New Study Warns of an Imminent Spike of Planetary Warming and Deepens Divides Among Climate Scientists - Inside Climate Newshttps://insideclimatenews.org/news/02112023/study-warns-of-spike-of-warming-divides-climate-scientists/the research was controversial even before it was published, and it may widen the rifts in the climate science community and in the broader public conversation about the severity and imminence of climate impacts, with Hansen criticizing the United Nations Intergovernmental Panel on Climate Change for underestimating future warming, while other researchers, including IPCC authors, lambasted the new study.
The research suggests that an ongoing reduction of sulfuric air pollution particles called aerosols could send the global average annual temperature soaring beyond the targets of the Paris climate agreement much sooner than expected, which would sharply increase the challenges faced by countries working to limit harmful climate change under international agreements on an already treacherous geopolitical stage.
...
Combining the the paleoclimate data with modeling and detailed observations from the last few decades, the team concluded that the world is in for a wild ride of climate impacts, including possible superstorms that could toss house-sized boulders to the top of seaside cliffs, radical changes to global rainfall patterns that would affect agriculture in densely populated regions and possibly several meters of sea level rise by 2100, as compared to the IPCC-projected range of .29 to 1.1 meters.
...
Hansen’s new research about the relative strengths of those competing effects diverges from many other studies by suggesting the cooling effect has been underestimated so that as sulfur aerosols and their effects on clouds are reduced, temperature will increase more than expected.
How clouds will change in the decades ahead, and their interaction with aerosols, remains the single greatest uncertainty in making accurate projections for future temperature increases, according to most climate scientists. Several key satellite instruments that could have helped answer that question never made it into orbit in the 1980s and 1990s, despite repeated requests, Hansen said.
...
Schmidt said a new mission called PACE (short for Plankton, Aerosol, Cloud, ocean Ecosystem) could quickly reduce the uncertainties surrounding the effects of aerosols on the climate. That satellite should be in orbit within the coming year. Copernicus, the European Union climate change service, is also launching a new satellite, EarthCARE, also with the goal of measuring the relationship of aerosols, clouds and precipitation to how much of the sun’s radiation reaches Earth to drive global heating.
Absent those data, the new study used a process of elimination to again show reductions in sulfur aerosols were triggering accelerated warming. Comparisons with past climate periods hold some of the clues, showing, for example, that reefs along the Yucatán Peninsula grew upward and shoreward in giant spurts over the course of just a few decades, about 100,000 years ago during the late Eemian geological era. That, Hansen said, is another warning sign that parts of Earth’s climate system, and particularly ice sheets and ice shelves, are more sensitive to warming than we think.
“The IPCC system doesn’t acknowledge the degree to which the aerosol forcing will affect the climate in the next few decades, probably more than anything else,” Simons said. “We hope we’re wrong.”