The fate of the West Antarctic Ice Sheet (WAIS) hangs precariously in the balance, with scientists warning that the next few years will be crucial in determining its future. A recent study published in Communications Earth & Environment has shed light on the alarming consequences of WAIS collapse, which could trigger a devastating four meters of global sea level rise over hundreds of years.

The researchers from the Potsdam Institute for Climate Impact Research (PIK), NORCE, and Northumbria University in the UK conducted extensive model simulations spanning 800,000 years to understand how the vast Antarctic Ice Sheet has responded to Earth’s climate fluctuations. Their findings revealed two stable states: one with WAIS intact, which is our current state, and another where the ice sheet has collapsed.

The primary driver of this collapse is rising ocean temperatures around Antarctica, which are mostly supplied by the ocean rather than the atmosphere. Once WAIS tips into the collapsed state, it would take several thousands of years for temperatures to drop back to pre-industrial conditions, reversing the damage.

“We have two stable states: one with WAIS intact and another where it has collapsed,” said lead author David Chandler from NORCE. “Once tipping has been triggered, it’s self-sustaining and seems very unlikely to be stopped before contributing to about four meters of sea-level rise. And this would be practically irreversible.”

The consequences of WAIS collapse would be catastrophic, with four meters of sea level rise projected to displace millions of people worldwide and wreak havoc on coastal communities.

However, there is still hope for a better outcome. Immediate actions to reduce emissions could avoid a catastrophic outcome, giving us a narrow window to act before it’s too late.

“It takes tens of thousands of years for an ice sheet to grow, but just decades to destabilise it by burning fossil fuels,” said co-author Julius Garbe from PIK. “Now we only have a narrow window to act.”

The persistent presence of nitrates in the atmosphere has long been a concern for environmental scientists. Despite efforts to reduce emissions over the past few decades, nitrate levels remain stubbornly high. A recent study published in Nature Communications sheds light on this enigma, revealing that chemical processes within the atmosphere are responsible for the persistence of these pollutants.

The research team led by Hokkaido University’s Professor Yoshinori Iizuka examined nitrate deposition history from 1800 to 2020 in an ice core taken from southeastern Greenland. The results showed a gradual increase in nitrates up to the 1970s, followed by a slower decline after the 1990s. This trend mirrors the changes in emissions of nitrate precursors over the same period.

The study’s findings suggest that factors other than emission reductions are driving the persistence of atmospheric nitrates. The researchers used a global chemical transport model to investigate these factors and discovered that atmospheric acidity is the key culprit. As acidity levels rise, more nitrates become trapped in particulate form, enabling them to persist longer and travel farther.

The implications of this study are significant. Accurate measurements of particulate nitrates in ice cores provide valuable data for refining climate modeling predictions. Moreover, the findings suggest that atmospheric nitrates will soon replace sulfates as the primary aerosol in the Arctic, further amplifying warming in the region.

As Professor Iizuka notes, “Ours is the first study to present accurate information for records of particulate nitrates in ice cores.” The persistence of these pollutants highlights the importance of continued research into atmospheric chemistry and climate modeling. By understanding the complex interactions within our atmosphere, we can better predict and prepare for the challenges that lie ahead.

The world’s food supply is facing unprecedented challenges due to Earth’s rapidly changing climate. University of Hawai’i scientists are among a team of researchers who have discovered an innovative way to help adapt food crops around the world to these new conditions. A recent study published in Nature Climate Change reveals how plant genebanks, also known as “living libraries,” can speed up the process of breeding crops better suited for climate change.

These living libraries store seeds and other genetic material from millions of genetically diverse plants worldwide. They provide a vital resource for plant breeders working to develop new crop varieties that have traits such as drought resistance, disease tolerance, or improved yields. The researchers used sorghum, a grain grown for food, fuel, and livestock feed, to test a new method called environmental genomic selection.

This approach combines DNA data with climate information to predict which plants are best suited for future conditions. It can be applied to any crop that has the right data, including sorghum, barley, cannabis, pepper, and dozens of other crops. By using a smaller, diverse “mini-core” group to forecast how crops will perform in different environments, scientists can quickly select the best parents for new, climate-resilient varieties.

“This method will help us keep pace with the hotter temperatures and increased risk of flooding from Earth’s changing climate and help develop new varieties to ensure food security,” said co-author Michael Kantar of the UH Manoa College of Tropical Agriculture and Human Resilience (CTAHR).

The researchers also discovered that nations with high sorghum use may need genetic resources from other countries to effectively adapt to climate change. This highlights the value of global teamwork in securing the world’s food supply.

In conclusion, living libraries can play a crucial role in helping us adapt food crops to climate change. By leveraging these genetic resources and innovative breeding techniques, we can develop more resilient crop varieties that will ensure global food security for generations to come.