by For many people, 2023 – confirmed by NASA as the hottest on record – was characterized by extreme weather, sweltering heat waves and wildfires. Climate scientists also saw them as fearful viral chart on social media showing how far North Atlantic sea surface temperatures have deviated from the historical average.
Dr Thomas Smith, associate professor of environmental geography at the London School of Economics, first shared the chart in April and it was one of many alarming ones showing that the surface temperature of the world’s oceans was at a record high – and didn’t. ‘t shows any signs of abatement.
This is so unusual. That’s a *huge* amount of energy being transferred to the atmosphere. Expect extreme temperatures and storm records. Just the few meters on top of our oceans store as much energy as our entire atmosphere. I’m really worried later this year into 2024. https://t.co/7rfyJeZMaA
— Dr. Thomas Smith 🔥🌏 (@DrTELS) April 24, 2023
Increases in sea surface temperature (SST) are important, as the US Environmental Protection Agency puts it, because they can have “profound impacts” on global climate. They could lead to an increase in the amount of atmospheric water vapor over the oceans and, in turn, a greater chance of extreme weather events such as heavy rain and snow.
In addition, they can change storm tracks, which can contribute to droughts in some areas, as well as increase the growth of bacteria, which can contaminate seafood and cause foodborne illnesses.
In fact, Tuesday’s Bulletin of the Atomic Scientists cited SST as one of the reasons its “Doomsday Clock” has been set as close to midnight as ever.
On 21 January 2024, said Dr Smith shared update to his viral post from 2023, saying: “This tweet went viral and made the news in June 2023, two months after my first concern about sea surface temperatures.”
He went on to share this updated version of the chart, which is not pleasant to look at.
“Seven months have gone by and the North Atlantic has spent 321 consecutive days breaking daily SST records. .
So why are broken records so consistently seen in 2023 and 2024?
Last year, El Niño – a climate pattern that occurs every two to seven years – was seen to raise surface air temperatures, and a high pressure system over the Atlantic will have made a difference.
However, there may be another factor involved, according to Dr. Smith, which he and other scientists say may have been overlooked for years.
He told Yahoo News UK this week: “In recent years there seems to be a lot more sunlight being absorbed by the surface of the ocean. This coincides with the changing regulations for shipping fuel, and I think it would be prudent not to ignore that coincidence.”
The decision taken in 2020 to clean up international shipping by cutting sulfur oxide emissions was made to improve air quality and protect people’s health from this hazardous gas. Dr Smith warns, however, that it could have an unintended impact on climate change that has been “hidden” for years.
“We know that aerosols – particles in air pollution – are important for reflecting sunlight. [They] also important for cloud formation, which reflects sunlight in the lower parts of the atmosphere.” This means, he says, that pollution probably “helped keep us cooler than it would have been otherwise”.
“This had a much greater effect during the 1950s and 1960s when industry and transport were much more polluting than today, and we think that may have slowed the greenhouse warming a few decades before we started cleaning the atmosphere.
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“But when we start cleaning up the atmosphere of particulate pollution, the warming effect of carbon dioxide then starts to dominate the global temperature pattern.”
Although there is no unanimous scientific consensus on this possible phenomenon, Dr Smith points to a 2023 study, published in Oxford Open Climate Change, which describes this trade-off between less air pollution and increased warming as a “Faustian bargain”. The paper suggests that the reduction in aerosol emissions since 2010 should increase the rate of warming, meaning we could reach 2C above pre-industrial levels by 2050.
“Obviously, we’d really like to avoid that by 2100, so if that happens earlier we could be in for extreme weather,” Dr Smith said. He warned that hitting 2C by the middle of this century would be “much faster than most governments are planning for”.
How could we get out of this?
The best option is to get to net zero as soon as possible, says Dr Smith, adding: “It’s really important to understand that the long-term problem here is greenhouse gases.”
Others believe geoengineering is another possible solution, which Dr Smith stressed he does not support. “That could include reintroducing particles into the ocean atmosphere, but perhaps cleaner particles like salt crystals. So using fine sea spray to help create clouds that have disappeared leading to cleaner fuels.”
He says “bigger” options include sending aerosols into the stratosphere, such as volcanic eruptions, which could contribute to temporary cooling. “Some people are again proposing to continuously spray the stratosphere with these demonstrated articles to offset the greenhouse warming and give us a little time to reach net zero.”
Ultimately, Dr Smith says we should all be making decisions as individuals to reduce our CO2 emissions, and says governments should be introducing carbon taxes to help offset measures to finance. “There is very little incentive for people to reduce their carbon footprint.” he adds.
‘More than an inconvenience’
When asked what we could expect in the worst case scenario, with global temperatures rising above 2C by mid-century, the worst case scenario is worrying.
“Food and water security is your biggest concern,” explains Dr Smith. “This is why people need to worry about 2C warming. We are not talking about inconvenience.
“We are talking about whether you can buy food in the supermarket or whether you have clean water coming from your tap. We already have problems in some places with 1C of heating. We could be looking at the loss of 30 -40% of world carbohydrate production with 2.5C.”
Dr Smith is not the only one saying this. A recent NASA study warned that if temperatures stay above 2C, we could be facing multiple problems at the same time. “The cumulative impacts of all climate extremes studied could cause significant damage to communities and economies, due to fires, floods, landslides, and crop failures that may occur,” he says.
Parliamentary research also warns that climate change means ‘violent displacement’ due to extreme and frequent weather events is expected to increase, with the most difficult regions expected to become uninhabitable due to impacts ‘ slow’ of climate change.
Dr Smith says: “We’re not talking about small changes you might have to make. It’s basically whether you can buy food in an import-dependent economy. I’d rather we don’t go that far… I’d rather we maintain our security, and part of that includes mitigating climate change as quickly as we can.”
