Panama Canal Under Threat From Global Warming

In Panama, man-made mastery and misery have collided. For a hundred years, its world-renowned canal has achieved the once-unimaginable – linking the planet’s largest oceans. But this marvel of engineering is succumbing to another work of mankind: climate change. Earlier this year, authorities ordered cargo ships to lighten their loads, lest they scrape the artificial waterway’s bed. An unseasonably severe drought – driven by global warming – had seen the canal’s surface drop five feet lower than expected, risking the hulls of the biggest boats. Conditions have now normalised, but experts warn that the worst is still to come.    

A wholly artificial body of water, Lake Gatun, forms two-fifths of the interoceanic canal. Joined by a smattering of ferries and cruise ships, some 3% of world trade passes through the stretch every year. To accommodate the traffic, the lake fills during the wet season – April to December, typically – and whittles down the excess when temperatures rise. As the year draws to a close and the rainfall eases, water levels should be around 26.5m – in the early months of 2019, they scarcely topped 24m.      

The most intense drought in Panama’s 116-year history was to blame. Persisting through July, it immediately followed a particularly torrential wet season. This twist in meteorological fate – or, perhaps, evidence of an increasingly erratic climate – softened the blow of the drought, but still the pain was felt. Five successive cargo weight reductions were ordered as water levels plummeted. The biggest ‘neo-Panamax’ ships were hit the hardest – their titan hulls, introduced after the canal 2016’s expansion, sit lowest in the lake. Had the surface dropped just centimetres more, the second tier – ‘Panamax’ ships – would’ve been at risk too.

More numerous than their larger kin, this would have cost canal authorities dearly. In reality, they enjoyed a narrow economic escape – the restrictions cost an estimated $15m, a speck on the waterway’s $2.5bn annual revenue. Still, there is reason for concern. With Panama City’s rising population and increased canal traffic, the strain on water levels is only set to increase.  

And then there is climate change. As global temperatures rise evaporation quickens, depleting water reserves ever faster. In Panama, several severe droughts since 2015 suggest that dry seasons are becoming longer. They may also be starting earlier (this year the rain tailed off a month before normal) and ending later. Storms are becoming more severe too – four of the worst to hit the region have occurred in the past decade – with rainfall more torrential, but overall diminishing in volume.  

Sceptics point to the ‘El Niño’ phenomenon. This natural occurrence sees warm water move eastwards across the equatorial Pacific Ocean, bringing with it stronger, more erratic storm systems. It’s a cyclical process, alternating sometimes only once in a generation, blurring the line between man-made and organic weather. But there is compelling evidence that, even if not immediately caused by climate change, El Niños are intensifying as the planet heats, linking global warming to Panama’s problems indirectly. 

It’s a point not lost on those in charge. “We have invested vast resources and time over the last decade to ensure our operations are cleaner and produce less emissions so we can minimize our impact on global warming,” said Jorge L. Quijano, the waterway’s chief administrator.   

He’s got good reason to be green-minded – water is Panama’s lifeblood. Accounting for an eighth of national revenue and providing 9,000 jobs, the canal’s financial fortunes ripple far and wide. When profit is lost to the unloading of cargo (shipping firms pay per weight of their haul), it hurts everyone. That’s especially true at present with the US/China trade war slashing the canal’s typically high Asian traffic, which accounted for 35% of business in 2018.

But water’s importance to Panamanians goes far beyond the economic. A full 95% of drinking water is derived from rainfall, which also powers the nation’s hydroelectric infrastructure. It irrigates fields too, and, far from the cities, sustains small indigenous communities. Scores of native villages straddle Lake Gatun’s tributaries, and depend on boat-borne tourism for income.           

Their fate hangs in the balance, experts say. “As for the future, it is difficult to forecast,” said Steve Paton, a climate analyst at the Smithsonian Tropical Research Institute.

We are observing in the canal area that climatic events are becoming increasingly extreme

Aware of the crisis ahead of them, the waterway’s administrators are scrabbling for solutions. In the short term, they can implement outflow recycling measures and pause hydroelectric production to save water. But these are temporary fixes. A third artificial lake may have to be dug to store excess rainfall for use during prolonged dry spells. But this would require huge tunnelling efforts and the construction of new dams, both of which come with grave ecological warnings – and perhaps even the displacement of natives. 

But if the canal is to remain economically viable, it must continue to expand. Otherwise, it may fall victim to the growth of new, more predictable interoceanic routes, like rail lines across the United States. And global warming could have another cruel twist in store for Panama – the opening up of previously ice-clogged passages through the Arctic, which would cut the East-West journey by thousands of miles.   

It would be a sad eventuality, given the canal’s strong environmental standing. Since its opening, the passage has helped save an estimated 750m tons of CO2 by offering ships a less circuitous route. But the steady advance of global warming shows no sign of slowing, and experts fear the worst. In just a decade-and-a-half, the canal’s water level could drop irreparably low. One of man’s greatest creations, undone by one of its worst.