Posted: 1/21/2020 | January 21st, 2020
As people become more conscious of their environmental impact on the world, there’s been an increased focus on air travel — and, over the past year, a corresponding increase in “flight shaming”. The term is coined from the Swedish flygskam, which means “flight shame” i.e. you personally feel shame about flying but, unsurprisingly, it has devolved into shaming others for flying due to its carbon footprint.
After all, there is no denying that flying increases your personal carbon footprint — a lot. My carbon footprint is undoubtedly through the roof because of all my intense flying habits.
But what can we do? And is focusing on this issue really the best use of our efforts? Just exactly how bad is flying really?
Air travel accounts for only 2.5% of global carbon emissions. In the US, flying accounted for 9% of transportation emissions, but only 3% of total carbon emissions. It’s a drop in the bucket when compared to other industries in the United States:
- Transportation: 29%
- Electricity 28%
- Industry 22%
- Commercial/Residential 12%
- Agriculture 9%
So, when looking at the math, flying isn’t really the worst climate offender out there. There are far worse industries out there. Shouldn’t we focus on them?
Cutting down carbon emissions from flying isn’t going to make a big dent in total emissions.
And you can’t just shut off air travel. The world economy relies on it to function. We live in a globalized economy — and benefit from that — because of air travel. Ending all flights would end our modern economy.
Moreover, there are instances where flying is required. I mean, are we going to take boats across the ocean all the time? What if we have to rush to a sick loved one’s side? Driving might take too long.
To me, it seems that we could get bigger wins elsewhere.
But I’m not a scientist. So I called one up to ask about the environmental impact of air travel.
Michael Oppenheimer is a professor at Princeton University, co-founded the Climate Action Network, and has been a leading scientist on climate change for over 30 years. He was one of the principal participants of the Intergovernmental Panel on Climate Change. He said:
If you’re a traveler, you have to worry about four things from aviation. One is just the carbon dioxide emissions…number two, you have to worry about the fact that particulate matter from jets can provide surfaces for the formation of clouds, and that that reflects some sunlight…the third thing would be…the production of tropospheric ozone [a greenhouse gas] through the emission of nitrogen oxides…and then there’s a fourth thing, which is that high-flying jets that actually enter the stratosphere can produce some…ozone, and at some altitudes, they may release particulate matter, which would encourage the destruction of ozone.
My conversation with Prof. Oppenheimer gave me pause. It’s just not our carbon footprint we need to worry about when we fly, which makes the total cost of our flights pretty bad. (But, since the carbon effect is the easiest documented, we’re going to focus on that here.) Further research showed that flying is pretty bad.
Most of the time.
While you can say that, generally speaking, flying is worse than any other mode of transportation, the science is tricky because, since there is a surprising number of variables, there’s really no good apples-to-apples comparison. Depending on the make, model, distance, and the number of passengers in your car, driving might be better — or worse — than flying. The same is true with a bus. How many passengers are on that bus?
According to the International Civil Aviation Organization (ICAO), a round-trip flight from NYC to LA produces 1,249 lbs. (566.4 kg) of carbon per person. A car getting an average of 20 miles per gallon produces 4,969.56 lbs. (2,254.15 kg) for the same trip for one person.1
If you’re driving alone, especially over a long distance, it might better to fly. Yet, on that same trip, if you carpool with three other people, you can get your numbers down by a fourth, making driving the better option.
So it turns out there’s no one-size-fits-all answer. You can’t say “flying is bad, never fly” because sometimes it’s better to fly.
That said, a round-trip flight from Paris to London creates 246 lbs (111.5 kg) of carbon while taking the Eurostar (train) will create about 49 lbs (22.2 kg) of carbon.
From Vienna to Brussels, a flight will create 486 lbs (220.4 kg) while the new night train (which takes around 14 hours) will create 88 lbs (39.9 kg) per person.
The International Council on Clean Transportation also came to the same conclusion when they looked into it. It turns out figuring out what mode of transport is quite complicated. As you can see from their chart, no one transportation option is the best every time:
So what’s a traveler to do? I felt overwhelmed just researching this article and doing the math on all these example trips. I didn’t realize how complex this was. And, as I explain later, depending on the carbon calculate you use, your numbers can be wildly off. So what can you do? Here are some tips I learned in this process to help reduce the carbon footprint of flying:
1. Avoid short-haul flights – A report from NASA showed that about 25% of airplane emissions occur during takeoff and landing, so if you go on a lot of short-haul flights, you tend to have a higher per-pound footprint. So, flying nonstop rather than a bunch of connecting flights is the better option environmentally.
