The New York Times yesterday ran an adorable puff piece on its website showing the San Diego Zoo’s polar bears enjoying their early Christmas present: an enclosure full of artificial snow. Thanks to a donor, the bears received nearly 26 tons of the fine powder, in which they happily played and frolicked.
While even someone as hardened as I exclaimed, “Aww,” nevertheless something irked me about it: how can the San Diego Zoo justify producing 26 tons of artificial snow at a time when the State of California is experiencing a drought?
This is a drought so severe that restaurants are no longer permitted to serve water unless specifically requested by a customer. And in the zoo’s home town of San Diego, water rates will increase by 16% next year.
To give an idea of scale, 26 tons of snow works out to about 830 gallons of water, or about the amount of water an average American uses in 8-10 days. All for the polar bears to play in snow.
On top of the water involved, there is also the energy needed to produce just under 26 tons of snow. Although the amount of energy used for artificial snowmaking can vary dramatically, one study I found concluded on average it is roughly 3.5-4.3 kilowatt hours per cubic meter of snow. And these were studies at ski resorts with cold temperatures, so I suspect the energy expended might be even higher for San Diego.
A cubic meter of snow weighs about 50kg, so if we do the math (and if I did the math correctly), then the amount of energy expended to produce 26 tons of snow would be about 1,600-2,000kwh. For those of you who don’t think in kilowatt hours, that’s about enough energy to run 2-3 modern refrigerators for a year.
In terms of carbon emissions, the carbon intensity of California’s energy market is 51.4 kilograms of carbon dioxide per million Btu (fascinating, no?). That makes for roughly 300-350kg of carbon dioxide emitted to produce the polar bear’s fleeting winter wonderland. (Unless, of course, I screwed up the math.)
Given the amount of water and energy involved, is it truly conscionable to give polar bears the gift of snow?
The San Diego Zoo did not respond to a request for comment.