Do you wonder what all the fuss is about global warming and carbon footprint reduction?

Then this blog can help you.

Current human activity emits around 50 Gt of greenhouse gases (carbon dioxide, methane, nitrous oxide, etc., measured in terms of their equivalence to carbon dioxide) into the atmosphere per year. That's on average 6 tonnes per person per year. Three-quarters of that is due to carbon dioxide.

That doesn't include water vapour (mostly steam from natural and industrial processes and clouds). Water vapour makes the largest contribution of all to global heating. Before industrialisation it was just keeping us comfortably warm. Now we've also added to it, but it's a relatively minor proportion of the overall water cycle so far. Water vapour luckily cycles through the atmosphere as our weather, about every 10 days.

The other greenhouse gases unfortunately hang around in the atmosphere for decades or more, and hold in the heat too. This amplifies the effect of water vapour, because warmer air holds more vapour.

A warmer atmosphere puts more energy into the weather systems, giving more severe rainfall (causing floods) and drought (causing fires), and more damaging storms. Increased temperature at high altitude and high latitude melts more snow and ice, raising sea levels (drowning coastal sites), depleting glacial water sources (used to irrigate crops in summer), and lowering the earth's ability to reflect sunlight, raising the atmosphere's temperature further.

Increased global temperature means the climate bands move away from the equator, making it harder to grow food at low latitudes, causing political discontent due to food shortages, and driving migration. At high latitudes very cold climates become more mild, but the loss of permafrost releases more carbon dioxide and methane, accentuating the problem, and destroys connecting infrastructure which has to be rebuilt using environmentally damaging concrete.

To avoid an average global temperature rise of more than 1.5°C over pre-industrial levels (we are currently at 1.2°C) our emission rate needs to be cut by 50% by 2030, to about 3t/person/year.

We need to go further after that, to around 1t/person/year by 2050, due to the delayed consequences of our past activities, to get proper control. It's clear that if we don't make good progress reaching the above goal by 2030, it will be too late, so let's focus on that.

What are the prospects of achieving the 2030 goal?

An investigation with a carbon footprint calculator quickly shows that living in a developed European country, even being circumspect (i.e. eating low/no meat, flying little, using public transport when possible, etc.) you are likely to be several times over the 2030 target. Your footprint will likely be split relatively evenly between food, travel, household and the rest ("societal").

Transport is key, and the role of the private car is questionable. It is too late to remove the footprint of your existing car, but whether to replace it, and with what, are the key questions. If you live in a city, a car is a luxury, so consider doing without it. If you live in the country it's less of a luxury, but buy a bicycle trailer and use it when you can. In both cases as you get older you'll have to rely increasingly on deliveries, which are somewhat more environmentally efficient than your own car. Certainly minimise your car use to just essential journeys and if you must, on renewal, buy an electric vehicle, although whether the full life-cycle footprint of that is low carbon (or environmentally sustainable) is still in question. Of course, use public transport whenever you can, especially where it is powered by renewable electricity, as soon as the pandemic is over.

Air travel is a real luxury. A 2000 km round trip adds 0.4t of greenhouse gases (13% of your "allowance") to your personal footprint. Although long haul flights are perhaps 25% more efficient per km, you have to consider avoiding air travel just for pleasure.

Your biggest household running contributions will be heating and electricity. Oil heating is the most energy efficient, but is the worst greenhouse gas contributor. The overall effect on the climate of possible alternative bio-fuels and -gases are questionable. No alternative is perfect, but a modern wood-chip-powered furnace apparently has a low footprint. Again, the particulates released, and the fuel security, are a concern. Especially as there are benefits to planting trees long term (letting them grow for at least 60 years), so having to farm them for fuel is not helpful. Air heat pumps are also rated as good, but have a reputation for the nagging noise of the fan. If you have a sunny roof, solar thermal or photovoltaic could already contribute somewhat too. Another idea is to directly generate hydrogen from sunlight, using it in a fuel cell for electrical heating. But the technology is probably at least a decade or so away from a safe, acceptably priced reliable domestic cycle. There's really not much to choose from to have an impact by 2030.

For electricity consumption, if you choose the right tariff, and pay the premium, you can push your supplier to maximise their renewable generation portfolio. Even nuclear can help, despite its well-known issues. You can also choose efficient appliances and insulate your house more, and use water efficiently, making better use of the energy and investment in the considerable facilities needed to clean and recycle it.

Beyond that are the remaining societal effects:

• your house;
• its equipment and contents;
• travel, electricity and communication distribution infrastructure;
• municipal buildings, administration and government, local and national;
• the contribution from industry and its transport you use by your consumption of security, goods and services.

Those responsible for those systems are pledging to lower their carbon footprint over the decade, but you can and need to help too by reducing your demand.

Given all the above, you will see that there is some scope for reducing your individual footprint, but to 3t/person/year? This seems a tall order. But, surely, not everyone in the world is living like a European. Can't you rely on those in warmer but less-developed countries to compensate?