The longer the distance, the more efficient flying becomes (because cruising altitude requires less fuel than any other stage of flying). If you’re flying a short distance, consider driving or taking a train or bus instead.
2. Buy carbon offsets (or don’t actually) – Carbon offsets offer a way to balance out your pollution by investing in projects that reduce emissions of carbon dioxide or other greenhouse gases in the atmosphere. If you used one ton (2,000 pounds) of carbon, you can support a project like planting trees or clean water initiatives that would produce a saving in carbon equal to what you use (so the scale balances).
Websites such as Green-e, Gold Standard, and Cool Effect can give you a list of good projects to support.
But, while these programs help, they aren’t super effective. For example, it takes 15-35 years for trees to grow big enough to capture carbon.
And carbon offsets just shift the burden of what you’re doing to somewhere else. It’s not an actual reduction in carbon emissions; you’re just investing in something that you hope will take as much out as you put in.
In fact, in a 2017 study of offsets commissioned by the European Commission found that 85% of offset projects under the Kyoto Protocol’s Clean Development Mechanism (CDM) had failed to reduce emissions.
Much of my conversation with Prof. Oppenheimer centered on carbon offsets. He said,
Offsets are good if, and only if, they’re accountable, that is, you’re sure they’re producing the greenhouse gas benefit that they’re advertised at, and that’s sometimes hard to figure out because the emissions are not direct, they’re somewhere else…so, you want to only do offsets and count that as part of your greenhouse gas budget if they’re from an accounting system that’s comprehensive and reliable. Secondly, offsets are good if some have been designed to stimulate technological change or other changes that would not have happened so easily without the offset.
He also said that he could “imagine situations where offsets are fine, even beneficial, but there are a lot of situations where they are not and where they’re…far worse than doing the reduction at…the direct emission site.”
I think this is the point. Offsets don’t have strict controls, so you don’t know if they are really working. And it’s far better to force more efficiency from airlines and build up alternatives to flying in the first place. Much of my research showed that offsets, while making you feel good, aren’t as effective as fighting for reductions directly at their source.
So, you can buy them, but be really careful and do your research into the projects you’re supporting.
3. Fight for better flying – We need to put the pressure on airlines to improve fuel efficiency through new aircraft designs and operations, like implementing the usage of biofuels and planes that run on clean electricity, plus modernizing their fleets. For example, the new Dreamliner has very fuel-efficient engines that reduce CO2 emissions by about 20% in comparison to the planes it replaced. Pressure airlines and fly newer, more fuel-efficient planes when you can. Additionally, try to fly an airline that is generally fuel-efficient.
4. Calculate your footprint – As we’ve seen, sometimes it’s better to fly. Sometimes it’s not. Use a carbon calculator for your trip to see which mode of transportation has the lowest carbon footprint for your trip. If flying is a bad option, look for alternatives like trains, ridesharing like BlaBlaCar, or the bus. Some suggested carbon calculators are:
However, I want to put a big caveat here. My team and I used a lot of calculators for this article. We each found a bunch and tested them ourselves to see if our numbers matched. Like peer review scientific papers, we kept checking each other’s work. We were incredibly shocked to find out just how much variation there was between the carbon calculators. My suggestion is to use multiple calculators to find out what your exact footprint is.
Prof. Oppeniemer concurred, saying, “If the calculator shows that the car is worse, I would believe that, because all this is very sensitive to the load factor. And also…since a lot of fuel is burned on takeoff and landing, the longer the flight, you may sort of amortize the trip if you’re in an airplane.”
5. Fly less – At the end of the day, flying less is the best way to reduce your carbon footprint. Taking lots of flights a year, even if you do some of the lifestyle changes we mention below, is still going to cause your personal footprint to be huge. While the above methods will work, the best you can really do is to look for alternatives as much as possible.
