Plan B Forum

Lake Tea

What if we were to dump all the tea in the world into the Great Lakes? How strong, compared to a regular cup of tea, would the lake tea be?

Alex Burman

Weak, bordering on homeopathic.

The standard cup of tea, as described by the International Organization for Standardization in ISO 3103, contains two grams of tea per 100 mL of water.[1] The Great Lakes have a volume of about 22,600 cubic kilometers, which means we would need about 450 billion tons of tea to reach proper strength.

According to the Tea Board of India, one year's global tea harvest totals only about 4.8 million tons,[2] only 1/100,000th of what we'd require to make Great Lake Tea. If we dumped those 4.8 million tons into the lakes, the resulting tea would be about as strong as if we'd dripped two drops of tea in a bathtub.[3] Proper bathtub tea, of course, requires one 3-kg bag.
[Cue strong opinions about adding sugar to bathtubs.]

For better lake tea, we should find a lake with a volume of 240 million cubic meters (0.24 cubic kilometers).

Wular Lake in Kashmir is one candidate. Its volume varies with the seasons, but during the winter it's just about exactly the right size.[4] India is the world's second-largest tea producer, so it's also conveniently located.

Ullswater, in the UK's Lake District, is another great candidate. With a relatively stable year-round volume of about 0.23 cubic kilometers, it would be an excellent site for brewing a global cup of tea.

Of course, while neither Wular Lake or Ullswater has ever been used as a giant teakettle, something like this was—famously—attempted in my own backyard in Boston. In 1773, a group of colonists disguised as American Indians[5] boarded three British ships and threw the cargo of tea—around 44 tons of it—into Boston Harbor to protest British-run tax policy.

Boston Harbor has a volume of about 0.44 cubic kilometers, which means that the "tea" brewed in 1773 would have been even more dilute than our Great Lakes tea. The harbor is also somewhat larger[6] than Wular Lake or Ullswater, so all the tea in the world would still make Boston Harbor slightly too weak.
[Although it's a lot better since we built that treatment plant and stopped dumping all our raw sewage in.]

There's another problem: Heat. If you wanted to make tea from a lake, such as Ullswater or Wular Lake, you'd have to heat the water up. Is that even possible?

There's clearly enough stored energy in the world to do it. After all, we presumably heat that amount of water for tea every year already; we just do it in small batches around the world.

To heat up Ullswater to 80°C[7] would take 6.6×1016 joules of energy—about 20 days worth of British electricity consumption. which is roughly what would be released if you dropped a water bottle full of antimatter in the lake.
[Not a significant source of riboflavin.]

Asking Britain to go without electricity for 20 days just to fill one of their lakes with tea seems like it might be a hard sell. Fortunately, there's an easier solution.

Boiling Lake in Dominica is a volcanic lake about 60 meters across. Its temperature varies, but it's often near boiling at the edges and vigorously boiling in the center. Measuring the depth of the lake is difficult, so it's hard to get an estimate of the total volume.
[The fact that it seems to boil away sometimes doesn't help.]

Frying Pan Lake in New Zealand, on the other hand, is the largest hot lake in the world. It has a volume of about 200,000 m3, and an average temperature of around 50°C—not quite hot enough for tea, but much closer than Ullswater or Wular Lake.

New Zealanders consume about 600 grams of tea per person,[8] for a total of 2,700 tons of tea. If they waited until Frying Pan Lake got particularly hot, then dunked it all in at once ...
[We are making a good decision by doing this thing we read on a blog. We are going to have so much tea.]

... they could brew a year's worth of tea in minutes.

http://what-if.xkcd.com/79/