Scientists warn: ocean memory is eroding due to climate change

With climate change, the oceans around the world are changing and this is manifested in clear anomalies not only in the ocean's temperature , but in its structure, currents and even its color. In turn, these changes make it difficult to predict the conditions of the ocean environment, which were often stable.

In a research paper published on May 6 - in the journal Science Advances - researchers from the Farallon Institute in Petaluma, California, liken this phenomenon to the loss of the ocean's memory.

ocean memory

According to a report published on the "Science Alert" website, researchers defined the term "ocean memory" as "the continuity of ocean conditions measured by monitoring the rate of changes in sea surface temperatures from year to year, making it a major source due to the predictability of the climate system beyond the time scales of weather” and the researchers predicted that “the ocean memory will decline steadily over the coming decades in most parts of the world.”

The researchers studied sea surface temperatures in the upper surface layer of the ocean, which is called the upper oceanic mixed layer. Although they extend only about 50 meters below the ocean, they show constant rates of thermal inertia over time, compared to changes seen in the atmosphere above them. Thermal inertia is defined as the property of a substance in maintaining its heat and releasing it little by little.

The researchers suggest that the "memory" effect of thermal inertia in the upper ocean will decrease over the coming years globally, with significantly larger temperature differences expected over the coming decades.

Thermal inertia

According to the researchers, the change in surface water will effectively reduce the depth of this layer. This is expected to lower the ocean's capacity for thermal inertia, making the upper ocean more vulnerable to random changes in temperature.

The researchers stated that the effect of the decrease in the thermal inertial property of the oceans on terrestrial and marine life is not yet precisely clear, but they are likely to have an impact on the behavior of terrestrial and marine organisms, and the adaptive performance of some species may be better than others.

On the other hand, the researchers expected that the decline in ocean memory would make it more difficult for scientists to predict upcoming ocean dynamics , thus questioning the reliability of the proposed time periods for all kinds of sea-surface weather predictions. This in turn will hinder our ability to anticipate monsoons, marine heat waves, periods of severe weather, and other phenomena.

"The projected decrease in ocean memory is likely to hamper ocean forecasting efforts by reducing the sure time periods for predicting sea surface temperature. Changes in surface waters due to global warming may alter the extreme temperature statistics which in turn are associated with a time limit," the researchers wrote. “less” predictions based on persistence of ocean surface conditions, which poses a challenge to ecosystem management and preparedness for marine hazards.”