I think we should all fly less. I look for ways to fly less all the time. We all need to be more aware of our carbon footprint. But it’s also important to understand, total flight emissions are small compared to other industries. There are so many factors that go into personal carbon footprints that I think we can make a bigger difference through the day-to-day actions we take since, as we’ve seen, most industries have a bigger impact on emissions! Do things like:
- Buy things that last a long time
- Buy secondhand
- Buy local, not online (so much packaging waste)
- Reduce your plastic consumption
- Drive less
- Switch to a hybrid or electric car
- Eat less takeout to avoid the plastic and other waste that comes with it
- Eat less meat or go vegetarian or vegan
- Switch your home heating to renewable energy
- Change your incandescent light bulbs to LEDs
- Install low-flow showerheads and toilets
If you don’t fly a lot generally, the things you do every day can have a huge impact on your carbon footprint and help the environment. Let’s not lose the forest through the trees.
In today’s “cancel culture,” we’re all supposed to be perfect people — but those who cast the most stones are imperfect too.
We all are.
I don’t believe in flight shaming because, when does shaming someone ever work?
When people feel like their values are attacked, they harden their positions. If you shame someone, they will just do more of the same and become entrenched in their positions. Study after study has shown this to be true.
Telling the person they are bad – when no one ever wants to think of themselves as a bad person – won’t get you anywhere.
That’s not how human psychology works.
Instead, I believe in finding and presenting alternatives.
That’s how you affect change.
I’m not going to judge people who fly. Nor will I judge people who have decided the best way to live their values is to fly less.
If you’re worried about the environmental impact of flying, reduce your own footprint, educate your friends on why they should fly less and find alternative transportation, and contribute to some good organizations that are out there fighting for a greener world:
- 1% for the Planet
- 350.org
- Alliance for Climate Education
- Alliance to Save Energy
- Environmental Defense Fund
- Greenpeace USA
- Natural Resources Defense Culture
- Ocean Conservancy
- Oceana
- Pew Charitable Trust
- Union of Concerned Scientists
The world needs immediate action. And there’s a lot you can do to to help. If you want more effective change, donate to NGOs and sociopolitical groups that are pushing climate change action immediately — because the longer we wait, the worse it will get.
Support green-energy projects.
Fund the planting of trees.
Donate to land reclamation.
Fast action will get you more bang for your buck than anything else.
But whatever you do, don’t shame people for flying. That’s not going to do anything.
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1. There are a lot of emissions calculators out there, and many vary wildly. For flights, I went with the ICAO as it’s the most scientific. For car emissions, I used the Environmental Protection Agency (EPA).
Sources:
We did a lot of research for this post. While we linked to some in our articles, here’s some of the other sources we used for this post:
- https://www.yaleclimateconnections.org/2015/09/evolving-climate-math-of-flying-vs-driving/
- https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-typical-passenger-vehicle
- https://calculator.carbonfootprint.com/calculator.aspx?tab=4
- https://www.icao.int/environmental-protection/CarbonOffset/Pages/default.aspx
- https://www.nature.com/news/the-inconvenient-truth-of-carbon-offsets-1.10373
- https://www.bbc.com/news/science-environment-49349566
- https://www.vox.com/the-highlight/2019/7/25/8881364/greta-thunberg-climate-change-flying-airline
- https://www.mic.com/articles/192792/how-to-reduce-your-travel-carbon-footprint-on-your-next-trip
Jane
The other caveat with the whole flight shaming thing is that it originated in Europe where they have a great rail network that many can use as an alternative. We really don’t have that as an alternative in Canada or the US. Our rail systems are antiquated and not highspeed. Cars or flying are our options for the most part. Also our countries are so large that you can’t really compare driving from Ontario to BC and flying the same distance.
Sebrin
Great article to get ppl to A) find resources they need and B) start asking the right questions.
But I think the biggest message I take away from all of this isn’t even about flying and it’s carbon emissions (though I think about it a lot).
At the end of the day, truly believe that we need to be MORE conscious consumers. In everything we do and buy.
Is that a pain? Ya, totally. But we’ve become so reliant on super convenience that I think it’s made us lazy consumers. We don’t know where things come from, what our buying impact does, or where things go. And we’re leaving those details to big business and politicians who ultimately shape our world.
We’ll never be perfect consumers and we’ll always make mistakes. But if we can try to be ever 10% better by educating ourselves on what we buy and what we do (on a sustainable aspect), we’ll all be bette for it.
