The failure of a vital ocean upwelling has sparked concerns of catastrophic effects for life, according to scientists.
Every year, between December and April, northerly winds create a rising current in the deep waters of the Gulf of Panama.
This upwelling brings cold, nutrient-rich waters to the surface, protecting vulnerable coral reefs and triggering an explosion of ocean life.
However, researchers now say the Panama Pacific upwelling has failed for the first time in over 40 years of records –Â and it could be a permanent change.Â
The researchers warn that the collapse of this critical yearly pattern could have ‘potentially massive’ consequences –Â and climate could be to blame.
Dr Aaron O’Dea, of the Smithsonian Tropical Research Institute, told Daily Mail: ‘Over 95 per cent of Panama’s marine biomass comes from the Pacific side thanks to upwelling.
‘It’s the foundation of our most valuable marine export industry – nearly $200 million annually.
‘Without upwelling, we’ll likely see collapsed food webs, fisheries declines, and increased thermal stress on coral reefs that depend on this cooling.’
Scientists say that a vital ocean upwelling that normally provides food for 95 per cent of Panama’s marine life has failed for the first time on record
Peaking between January and April, the Panama Pacific upwelling is an absolutely key part of Central America’s ocean ecosystems.
Historically, this ocean current has started as early as January 20 and lasted around 66 days.
As the current circulates, it brings cold water from deep below to the surface and causes temperatures to dramatically fall.
During the upwelling, sea surface temperatures dip to lows of 19°C (66.2°F), with lows reaching as cold as 14.9°C (58.8°F).
However, this year, sea temperatures didn’t drop below 25°C (77°F) until March 4, 42 days later than usual.
This cool period was 82 per cent shorter than normal, lasting just 12 days, and only reached lows of 23.3°C (73.9°F).
That is a sure sign that the current bringing cold water to the surface has failed for the first time.
Dr O’Dea says: ‘This system has been as predictable as clockwork for at least 40 years of records – and likely much longer.
In a normal year like 2024 (pictured) the upwelling of nutrient-rich water causes a bloom of ocean life seen as an increased
However, this year (pictured), the upwelling and the bloom of life have failed to materialise leading to low levels of chlorophyll in the waterÂ
What is an ocean upwelling and why is it so important?
An ocean upwelling is a process where deep, cold water is pulled towards the surface.
They occur when winds blow across the surface of the ocean, pushing water away. Water from deep below then rises up to take its place, creating an upward current.
These are important because this cold water contains lots of nutrients.
The upwelling fertilises the shallower parts of the ocean, creating food for fish and helping to keep the ecosystem healthy.Â
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‘And indeed, we can trace its effects on coastal ecology and humans in the region back to at least 11,000 years.’
Using satellite measurements, the researchers have already begun to track the profound effect that this failure has had on the marine ecosystem.
Normally, the surge of nutrient-rich water triggers such rapid growth of algae and plankton that researchers can see it from space.
But this year, that bloom of life is almost entirely absent, which could be disastrous for the fish that feed on those microscopic organisms and the people whose livelihoods depend on the rich ocean life.
Without a steady supply of cold water, the regions ecologically important coral reefs are also under threat.
When coral becomes too hot, it expels the tiny ‘zooxanthellae’ algae which live inside its structures.
This algae normally gives the coral its colour and provides them with a source of food.
With the algae gone, the coral turns white and eventually dies in a process called coral bleaching.
Without a supply of cold water, scientists are concerned that the region’s vital coral reefs (pictured) will be killed by the warmer waters in a process known as coral bleachingÂ
Scientists studying the upwelling aren’t yet sure whether this is a one-off event caused by this year’s La Niña conditions, or a more permanent change that could have disastrous ecological and economic consequences
If the Panama Pacific upwelling does not resume, it could lead to widespread coral bleaching across the entire region. Â
Scientists believe that the failure was due to a ‘dramatic reduction’ in northerly winds, with 74 per cent fewer winds that had a much shorter duration when they did occur.
‘When winds formed, they were as strong as ever, but there simply weren’t enough of them to drive the upwelling process,’ says Dr O’Dea.
However, Dr O’Dea says that the ‘critical unknown’ is whether this failure is a one-off event or the beginning of a new normal.
The researchers suspect that the change may be linked to this year’s La Niña conditions, a cyclical period of cooler ocean surface temperatures.
But the changes could also be part of a more permanent shift in global weather patterns caused by climate change.
The researchers hope that the answer to this question will become clearer as more studies of these tropical ocean currents develop.
Dr O’Dea concludes: ‘Climate disruption can upend seemingly predictable processes that coastal communities have relied upon for millennia.’
WHAT IS THE EL NINO PHENOMENON IN THE PACIFIC OCEAN?
El Niño and La Niña are the warm and cool phases (respectively) of a recurring climate phenomenon across the tropical Pacific – the El Niño-Southern Oscillation, or ‘ENSO’ for short.
The pattern can shift back and forth irregularly every two to seven years, and each phase triggers predictable disruptions of temperature, winds and precipitation.Â
These changes disrupt air movement and affect global climate.Â
ENSO has three phases it can be:Â
El Niño: A warming of the ocean surface, or above-average sea surface temperatures (SST), in the central and eastern tropical Pacific Ocean. Over Indonesia, rainfall becomes reduced while rainfall increases over the tropical Pacific Ocean. The low-level surface winds, which normally blow from east to west along the equator, instead weaken or, in some cases, start blowing the other direction from west to east. La Niña: A cooling of the ocean surface, or below-average sea surface temperatures (SST), in the central and eastern tropical Pacific Ocean. Over Indonesia, rainfall tends to increase while rainfall decreases over the central tropical Pacific Ocean. The normal easterly winds along the equator become even stronger.Neutral: Neither El Niño or La Niña. Often tropical Pacific SSTs are generally close to average.
Maps showing the most commonly experienced impacts related to El Niño (‘warm episode,’ top) and La Niña (‘cold episode,’ bottom) during the period December to February, when both phenomena tend to be at their strongest
Source: Climate.gov