- A study by researchers at the Massachusetts Institute of Technology and the National Oceanography Center found that over 56% of the world’s oceans have shifted color over the past 20 years, possibly due to human-caused climate change.
- The study used data from NASA’s Aqua satellite and found that tropical ocean regions near the equator have been impacted by the gradual transition from blue to green.
- The study suggests that the effects of climate change are already being felt in surface marine microbial ecosystems.
- The study’s co-author, Stephanie Dutkiewicz, believes that changes in color reflect changes in plankton communities and the ocean’s ability to absorb carbon.
The color of more than 56 percent of the oceans around the globe has quietly shifted during the past 20 years, and it seems likely that climate change brought on by humans is to blame.
This is according to a new study that was conducted by researchers at the Massachusetts Institute of Technology and the National Oceanography Center in the United Kingdom. The study concluded that the phenomenon cannot be explained by natural variability alone. This finding has driven the news.
What they did: As color changes can be too faint for the human eye to notice, the researchers studied data from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite for the study, which was published in the journal Nature on Wednesday.
According to the findings of the research, tropical ocean regions located close to the equator have been notably impacted by the gradual transition from blue to green in the color of the water.
According to a statement issued by MIT that accompanied the study, “The shift in ocean color indicates that ecosystems within the surface ocean must also be changing, as the color of the ocean is a literal reflection of the organisms and materials in its waters,”
The findings “suggest that the effects of climate change are already being felt in surface marine microbial ecosystems,” the researchers wrote in their report.
In between the lines: “Much of the ocean appears blue to our eye, whereas the true color may contain a mix of subtler wavelengths, from blue to green and even red,” as stated by MIT.
In general, waters that are deep blue represent relatively little life, whereas waters that are greener suggest the presence of ecosystems, and more specifically phytoplankton, which are plant-like microorganisms that are plentiful in the upper ocean and that carry the green pigment chlorophyll.
Noteworthy is the fact that one of the study’s co-authors, Stephanie Dutkiewicz, a senior research scientist at MIT’s Department of Earth, Atmospheric and Planetary Sciences and the Center for Global Change Science, stated in a statement that researchers were unable to determine how the color of the water had changed.
She stated that “but we can say that changes in color reflect changes in plankton communities,” and that these changes would have an effect on everything that feeds on plankton.
In addition, “it will also change how much the ocean will take up carbon, because different types of plankton have different abilities to do that,” Dutkiewicz added. “Not only do models forecast that these changes will take place, but so do other sources. We are now in a position to see that it is occurring, and the ocean is undergoing change.
This is what they have to say: Kevin Trenberth, a distinguished scholar at the National Center for Atmospheric Research, stated that the findings connected to a study that he was part in for the year 2020 reveal that the upper global ocean has gotten more stratified and stable over the previous few decades as a result of global warming.
Trenberth, who was not participating in the most recent study, pointed out that the researchers “do not sort out the large effects” of the El Nio-Southern Oscillation (ENSO) and that the previous three years were dominated by a significant La Nia event. Trenberth did not take part in the most recent study.
In spite of this, Trenberth referred to the study as “a useful start to detailing the consequences of the changes in the upper ocean and marine ecosystems associated with climate change.”