Sammi
“We don’t need one person doing zero waste perfectly, we need lots of people doing it imperfectly”. I think flight shaming is probably from people who aren’t making chances in their lives to accommodate for carbon.
In my home life we use a renewable energy supplier, our dental floss is compostable, as is my partner’s sanitary products & I use a mooncup, we recycle, we use palm oil free cosmetics…
But we fly a lot. My parents live in the Canary Islands, we visit them twice a year alone. We also went to Poland and Italy by plane last year, and to Bruges by Eurostar. Our return trip on the Eurostar to Bruges cost less than half as much as getting to London.
It was also on radio 2 with regards to train vs plane is that we can travel across the UK on a train BUT 1. It costs £40 return to fly from Bristol in the South West to the Newcastle in the North East and takes an hour. By train it takes 5hrs and costs £368.50! If you were doing that for work it wouldn’t be time or cost effective. I know it’s much cheaper in mainland Europe; there’s even talk of introducing a sleeper train from Malmö to Köln and then you can get connections to the UK by midday or the Netherlands by 9.30. In the UK we’re meant to be getting a fast speed train connecting the south east with the North. However many XR activists are against it (the proposed route cuts through some trees somewhere- I don’t know a great deal about it); which I don’t understand on two factors. Firstly, I thought XR wanted us to use public transport, so why are they protesting it? Secondly why can they not upgrade existing tracks and therefore not cut through a lot of trees? Altho those are probably not questions for here.
Namely my point is the quote at the beginning; we need lots of people trying to cut their carbon emissions imperfectly, not one person doing it perfectly.
Darrell
Skyscanner show the most green flight in their search as well, calculated from a lot of the sites above.
Henry
Great thoughtful article. However, in the list of actions people should take, you completely left out pressure our political leaders to make changes at the top. Many studies have shown that individual actions are not remotely close enough to change our trajectory and while we should definitely be thoughtful of changing our culture of consumption, major businesses and industries are incentivized by the short term gains of profits more than a responsibility to society in general. The most effective way to force them to make changes is through government regulation and the only way to make that happen is for individuals to hold their leaders accountable and put pressure on them. Again, great thoughtful article; I’d just like to see the sole responsibility taken off consumers and shared with government and industry.
Cameron
Citing the ICAO on flight emissions is like asking tobacco companies if nicotine is addictive. Though to be fair, the article provided other resources that contradict the ICAO’s kind assessment of flying’s footprint, just have to dig deeper.
Vaclav Dekanovsky
The whole flygskam campaign is based on a good idea and some (even quite many) people can decide for an alternative over flying at a time. However as you say we will not stop flying. The way forward is to upgrade the technology (in aviation and other industries) to become more environment friendly. Planting a tree at the end of your flight is nice, but unless we manage to shift to greener energy (and I don’t purely mean solar and wind power plants which have benefits and downsides as well) we will not solve the problem. If we as a whole society focus on progress (like in the movie Tomorrowland) we can achieve it. Shaming someone for flying won’t have that power, it might only make us think a bit more about our actions.
Alan L.
Great article to increase consciousness when traveling and in life in general. Realize that while the impacts of flying do not make the largest contribution to planetary pollution, only a very small portion of the worldwide population flies and an even smaller portion are frequent fliers. Busses, trains and carpools, whenever possible, are always more efficient in terms of environmental impacts.
Marc and Julie Bennett
Thank you for all the time and energy spent doing this article. Well researched and helped answer a question I had. Always a pleasure reading your blog Matt. Funny that we often get people trying to shame us for driving our big gas guzzling RV. But they don’t realize that our RV often sits for weeks at a time. We actually spend less on fuel traveling the country than many people do, to drive to and from work every day. And we have a small space to heat and cool, and use far less water than the average household. Ironic that we actually have a much lower carbon footprint than those who accuse us.
George Brown
Flying confidently took painful years in production; too bad it peaked at the moment worries over carbon emissions accumulations peaked. Sorry that’s just too bad.
Chad
Great article! I also think the environmental effect of flying a couple of times per year is fairly low comparative to other things people can do. I tend to caution people from flying often for another reason. I think the real problem with flying is the effect it has on human health.
