bikes end up languishing in the shed.
peace baby/Shutterstock

Glen Fuller, University of Canberra; Gordon Waitt, University of Wollongong; Ian Buchanan, University of Wollongong; Tess Lea, University of Sydney, and Theresa Harada, University of Wollongong

Once upon a time when something was simple to do we said: “It’s as easy as riding a bike.” But switching from driving a car to riding a bike as one’s main means of transport is anything but easy.

The well-documented obstacles holding people back from cycling include a lack of proper bike lanes, secure parking arrangements, end-of-trip facilities and bike-friendly public transport, as well as lack of convenient storage space.




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Despite these obstacles, people continue to try to make cycling a central part of their lives, with varying degrees of success.

While we know broadly what the impediments are, we don’t know how individuals confront them over time. We tend to approach this issue as an “all or nothing” affair – either people cycle or they don’t. Research is often framed in terms of cyclists and non-cyclists.

But, for most people, our research tells us it is a gradual process of transformation, with setbacks as well as small victories. The hesitant maybe-cyclist of today is potentially the fully committed cyclist of tomorrow. Unfortunately, the reverse is also true.

We have taken a lead from research into smoking, which sees failed quit attempts not as failures but as necessary steps on the road to success. Part of our research is interested in the faltering starts people make in transitioning from motor vehicles to bikes. Our aim is to help identify new intervention points for cycling policy.

Cycling enthusiast Samuel Beckett aptly summed up this in Worstward Ho:

Try again. Fail again. Fail better.

Where the bike is kept is telling

Our question is: how can we fail better? Building on research with 58 cyclists in the Wollongong region, we recently shifted our emphasis to another local government area, the City of Sydney.

We focused on people who want to cycle but have mostly failed so far. We carried out in-depth qualitative interviews with 12 participants, following up each with a go-along, where participants guide us through their regular travel routes.

To date, all participants convey good intentions to incorporate cycling into their lives. All say they want to resume cycling, yet none have succeeded.

These bikes near the front door of a student share house are almost certainly ridden often.
cbamber85/Flickr, CC BY

Their attempts were inhibited by commonplace issues: lost confidence in their abilities, less enjoyment of cycling because of congestion, and experiences of a car accident or a near miss.

Our research has found that where bicycles are stored is a reliable indicator of the changing value of the bicycle in an individual’s everyday life. One can pinpoint where someone is in the course of their starting-to-cycle journey by locating where their bike is kept.

When things are going well the bike is near the front door ready for immediate use. As things get difficult, the bike migrates from the front to the back of the house, to languish in a spare room or the shed, before finally being put out on the curb as hard rubbish (or for “freecycling”).




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Storage is a key obstacle

Contrary to interpretations of data indicating inner-city residents are the most likely to cycle, we have found participants who live in small, inner-city dwellings face daunting storage issues that all too often defeat them. They have told us about storing the bicycle inconveniently inside the house, wedged in dining rooms, hallways and bedrooms.

The search for a place to store the bike increased the inconvenience of using it for transport until finally the bike was locked away, kept only as a sign of ongoing intention and hope. This inconvenience defeats successive start attempts before they’re seriously able to be revived.

Lack of convenient storage is a serious obstacle to becoming a regular bike rider.
Author provided

For example, Greg (37) confirms the “pain” of poor storage options discourages him from riding more regularly:

So it’s called the room under the stairs, according to the real estate agent. I don’t know how … And that’s partly the pain of taking it out. I would take it out more often, but every time I have to take it out I have to delicately wheel it here where you are. And sometimes scratch the wall, and then out through the door and gate … I would keep it outside, but my partner won’t let me because he thinks it will be stolen. I would ride more if it was just there, and I’d hop on and off.“

Urban design for convenience matters

The languishing bike prompts us to ask questions about the urban design of convenience. It’s a key element of any active transport policy that aims to promote cycling and walking.

Something as simple as lockable bike hangars on residential streets might liberate intentions into actions. Such facilities would be everyday visual reminders to cycle and an added symbol that cars are not the only way of occupying roads.

Bicycle lockers on the street, like these ones in Dublin, Ireland, are a visible sign of a cycle-friendly culture.
Arnieby/Shutterstock



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We invite others who have started this journey to share and celebrate their stories of failing better, particularly those in the City of Sydney, by participating in our research.The Conversation

Glen Fuller, Associate Professor Communications and Media, University of Canberra; Gordon Waitt, Professor of Geography, University of Wollongong; Ian Buchanan, Professor of Cultural Studies, University of Wollongong; Tess Lea, Associate Professor, Gender and Cultural Studies, University of Sydney, and Theresa Harada, Research Fellow at Australian Centre for Culture, Environment, Society and Space, University of Wollongong

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

Feeling flight shame? Try quitting air travel and catch a sail boat



Regina Maris, the ship activists will sail to a climate conference in Chile.
Sail to the COP

Christiaan De Beukelaer, University of Melbourne

If you’ve caught a long haul flight recently, you generated more carbon emissions than a person living in some developing countries emits in an entire year.

