Who will drink the last glass of water in Cape Town?

Because Cape Town sits between picturesque beaches and mountains, it is a favored travel destination. And, its weather during the summer is described as "almost too perfect." That's in part because it rains very little in the summer in this second most populous city in South Africa.

Water, water everywhere, but not a drop to drink

Trouble is, starting in 2015 the rainy season never arrived. One year, then two years and now three years of extreme drought have brought the city's water supplies almost to exhaustion. Barring extraordinary rains or even more draconian cutbacks in water usage than have already occurred, Cape Town officials say they will have to turn off water to most household taps and businesses sometime in April. They're calling it "Day Zero." Hospitals and essential public facilities will be exempt. Most residents would have to line up at designated water supply stations for a daily allocation of 25 liters.

The energy of Bitcoin, the information economy and the (possible) decentralization of the world

The near vertical rise and fall in price of the cryptocurrency Bitcoin in recent months has been accompanied by reporting about the energy used to run the Bitcoin network. The amount is enormous, more than enough to supply the entire country of Ireland.

Many other cryptocurrencies operate under less energy-intensive designs. But the more than 1,000 other digital coins beyond Bitcoin certainly use a considerable amount of energy though there is no overall estimate I'm aware of. (For the technically minded, here is a discussion of two popular methods associated with validating transactions, one of which is considerably less energy-intensive.)

We'd like to think that the information economy of which these newfangled currencies are part bears lightly on the broader environment. But as I pointed out in my piece "The Unbearable Lightness of Information," much of what happens in the information economy is simply focused on extracting more resources more quickly to create more goods and services for more customers. The physical economy isn't disappearing. It is merely being exploited more completely using digital information.

Protagoras and the Anthropocene: Can man still be the measure of all things?

The ancient Greek philosopher Protagoras is famous for his saying that man is the measure of all things. Though we don't know much about Protagoras or his written work except for quotations appearing in other ancient works, the general view is that Protagoras was the father of moral relativism in philosophy.

Protagoras's complete statement has been translated as follows: "Of all things the measure is man, of the things that are, that [or "how"] they are, and of things that are not, that [or "how"] they are not." It is unlikely that Protagoras believed that physical truths about the natural world such as the freezing point of water depended on one's personal standpoint.

But under Protagoras's tutelage in matters of values, we are left only with the measuring instrument called "man" (or more inclusively "humans"). In the age of the Anthropocene—that still-not-official geologic age in which humans are designated as the most potent geologic force on the planet—those issues thought to relate solely to the lives of humans do NOT, it turns out, relate simply to humans.

Hawaii's existential choice: Tourism, food and survival

Hawaiians used to feed themselves quite easily on this island paradise. With the arrival of Europeans and Americans came European and American ideas about plantation agriculture. Hawaii became a producer of coffee, sugar, pineapple, papaya, rice and other plantation crops.

While destroying Hawaii's diverse food system, the growers created a prosperous agricultural trading economy with mainland markets as customers. But competition from low-cost producers elsewhere has more recently devastated that economy. The last remaining sugar plantation closed in 2016.

The decline of the previously large sugar and pineapple industries now make Hawaii much more dependent on tourism as a source of income. Tourists are Hawaii's largest industry. They spent $15.6 billion in 2016 on vacations there representing about 18.5 percent of the total economy. That certainly underestimates their importance as many additional support services are needed to maintain the businesses that service the tourists.