Most people have no idea about the amount and level of toxins one is exposed to during the flying process. Everything from radiation, de-icing chemicals, flame retardants, exhaust, petrol-chemical fumes and potentially hundreds of random chemical fumes, to bacteria and virus’. Airplanes are routinely sprayed with flame retardants (among other things), which are some of the worst chemicals to be exposed to. In some airplanes the concentration of toxins can be 100+ times higher than in your cars or homes.
There have been court cases coming out in the last couple years because people who work on airlines are getting sick from all kinds illness’. There is all kinds of information available on the toxic cabin air inside of airplanes.
I think that for the average reasonably healthy person, taking an occasional flight will not be the worst thing you can do for your health, but for people who may already be dealing with health issues or for people who are flying often, being exposed to these chemicals could be detrimental to your health. I’m not trying to scare anybody, just raise awareness. Just something you may want to consider.
SM
Oh how I wish their was a train (Shinkansen would be best) to travel form Los Angles to Japan…sadly there isnt…lol….There are just some places in the world one must access and flagon is the most logical way..That being said- I try to travel a few longer trips ,than a lot of shorter ones … and non-stop if available.
Ben
Great article, gives a few interesting insight on environmental impacts of flying. A also agree with the fact that people should be more concerned about what they do daily, in their lives, that could be done better and have broader positive impact in their daily lives.
Though, there was a little something in the article I find important to bring awareness to is the hype towards electric cars. Based on Life Cycle analysis, an electric car becomes better for the environment only when the electricity is created through renewable energies. Anyone reading this and wants to change is car for an electric one must first know how the electricity is produced in its area. The hybrid car (not the plug-in ones) is for now one of the best solution in any country, no matter what they are using to generate electricity.
Just like other comments mentionned it, all consumers should question themselves before buying anything, as everything as a negative impact on the environment, but some have bigger impacts and others have lesser impact. One should always asks himself these three questions before buying anything:
1. Do I really need this?
2. Can I find it secondhand or can I reuse it once I finished using it?
3. Can it be placed in the recycling bin at the end of its life?
This follow a general rule of thumb that is called the 3 R’s (Reduce, Reuse, Recycle).
Have fun in life, but be good to others in the process 😉
Tom
One concern I’d have with the move to new more efficient planes cars etc. (electric/hybrid etc.) Is the emissions from production. Often it would take years and years for the carbon savings due to efficiency to pay back the initial debt from manufacture.
It’s a balancing act of getting the most out of each vehicle to diminish production emissions/distance travelled, Vs actual running efficiency.
Nathan Smith
Great topic. I completely agree with the thesis here. Thanks for spending time on your research and acknowledging the complexity of it all. It is never black or white.
Ian Williams
Very useful article. Air travel make cause a small portion of carbon emissions but it’s also only serving a small proportion of people on the planet. Apparently only 5% of the world’s population have EVER flown!
Kate
Thanks for a well-balanced article. So rare in today’s world. I agree with Jane about the difference between Europe, with shorter distances and more rail options, and North America with the opposite. And thanks, Sammi, for “We don’t need one person doing zero waste perfectly, we need lots of people doing it imperfectly”.
This article and discussion has prompted me to change my usual summer plans, and to fly east, then commit to buses and trains.
(PS Good to see you at the Austin get together.)
Denise & Ryne
Great article! The best things everyone can do right now is to reduce meat consumption and buy as little plastic as possible. But just like you said, you can’t make other people feel bad or shame them for how they’re living.
How do you guys reduce your carbon footprint? 🙂
Ali
Unfortunately, the government did not take enough care in the past years. They went for the easy solution and didn’t invest in more sustainable transportation like fast trains.
We should ask them to take action on that, we can do that with being active in our local and national politics.
And of course, these are side work for all you and others mentioned.
Kathy
We live in New Zealand. Our unique problem is lack of any other countries under 2000km away. Our economy depends on tourism and our lifestyle encourages young people to get “overseas experience” to bring back into our economy. We also love to travel and most New Zealanders do travel, often to Australia. Most of us are also immigrants with families all over the world. I have travelled extensively and still want to do so at least once a year. But even I am feeling irresponsible for doing so. We are doing a trip in three weeks which may well be our last long-distance one. I can’t let other countries suffer the results of my desire to enjoy myself.
