Climate change causes intensification of ocean color: MIT study


Scientists say that the colors of the world's oceans will intensify by the end of the century because of climate change, threatening the marine ecosystem from the bottom up.

The color of 50% of the oceans will change by 2100 because of changes in phytoplankton communities, according to a Massachusetts Institute of Technology study published earlier this month in Nature Communications. Scientists have said that blue water in subtropical areas will appear bluer, while greener water near the poles will appear greener.

The phytoplankton, or algae, that scientists talk about are small, vital marine organisms which can change population depending on the temperature of the ocean, which, according to several climate studies, is increasing rapidly. The study used a climate model projecting changes in the ocean throughout the century and showed changes in the color of the ocean in a world at 3 degrees Celsius warmer. that scientists are already predicting will happen by 2100.

Water molecules absorb all parts of the sunlight, except for the blue wavelengths, which reflect and give the ocean its blue hue. Phytoplankton contains a green pigment called chlorophyll. For example, ocean surfaces with high populations of phytoplankton appear greener and areas with less phytoplankton are more blue.

According to the study, climate change would lead to the proliferation of phytoplankton in some ocean regions, while reducing it in others, resulting in changes in the color of the water. Warming in subtropical areas could deprive phytoplankton of nutrients and reduce their population, but warming in polar areas could provide a better environment for their growth. Scientists have said that color changes would be too gradual for an average individual to be able to report over time, but this change is a much more important revelation of the other problems in the world. ocean.

"It could be potentially very serious," lead author Stephanie Dutkiewicz said in a press release. "If climate change moves one phytoplankton community to another, it will also change the types of food webs that they can support."

Phytoplankton is the basis of the food chain of marine life. A decrease in algae could therefore trigger a reaction that would affect fish populations in the ocean. Algae also absorb atmospheric carbon dioxide for photosynthesis. Therefore, a reduction in phytoplankton could result in more carbon dioxide in the air.

The study says it takes some time before scientists can correctly predict the impact of climate change on phytoplankton communities. The best method is to pay attention to changes in the color of the ocean.

"Changes are happening because of climate change," said Dutkiewicz. said the Washington Post. "It will take some time before we can statistically show that. But the color change of the ocean will be one of the warning signals that we have actually changed our planet. "


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