24

TL;DR The chart is misleading since it compares carbon imprint by mass instead of a measure of how much a human needs to survive. Argument The chart you link contains false comparisons. They are comparing mass of foods against each other. However, you don't eat for mass, you eat for calories (or protein or nutriment, or whatever). A better comparison ...


16

1kg of cheese takes around 10kg of milk to produce (more for some cheeses - e.g. parmesan is around 1:16; less for softer cheeses). So the carbon footprint of cheese is going to be at least that factor higher than that for milk (there will be a little extra from any heat/energy input into the cheesemaking process but this will be small). Sources: http://...


15

I share your frustration with some of the online "carbon footprint" calculators, but if you really care about analyzing the components of your impact, you can still get useful information out of them. First, I think a disclaimer is necessary. Any such calculation is going to have to make quite a few assumptions. Some assumptions may lead to slightly ...


14

I cannot give an answer for your car specifically but I found an interesting study (Spielmann & Althaus 2006) exploring the options of buying a new car or continue on using an older model for Swiss passenger cars. It is concluded that a "prolonged car use [is] the environmentally better option. As a consequence of the continuous use of the car ...


13

Let's assume that the use of fuel is the key factor to contribute to global warming and identify four ways that an individual can choose to cross the Atlantic ocean: Large passenger ships, small passenger ships (sailing boats), large cargo vessels and airplane. Fuel use per transport mode Here are the km a given transport mode delivers per one litre of ...


12

If we diverge slightly from the request for CO_2 per passenger km, and look at energy use per passenger km, then David MacKay's book "Without Hot Air" has a rather good chart. Pulling from that the methods by which one might plausibly cross the atlantic (figures are approximate, as I'm reading them off the vertical scale): A Boeing 747: 52 kWh per 100 ...


12

Unfortunately, knowing what is normal waste generation per capita isn't going to help you much when it comes to being sustainable. To put it simply, the current reality is that it's normal to be unsustainable. That needs to change. There are two things most people can do to heavily reduce waste without too much effort, depending on their situation: ...


11

It's hard to assume how much ecological footprint does one extra passenger add to a freighter. I'd guess it's near zero, since it's a cargo ship which needs some basic facilities for the crew anyway, so one person doesn't mean a difference. The twelve passengers limit for cruisers without a doctor means freighter travel isn't likely to be mass used, but for ...


11

To qualify my answer I have ended up here following research into the new agreement made today in Paris regarding climate change (COP21). There appears to be a consensus that one of the most important ways of mitigating greenhouse gas emissions is to plant trees and then burn them in carbon capture facilities, generating energy but trapping carbon. (I have ...


10

The simplest rule to follow is this: Buy Less Stuff Some people replace large articles of furniture (couch, fridge, bed) every 3-5 years, often for reasons of style or fashion. That stuff has to be made and shipped to where you buy it. If you keep those things for 30 years (which is by no means impossible or even particularly different) you have a big ...


10

Yes, we should leave the larger part of all known fossil fuel reserves in the ground. Scientists have calculated that if we want to keep global temperature rise under 2 degrees C (which was agreed upon in the Paris climate agreement), then we cannot use more than 1/3 of all currently known reserves. ...globally, a third of oil reserves, half of gas ...


9

Well, I'm by no means an expert on giving this answer, and yet I'll take a go at providing something reasonable. Assuming a 1ha biodiverse, properly hydrated, young stage forest with optimal leaf coverage that gives us a solar catchment area of 10,000 square metres. Subtract say 20% to account for immature trees amongst the larger growth, another 20% for ...


9

I already provided an answer to this question here, which was written based on personal experience and knowledge, but in this second answer I wanted to address some interesting details and specific measures I found online. Paper 1 A recent survey paper from the University of Lund says that the best lifestyle choices to reduce your footprint are: 1. ...


9

Original answer (which had a long explanation): I proposed using degree days information to determine a baseload value for consumption of electricity and natural gas by region, and assume anything above this baseload was used for heating and cooling. This assumed that all seasonal changes in energy consumption were for heating and cooling only (so no change ...


9

A related question was asked on SE Skeptics - Is this tealight-flowerpot heater more efficient than just tealights? In the third answer, it is claimed the heat produced by one tea light candle is 0.75 MJ per candle. Where I live, one of the domestic gas suppliers sells gas for 2.78 cents per MJ. The energy value of the gas is 38.713 MJ per cubic metre of ...