However in our defence- most New Zealanders go overseas for a long time. When you go you go for a few years or months because it is so costly compared to our low wage economy. When we get to another continent we happily use trains because we are so amazed how fast, comfortable and efficient they are. They are also very cheap in some places. I personally enjoy looking out the window and seeing daily life. Because of the cost we tend to space our trips out and more often go to countries closeby (relatively). We are also trying to plant a billion trees to do our bit. We don’t need to make many changes to our daily life because we’ve always been pretty green about most things. Our power production is also pretty reasonable being mostly based on water, hydrothermal power and wind.
Despite this, I still feel we need to start thinking hard about the choices we are making when we travel.
Dorene Wharton
Great post, and thorough research – and I agree its confusing and complicated. I’d like to add that biofuels are hitting the market now, although they can only help short haul flights (Jet blue just announced their move to them). Hopefully this becomes widespread- and we can vote for them in who we buy flights from. The one area I’ve seen at the top of the list is refrigeration/AC/heating – as the #1 biggest opportunity and today we don’t have a good solution to manage it, although NYC is imposing regulation and financing for 1million buildings to update their energy. Let’s hope this too becomes wide spread. Also lets vote for companies that are investing not just in carbon reduction but carbon capture – because we all know the speed and pace the world is changing isn’t enough.
KC
I know this was not the focus of the article but it’s important to remember that flying commercial aviation (on a mile to mile basis) is safer than driving. The human costs of injury and death in promoting driving over flying should play into any calculation.
Richard
Nice work. I try to stay in one country for three months now to cut down on not only emissions, but cost too.
Agreed that it doesn’t do any good to shame others or feel guilty about flying. We can just try to do better.
Viajes Elan
Hello,
Thanks for the information, one of the things we do in all our trips, staycations or excursions, to cushion the impact of our visit is to collect the garbage that others have left and clean the destination visited. You’d be surprised at how much can be collected.
Thanks for sharing.
Hannah
Thank you for sharing all of your research with the world! I also appreciate the additional comments and recommendations to pick up trash, volunteer, etc.
I too share your passion for travel — and saving the world, which seems to be a contradiction given the pollution of travel.
I will share, that while I already do all of the shared tips for cutting carbon footprint above and abroad, I also do think “flight shaming” has been beneficial in some ways.
With the advent of millions of travel IG accounts, it seems like everyone is a professional traveler these days. And if you aren’t a professional, the travel inspo has certainly made international jet setting seemingly more popular.
So though I don’t think we should be shamed for traveling, I do appreciate that “flight shaming” might give someone p a u s e to consider the repercussions of clicking purchase of that flight.
Like mentioned in an above comment, “we need everyone imperfectly trying to reduce their footprint just a little”.
If we all bought 1 less flight a year, wouldn’t that eventually lead to an airline flying the route for example from Mexico City to NYC one less time per day? One less flight flown on each route will eventually decrease the emissions by plane flights dramatically.
After all we do vote by our pocketbook. Airlines will eventually listen and fly less flights and use more Dreamliners with cleaner emissions based on demand.
So yes, Shaming someone is never right. Showing them to be conscientious of their decisions is.
Jamie
A well researched and written article. Agree with much of it. I think we need to be careful with that stat that 2.5% of carbon emissions are from flights. It is true, but after we factor in the things Prof Oppenheimer mentioned to Matt, i.e. flights causing global warming from things other than CO2, it is more like 5% of climate change and growing. Source: https://www.sailtothecop.com/blog/aviation-more-than-10-of-emissions However, the reason flights are only 5% is because most people don´t fly, or only short haul. If you take one long haul flights per year, it will typically be 20%-50% of your emissions. Reducing those flights will perhaps be the most important thing you can do to reduce your emissions.
The average person on Earth today has a carbon footprint of about 7 tonnes of CO2e. To avoid catastrophic climate change, i.e. to have a reasonable chance of not going beyond 2C above pre-industrial levels, those numbers need to be down to perhaps 4-5t CO2e without 10 years and perhaps 2-3t CO2e within 20 years.
Most return long haul flights are between 1t and 4t CO2e. When we allow for the fact that each person inevitably has some other emissions as well as their flights, it is therefore basic maths that in years when I took long haul flights, I was not living a life consistent with 2C, and was taking more than my fair share of the world´s carbon budget regardless of what else I did to cut my carbon footprint. We can´t be allowed to let fear or shaming stop us from confronting cold hard facts.