The Calendar Cannot Make It Rain

The territory typically enters its wet season in May. This year, according to a NASA Earth Observatory report carried by ScienceDaily, the expected replenishment gave way to rapidly spreading drought. By August 25, roughly three-quarters of Puerto Rico was experiencing at least moderate drought. Extreme drought covered 44 percent. Three months earlier, none of the territory had been classified as in drought.

That is the strange part: not simply little rain, but the speed with which the season switched jobs. Late winter and early spring had been wetter than normal across the U.S. Caribbean. A July 23 NIDIS update, based on data available July 21, reports that most of Puerto Rico received less than 60 percent of normal precipitation over the preceding 60 days. Southern and southwestern areas received less than 20 percent. The period expected to refill the account was making withdrawals.

Heat sharpened the deficit. By July 21, San Juan was experiencing near-record July heat, and streamflow reached record lows in waterways including the Rio Fajardo. Water rationing has affected several municipalities; farmers face crop losses, and ranchers face dwindling hay supplies. The governor declared an emergency in late July, followed by an August 26 announcement of a USDA drought disaster declaration covering 26 municipalities—13 primary and 13 contiguous.

There is a tempting larger story here: the climate has changed, the old calendar is obsolete, throw it away. That outruns this report. One drought does not establish that Puerto Rico's seasonal pattern has permanently shifted, and the account does not supply an attribution study assigning this event to human-caused warming. A failed season is evidence of a failed season. It need not become evidence of everything to matter.

The calendar argument is a warning, not a diagnosis of this response. The reports document monitoring and emergency action; they do not establish that officials ignored measurements because they expected rain. Historical averages remain useful. What this drought illustrates is their limit: they are not a delivery guarantee.

Consider the difference between waiting for the wet season and waiting for measured recovery. The first can be satisfied by turning a page. The second requires water in soil, rivers, wells and storage. NASA scientist David Mocko describes the Puerto Rico drought assessments as drawing on satellite soil-moisture estimates alongside weather, streamflow and well observations. These measurements capture different parts of the same predicament; they are not interchangeable.

The report also notes infrastructure problems worsening shortages. Drought and loss of household water service are related but not identical events. Detecting scarcity does not itself supply the capacity to move water where it is needed. The sky supplies one constraint; the built system supplies others. This account does not establish which infrastructure intervention would prevent which interruption. It does establish why measuring drought and restoring service are different tasks.

Nor does the island-wide percentage tell us which household can absorb an interruption, or whose service gets restored first. Those are questions for assessing the response, not distributional findings supplied by this report. A better drought map would not, by itself, answer them.

The practical lesson is not to abandon memory. Keep the calendar and read the gauges—but do not mistake either for water delivered. Recovery has to be checked at the household as well as on the map.

May arrived on schedule. The rain owed it nothing.