Leading climate scientists have warned that global warming is accelerating at a faster rate due to a previous attempt to curb climate change.
James Hansen, formerly Director of the NASA Goddard Institute for Space Studies, released a new study this month, claiming rules to reduce sulfur emissions emitted by ships, cars and electric utilities are hurting our planet.
The landmark Clean Air Act in 1970 triggered the movement to regulate pollution from cars and other forms of transportation, including ships.
In 2020, global standard-restricted shipping rules reduced fuel sulfur from 3.5 percent to 0.5 percent, which experts said is dramatically attributing to global warming.
The sulfur-containing exhaust helps create clouds over the ocean that push heat back into space as aerosols, but the seas capture the warmth and increase temperatures faster.
Hansen and many other scientists said that type of more traditional sooty air pollution has a cooling effect that masks a fraction of the warming from burning coal, oil and natural gas.
A new study has claimed rules to reduce sulfur emissions emitted by ships and fossil fuel plants are hurting our planet by increasing temperatures at a faster rate
NASA released a study in 2022 that a global standard implemented by the International Maritime Organization (IMO) led to fewer pollution fingerprints worldwide.
This was likely achieved by reduced ship track formation.
‘The 1.5C [2.7F] limit is deader than a doornail,’ said study co-author Hansen of Columbia University’s Earth Institute, who was among the first scientists to alert the world in the 1980s to the climate-warming impact of greenhouse gases.
‘The shortcoming of our scientific community is to not make clear to the political leaders what the situation is.’
The world already has warmed by nearly 2.2F (1.2C) above preindustrial temperatures, according to experts.
The study found that scientists have underestimated how sensitive the Earth’s climate is to rising carbon dioxide levels.
However, despite his advocacy, Stanford University climate scientist Rob Jackson said: ‘I tend to trust Hansen.
‘I think his contention that the IPCC [Intergovernmental Panel on Climate Change] has underestimated climate sensitivity will prove out.’
The sulfur-containing exhaust helps create marine clouds that push heat back into space in the form of aerosols, but the oceans are capturing the warmth and increasing temperatures faster
University of Pennsylvania climate scientist Michael Mann, who insisted that since 1990, warming has been steadily increasing but not accelerated, posted a rebuttal to Hansen’s claims and said climate change right now is bad enough and there is no need to overstate the case.
Mann said, ‘It has always been risky to ignore (Hansen´s) warnings and admonitions,’ but when claims are made so out of the mainstream, the standard for evidence is high, and he said Hansen has not met them.
However, a National Oceanic and Atmospheric Administration (NOAA) data check supports Hansen’s modeling.
Hansen and his team looked at climate data from 1970 to 2010, finding the world warmed at 0.32F (0.18C) per decade, projecting that it would be 0.5F (.27C) per decade after 2010 – and NOAA’s data confirmed this model.
That starting date is key because that’s when scientists could start to see the effect of clean air regulations that reduced aerosol pollution and the amount of sulfur in fuel used by ocean shipping, Hansen said.
Study author James Hansen said Earth’s energy imbalance is much higher than a decade ago
Another factor cited by the report relates to China’s progress in cleaning up air pollution, caused mainly by sulfur dioxide spewed from coal plants, alongside global efforts to curb such emissions from shipping.
Cleaning the skies while bringing health benefits and saving lives accelerates climate change. Aerosols scatter and reflect solar radiation.
Past calculations were based on plant and animal fossil data, figuring microbiotic organisms would not adapt to warming but would move to their preferred temperature range.
Hansen said recent research shows that the microorganisms adapt and stay put.
When his team calculated past temperature changes based on chemical, not biological, markers, it showed much faster warming for when carbon dioxide doubled in Earth’s ancient history.
Hansen said Earth’s energy imbalance is much higher than a decade ago.
‘That imbalance has now doubled. That’s why global warming will accelerate. That’s why global melting will accelerate,’ he said.
When asked if this was evidence of the extreme warming we’ve seen over the past five months, Hansen replied, ‘Yeah. Absolutely it is.’