At the moment the average European is not too far from the world average. In 2016 their average footprint was about 8t/person/year. USA citizens averaged 2.5 times that, and Russian Federation citizens nearly twice. We need them to both work hard to bring these down significantly. Already today, the average Chinese citizen has an individual footprint comparable to a European, with more than 2.5 times the population. This not only is due to the higher average standard of living in China nowadays, but also to China's increasingly dominant role in the global economy, particularly in environmentally heavy products developed countries avoid producing. That lowers developed countries' apparent footprint, yet these orders increase China's - China does developed countries' dirty work and in a way that may not be acceptable "back home".

Luckily Indian citizens average one quarter of a Chinese/Europe citizen's footprint, with a similar population to China, helping to lower the world average, and the total footprint. The average for the rest of the world is comparable to the world average, so there is not much hope that poorer countries ways of life will rescue the carbon footprints of the richer abusers. Rather the contrary. Without existing Indian and some other countries' frugality things would already now be much worse. We all have to learn to live a bit more like them.

Lowering our footprint as much as needed has significant implications on the way we go on, which we somehow have to swallow. Now the pandemic is beginning to retreat, we cannot just go back and carry on in our old ways. Our consumption in future has to follow what we need, not what we want. We are not all toddlers, so we need to act more grown up. And the products we do buy have to be more recyclable, and upgradeable if there is an emission benefit. This will cause some changes in industry and the skills required. The employment market will change its emphasis, but not necessarily its bulk. It won't just be a question of developing and marketing new products, but of manufacturers and consumers having incentives and penalties that ensure efficient resource use with minimal climate damage. We need to include the complete life cycle.

The travel industry needs to adapt with us. The prospect of hydrogen-burning aircraft polluting the upper atmosphere with more water vapour doesn't seem to be the right way to go, even if it were technically feasible. And hydrogen-fuel-cell-powered electric engines are a long way from viability, if viable at all for aircraft. So travel will, at least for the next decade, have to become more land-based, more local, and more leisurely. This will mean regrowth in some travel regions, and reductions in others, and will affect the economy of those idyllic but isolated places that rely mainly on tourism the hardest.

Agriculture and the food production system also need to adjust. We already know we have to move away from a diet dominated by meat to one that is largely vegetarian or vegan. Meat production is just too inefficient as a food source. Once the methane from animal husbandry is reduced, the human contribution will also come under pressure to be reduced too, with more careful and lower methane-producing diets being advocated, and in general food waste being minimised and handled better. This need not be feared. Such diets are often healthier than those involving animal products, and can nevertheless be both delicious and nutritious.

So can we make the target in time? As a society there is much to do, but there is also a lot of scope for improvement. Businesses were already moving towards reducing their footprint for economic competitiveness, even pre-pandemic. We need Governments to help now both by legislating for projects that are good for reducing greenhouse gases (like household insulation) and not those that are not (like airport extensions). They have to set a good example on this to everyone, and not pretend we won't have to make sacrifices, or that new and unproven technologies will save us. Certainly not on the 2030 timescale, if ever.

They also need to look to making their own administration work more efficiently, and increasingly digitally and online, at the same time as a necessary consequence making a good enough internet connection and access to it feasible for all citizens, whatever their income. The pandemic has helped us a bit there already but there are still many who cannot afford this now essential and footprint-lowering service.

By our electoral choices, we have to hold our governments to account to do their part. But it is mainly up to us. We can have a large influence by our own lifestyle, which has to change drastically. Are we up for it? The pandemic has given us the chance to examine our life choices, and we have a clear chance now not to fall back into our old ways. One thing has definitely become clearer. Our planet can no longer take whatever we throw at it without flinching. We are now so numerous and developed that we seriously affect how well our planet supports us. We should also be clever enough now not to break it.

You may be wondering why Governments and entrepreneurs are so interested in establishing the infrastructure for bases on the Moon and Mars. Although currently outrageously expensive, such bases could in due course provide a lifeline for our civilisation if we don't come to grips with the climate crisis. It won't be easy to continue, but it will be possible and may get easier. But it will not help those of us left behind here on earth. It is up to us now to ensure we will have somewhere decent to live in future.

1. Cut consumption to needs not wants.
2. Recycle and reuse.
3. Don't travel by air for pleasure.
4. Avoid having a private car - if necessary replace with electric when due and travel less.
5. Use public transport.
6. Eat much less meat and dairy, and prefer local produce.
7. Insulate, turn down heating, and use a low net carbon heat source.
8. Insist on renewable electricity.
9. Be ready to change previous habits.
10. Don't rely on unproven technologies.

This blog was written by Bill Spears, proprieter of the Syoph organisation.

If you have corrections, questions, suggestions or other comments please address them to him. You will find his contact details in the site notice on the login page of Syoph.