If that fact doesn’t ruffle you, consider this: worldwide, 7.8 billion passengers are expected to travel in 2036 – a near doubling of current numbers. If business as usual continues, one analysis says the aviation sector alone could emit one-quarter of the world’s remaining carbon budget – the amount of carbon dioxide emissions allowed if global temperature rise is to stay below 1.5℃.

The world urgently needs a transport system that allows people to travel around the planet without destroying it.

A group of European climate activists are sending this message to world leaders by sailing, rather than flying, to a United Nations climate conference in Chile in December.

The Sail to the COP initiative follows Greta Thunberg’s high-profile sea voyage to attend last month’s United Nations climate summit in New York. The activists are not arguing global yacht travel is the new normal – in fact therein lies the problem. We need to find viable alternatives to fossil-fuelled air travel, and fast.

Greta Thunberg onboard the racing boat Malizia II in the Atlantic Ocean on her journey to New York last month.
AAP



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Why aviation emissions matter

A study conducted for the European Parliament has warned that if action to reduce flight emissions is further postponed, international aviation may be responsible for 22% of global carbon emissions by 2050 – up from about 2.5% now. This increasing share would occur because aviation emissions are set to grow, while other sectors will emit less.

In Australia, aviation underpins many aspects of business, trade and tourism.

The below image from global flight tracking service Flightradar24 shows the number of planes over Australia at the time of writing.

A screen shot from Flightradar24 showing the flights over Australia at the time of writing.
Flightradar24

Federal government figures show the civil aviation sector, domestic and international, contributed 22 million tonnes of carbon dioxide-equivalent emissions in 2016.

The number of passenger movements from all Australian airports is set to increase by 3.7% a year by 2030-31, to almost 280 million.

To change, start with a jet fuel tax

While airlines are taking some action to cut carbon emissions, such as introducing newer and more fuel efficient aircraft, the measures are not enough to offset the expected growth in passenger numbers. And major technological leaps such as electric aircraft are decades away from commercial reality.

Emissions from international flights cannot easily be attributed to any single country, and no country wants to count them as their own. This means that international civil aviation is not regulated under the Paris Agreement. Instead, responsibility has been delegated to the International Civil Aviation Organisation (ICAO).




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The Sail to the COP initiative is calling for several actions. First, they say jet fuel should be taxed. At present it isn’t – meaning airlines are not paying for their environmental damage. This also puts more sustainable transport alternatives, which do pay tax, at a disadvantage.

Research suggests a global carbon tax on jet fuel would be the most efficient way to achieve climate goals.

But instead, in 2016 ICAO established a global scheme for carbon offsetting in international aviation. Under the plan, airlines will have to pay for emissions reduction in other sectors to offset any increase in their own emissions after 2020.




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Greta Thunberg made it to New York emissions-free – but the ocean doesn’t yet hold the key to low-carbon travel


Critics say the strategy will not have a significant impact – pointing out, for example, that the aviation industry is aiming to only stabilise its emissions, not reduce them.

In contrast, the international shipping sector has pledged to halve its emissions by 2050, based on 2008 levels. Some small shipping companies are even using zero-emissions sail propulsion as a sustainable means of cargo transport.

Sail to the COP is also seeking to promote other sustainable ways of travelling such as train, boat, bus or bike. It says aviation taxes are key to this, because it would encourage growth in other transport modes and make it easier for people to to make a sustainable transport choice.

A growing number of people around the world are already making better choices.
In Thunberg’s native Sweden for example, the term “flygskam” – or flight shame – is used to describe the the feeling of being ashamed to take a flight due to its environmental impact. The movement has reportedly led to a rising number of Swedes catching a train for domestic trips.

Can we sail beyond nostalgia?

Many will dismiss the prospect of a revival in sea travel as romantic but unrealistic. And to some extent they are right. Sailing vessels cannot meet current demand in terms of speed or capacity. But perhaps excessive travel consumption is part of the problem.

The late sociologist John Urry has outlined a number of possible futures in a world of oil scarcity.

One is a shift to a low-carbon, and low-travel, society, in which we would “live smaller, live closer, and drive less”. Urry argues we may be less rich, but not necessarily less happy.

Meantime, the challenges for passenger ocean travel remain many. Not least, it can be slow and uncomfortable – Thunberg likened it to “camping on a rollercoaster”.




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But one Sail to the COP organiser, Jeppe Bijker, thinks it’s an option worth exploring. He developed the Sailscanner tool where users can check if sailing ships are taking their desired route, or request one.

A trip from the Netherlands to Uruguay takes 69 days, at an average speed of 5km/hour.

Some ships might require you to help out with sailing. Other passengers may be required to work look-out shifts. Of course, some passengers may become seasick.

But the site also lists the advantages. You can travel to faraway places without creating a huge carbon footprint. You have time to relax. And out on the open water, you experience the magnitude of the Earth and seas.The Conversation

Christiaan De Beukelaer, Senior Lecturer, University of Melbourne

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