Trying this spending five (turned into 12) minutes or less per question
q1:
US is o(10k) miles across, probably similar for Europe, China. I have no idea whether Africa or South America have significant train tracks. I know there are only a few transcontinental lines on the US, probably similar for Europe and China, so maybe 100k miles of long range east-west track. north-south is probably a bit less, call it 160k miles of long distance tracks. I live in train-impoverished California, where there are probably fewer train tracks than in other places, no idea whether that’s biased toward long distance or local though. Near here, there’s a train that at least goes to Sacramento, call it about 100 miles of longer-distance train. Then within the bay there’s caltrain and light rail and bart, which creates maybe two circles around the bay, which is like 30 miles n/s and maybe 10 e/w, so a little less than 100 miles around, so my current guess is local trains have about the same amount of track as long distance trains. long distance tracks are probably bi-directional, short range are more likely to be more than that, but not everywhere. Maybe call it 3 tracks per mile. Then 160k miles x (2 tracks of long distance + 3 local tracks) is 800k miles. I don’t like this estimate because it’s very conjunctive but I’ll leave it up anyway.
q2:
The number of planes flying between international hubs commercially is probably not that far off from the number of cargo planes flying internationally, otherwise you could inexpensively increase the number of passenger flights or amount of freight by adding some more of the other to existing flights. Probably that’s not a perfect tradeoff so probably I’ll adjust the freight numbers up after. Major flight hubs probably are in china/japan, west coast us, east coast us, europe. Maybe 2-3 flights per day between any pair of intercontinental hubs. So asia <-> west coast there are maybe 3-5 hubs x 3-5 hubs = 9-25 flights per day, east coast to europe again, and probably I’m missing something so lets double that for ~60 hub pairs x 2-3 flights x 2x that much freight is 300 airplane-fulls of freight. A passenger airplane IME has ~30 rows of ~6-10 seats, probably with the top half of the plane populated, for a volume of 120ft length time 30ft diameter circle is 720 sqft, so 75k cubic feet. Cargo is probably a bit less dense than water, 75k cubic feet is ~3k cubic meters, a milliliter is a cubic millimeter so that’s 3e12 ml3 = 3e9 L and a liter of water weighs 1kg, that’s WAY too much weight so let’s try estimating person weight instead. 300 people *100kg + 50kg baggage = 45000 kg, 45 tons times 300 airplane-fulls is 13k tons/day so 4 million tons/year. I haven’t distinguished at all between 2019 and 2009. Obviously 2019 will be more, probably mostly in and out of China. Since China accounts for ~1/6 of my calculation let’s call it 1⁄6 less in 2009 and 1⁄6 more in 2019, which is completely unjustified reasoning but I’ve gone way over my time limit so 2009: 3.3 million tons, 2019 4.7 million tons.
Trying this spending five (turned into 12) minutes or less per question
q1:
US is o(10k) miles across, probably similar for Europe, China. I have no idea whether Africa or South America have significant train tracks. I know there are only a few transcontinental lines on the US, probably similar for Europe and China, so maybe 100k miles of long range east-west track. north-south is probably a bit less, call it 160k miles of long distance tracks. I live in train-impoverished California, where there are probably fewer train tracks than in other places, no idea whether that’s biased toward long distance or local though. Near here, there’s a train that at least goes to Sacramento, call it about 100 miles of longer-distance train. Then within the bay there’s caltrain and light rail and bart, which creates maybe two circles around the bay, which is like 30 miles n/s and maybe 10 e/w, so a little less than 100 miles around, so my current guess is local trains have about the same amount of track as long distance trains. long distance tracks are probably bi-directional, short range are more likely to be more than that, but not everywhere. Maybe call it 3 tracks per mile. Then 160k miles x (2 tracks of long distance + 3 local tracks) is 800k miles. I don’t like this estimate because it’s very conjunctive but I’ll leave it up anyway.
q2:
The number of planes flying between international hubs commercially is probably not that far off from the number of cargo planes flying internationally, otherwise you could inexpensively increase the number of passenger flights or amount of freight by adding some more of the other to existing flights. Probably that’s not a perfect tradeoff so probably I’ll adjust the freight numbers up after. Major flight hubs probably are in china/japan, west coast us, east coast us, europe. Maybe 2-3 flights per day between any pair of intercontinental hubs. So asia <-> west coast there are maybe 3-5 hubs x 3-5 hubs = 9-25 flights per day, east coast to europe again, and probably I’m missing something so lets double that for ~60 hub pairs x 2-3 flights x 2x that much freight is 300 airplane-fulls of freight. A passenger airplane IME has ~30 rows of ~6-10 seats, probably with the top half of the plane populated, for a volume of 120ft length time 30ft diameter circle is 720 sqft, so 75k cubic feet. Cargo is probably a bit less dense than water, 75k cubic feet is ~3k cubic meters, a milliliter is a cubic millimeter so that’s 3e12 ml3 = 3e9 L and a liter of water weighs 1kg, that’s WAY too much weight so let’s try estimating person weight instead. 300 people *100kg + 50kg baggage = 45000 kg, 45 tons times 300 airplane-fulls is 13k tons/day so 4 million tons/year. I haven’t distinguished at all between 2019 and 2009. Obviously 2019 will be more, probably mostly in and out of China. Since China accounts for ~1/6 of my calculation let’s call it 1⁄6 less in 2009 and 1⁄6 more in 2019, which is completely unjustified reasoning but I’ve gone way over my time limit so 2009: 3.3 million tons, 2019 4.7 million tons.