8

It doesn't depend on how much you drive, although it may depend on where and how you drive. I would argue that the best use for almost any vehicle is to use it until it is worn out. If it is running when you sell it, the next person is going to drive it, not scrap it. There is a very large 'embodied energy' in a car. Energy used to make the steel, run the ...


7

Here is an answer based on this 2010 Guardian article I found. Not sure how accurate it (still?) is. 4g CO2 for a 'normal' email. 50g CO2 for an email with a long attachment 0.3g CO2 for a spam email (that is filtered out by a spam-filter, or deleted quickly) For comparison; this means that 10 emails a day, 8 without and 2 with long attachment, is on a ...


7

Nothing will beat doing an audit, particularly once you have made progress on the really obvious stuff shown by generic calculators. My wife compiled a spreadsheet of emissions embodied in many activities and products, with a ledger you can fill out as you go. Measure everything you consume or dispose of for a period, then cut back to tracking unusual ...


7

Not a full answer to your question, I do not know the footprint of the servers running the StackExchange sites, but it could be estimated from the information here. Good performance automatically means it uses as little resources (energy included) as possible. You could measure your own carbon footprint while using StackOverflow if you are using an UPS that ...


7

Well, if you are really into it and quite handy, you could turn it into activated charcoal, and then add it to your soil! Grind it into small bits, heat it anaerobically, then introduce high-pressure steam. The result will be charcoal with many fissures and cracks, which is ideal for gardening purposes. Then, before introducing it to your garden, pee on it ...


7

Carbon intensity by shipping method The World Shipping Council provides this chart showing approximate carbon emissions by shipping method: Shipping emissions calculators If that's too approximate, there are a number of different calculators you can try out: The Carbon Fund Business Calculator The last tab calculates annual emissions based on ...


6

I don't know an answer to your question, but I think it depends on how much you drive. I would imagine that a car that is in good shape is best used by someone, who needs a car, but doesn't drive very often and not for very long distances. Like an elderly person, who only uses the car to go shopping at the store 3 miles away, maybe twice a week. If that's ...


6

The guardian article mentioned by THelper to me is suspect. It cites McCaffey that claims that 62 trillion spam messages take 33 billion kWh of power. That's 2000 messages per kWh. Hmm. Let's suppose that the average message is a megabyte. Typical internet connection at the consumer level is aobut 5 Mbit/s So a megabyte takes about 1.3 seconds to send. ...


6

There isn't an easy answer on offsetting time: in theory, the sooner the better, because every year that passes with higher greenhouse gas levels. increases the heat content of the Earth. If you wanted it just to come out net zero addition of greenhouse gases to the atmosphere, over the PV's whole lifetime, then reckon on 20 years if it's monocrystalline. ...


6

It is hard to say because there is such a wide variation in ink formulations. Also, no company is going to tell you what is in their ink, as they will consider that a trade secret. That being said, the only consumable part of a mechanical pencil is made entirely of graphite which is 100% Carbon and Clay. Go with the pencil! Here is a "How it is made" video ...


6

In fact there is an actual increase in energy consumption, though not much. What is done at the end devices is one thing (the encoding-decoding part). This answer from stackoverflow provides a good example: When Google switched Gmail to use HTTPS, no additional resources were required; no network hardware, no new hosts. It only increased CPU load by ...


6

Carbon offsets aren't a perfect solution by any means, but provided the activity being funded by the offset is genuine and sensible for the long term, carbon offsets could certainly be considered to be a good solution. For example, if you help fund technology that reduces fossil fuel use that wouldn't otherwise have been able to be funded, then you could ...


6

The Natural Resources Defense Council commissioned a study in late 2015 to understand the energy consumption from 4K TVs, titled The Big Picture: Ultra High-Definition Televisions Could Add $1 Billion to Viewers' Annual Electric Bills. While this doesn't exactly answer your question as regards the resolution of You-Tube videos, it gives some solid clues. ...


6

CO2 is produced by burning the carbon in the fuel, so if your driving style causes you to use twice as much fuel, you will produce twice as much CO2. Driving aggressively can have a big impact on fuel consumption. It's hard to quantify, but a 50% increase in fuel consumption and CO2 emissions is certainly possible. Conversely, the CO2 emissions will be ...


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