An international team of scientists has concluded that the recent drought in the Panama Canal was not caused by global warming but by lower-than-normal rainfall associated with the natural climate cycle El Niño.
Low reservoir levels slowed freight traffic on the canal for much of last year. Officials had to cut the number of ships allowed through last summer because there wasn’t enough water to lift and lower the ships, creating a costly headache for shipping companies around the world. It was only in recent months that crossings began to pick up again.
Researchers say the region’s water problems are still likely to deepen in the coming decades Their analysis of drought. Water demand is projected to increase significantly as a proportion of available supply by 2050 as Panama’s population grows and seaborne trade expands. government. This means that future El Niños could bring wider disruption, not only to global shipping but also to water supplies for local residents.
“Even small changes in precipitation can have disproportionate impacts,” said Maja Vahlberg, a risk adviser at the Red Cross and Red Crescent Climate Center who contributed to the new analysis released on Wednesday. Made a contribution.
Overall, Panama is one of the wettest places on Earth. On average, the area surrounding the canal receives more than eight feet of rain per year, almost all during the rainy season from May to December. The rains are critical for canal operations and drinking water for about half of the country’s 4.5 million people.
However, last year’s rainfall was about a quarter below normal, making it the country’s third driest year in nearly a century and a half. Soon after, two more droughts struck that also hampered canal traffic: one in 1997-98 and another in 2015-16. All three phenomena occur simultaneously with El Niño.
“We’ve never had so many really intense events in such a short period of time,” said Steven Payton, director of the Physical Monitoring Program at the Smithsonian Tropical Research Institute in Panama. He and other scientists who conducted the new analysis wondered: Was it just bad luck? Or is it related to global warming and therefore a harbinger of things to come?
To answer this question, the researchers looked at Panama’s weather records and computer models that simulated global climate under different conditions.
Scientists have found that the main reason for low water levels in canal reservoirs is low rainfall, rather than high temperatures that cause more water to evaporate. Weather records show that Panama has experienced slightly less rainy season rainfall in recent decades. But these models do not show that human-induced climate change is the driver.
Clair Barnes, a climate researcher at Imperial College London who was involved in the analysis, said: “We’re not sure what’s causing this slight drying trend, or if there’s an anomaly or something else that we haven’t accounted for. factors.” “Future trends in climate warming are also uncertain.”
In contrast, scientists found that El Niño is more strongly associated with below-average rainfall in the region. They estimate that in any El Niño year, there is a 5% chance that rainfall there will fall to 2023 levels.
According to the National Oceanic and Atmospheric Administration, El Niño is currently weakening. La Niña is the opposite phase of the cycle and is expected to occur this summer.
The scientists who analyzed the Panama Canal drought are part of the World Weather Attribution Project, a research initiative designed to examine extreme weather events immediately after they occur. Their findings about the drought have not yet been peer-reviewed.
