A red line on a graph has caught the attention of many on social media in recent days. The line, which shows sea surface temperatures in the North Atlantic, points straight up. It shows the ocean area was almost 1.09 degrees Celsius above average – on a scale dating back to 1982, the earliest year with comparable data. – I have been working on this for a long time, but I thought: “Oh God, look at this. What is happening now?” The Twitter message has been viewed almost 3 million times. Photo: @EliotJacobson / Twitter So says Eliot Jacobsen, a retired math professor, to the Los Angeles Times. He has created the graph using data from the Institute for Climate Change at the University of Maine. The data is correct and based on satellite measurements which have great accuracy, confirms Tore Furevik, professor of climate dynamics at the University of Bergen. The Atlantic basin is experiencing abnormal heat, and that both confirms and frightens, he says. – Given that we have never before seen such large temperature and sea ice deviations from normal, it is of course highly abnormal. And although we could expect new records this year, there are many who are surprised and worried about how big these new records have become, says Furevik. – Could this have happened without man-made climate change? – No, it would not have been possible to have such large deviations from the normal without the man-made climate changes, he says. – It is clear that the graphs clearly show that we now have a climate that we have never seen before, and with heat records far higher than all previous measurements. It both confirms and scares, says Tore Furevik, director of the Nansen Center and professor at the University of Bergen. Photo: Sindre Skrede / news Three reasons The early arrival of El Niño is only partly to blame for the red line pointing straight up. Professor Tore Furevik lists three reasons: Man-made climate change Our emissions of greenhouse gases lead to an increasingly powerful greenhouse effect, and this increases the global average temperature by approx. 0.2 degrees Celsius per decade. The high temperatures would not have been possible without man-made emissions. Photo: news El Niño situation In the last three years, global warming has been “slowed down” by the fact that it has been abnormally cold in the Pacific Ocean. This is called La Niña. Already this autumn, the climate models showed that the cold La Niña is now being replaced by an abnormally warm period in the Pacific Ocean, a so-called El Niño situation, and this is helping to “accelerate” the man-made climate changes. Photo: Climate Change Institute / University of Maine Abnormal ocean currents Random variations in the weather, i.e. where there is high pressure and low pressure, where there is a north wind and where there is a south wind, where there are stronger or weaker ocean currents than normal, will also affect surface temperatures in the ocean. If you look more closely at the figures, you will see that there are many variations over days, weeks and months. There is reason to believe that this has also contributed to the big results we have seen in recent weeks. The graph shared by Jacobsen on Twitter shows figures for deviations from the normal. That is, it shows how much warmer the sea is in 2023 compared to a normal year. But also in the graph below, which shows temperatures day by day, 2023 is a step up from all other years that have been measured. The black line shows the temperatures in the North Atlantic in 2023 so far. Photo: Climate Change Institute / University of Maine Volcanic eruptions Daniel Swain, a climate scientist at the University of California Los Angeles, says another potential factor could be the recent eruption of an undersea volcano in Tonga. – We now have a natural volcanic eruption which is likely to result in very short-term global warming. It comes on top of the human-caused warming we’re already seeing. This may be part of the reason for the increase right now in some global ocean and atmospheric temperatures, Daniel Swain believes. Enormous consequences – What damage can these high temperatures do to the ocean? – High temperatures in the sea can cause enormous damage to marine life. Fish species are disappearing, tropical coral reefs are dying out, and large areas may suffer from a lack of oxygen, says Furevik. – What does this mean for sea ice? – Warmer seas contribute to sea ice melting faster. And this has an amplifying effect, since less ice means less sunlight is reflected (the ocean is much darker than the ice), and this provides additional warming. – Warmer water also contributes to glaciers that reach the sea, e.g. in Greenland and Antarctica, is melting faster and that is helping to reinforce the problem of global sea level rise, says Furevik. Photo: Climate Change Institute / University of Maine
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What happens to the ocean? – news – Climate
