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Global heat has seared to new extremes in recent months, and devastating climate disasters are providing powerful reminders of the costs of climate change, as governments around the world prepare for the 2023 United Nations climate summit that starts on Nov. 30. While a small window of hope remains for meeting the goals of the 2015 Paris climate agreement, the world’s greenhouse gas emissions continue to rise. This year’s climate summit, COP28, needs to be transformative. What will it take to harness a spirit of international cooperation in today’s complex, divisive and volatile world abounding in self-interest? As a former senior U.N. official, I worked for years in multilateral consensus building among often hugely divergent parties. Here are some of the challenges and negotiating techniques I expect to see as representatives from countries around the world come together in Dubai. The challenge of national self-interest To slow climate change, the world m...

Air pollution particles from coal-fired power plants are more harmful to human health than many experts realized, and it’s more than twice as likely to contribute to premature deaths as air pollution particles from other sources, new research demonstrates. In the study, published in the journal Science, colleagues and I mapped how U.S. coal power plant emissions traveled through the atmosphere, then linked each power plant’s emissions with death records of Americans over 65 years old on Medicare. Our results suggest that air pollutants released from coal power plants were associated with nearly half a million premature deaths of elderly Americans from 1999 to 2020. It’s a staggering number, but the study also has good news: Annual deaths associated with U.S. coal power plants have fallen sharply since the mid-2000s as federal regulations compelled operators to install emissions scrubbers and many utilities shut down coal plants entirely. In 1999, 55,000 death...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com. How do crystals form? – Alyssa Marie, age 5, New Mexico Scientifically speaking, the term “crystal” refers to any solid that has an ordered chemical structure. This means that its parts are arranged in a precisely ordered pattern, like bricks in a wall. The “bricks” can be cubes or more complex shapes. I’m an Earth scientist and a teacher, so I spend a lot of time thinking about minerals. These are solid substances that are found naturally in the ground and can’t be broken down further into different materials other than their constituent atoms. Rocks are mixtures of different minerals. All minerals are crystals, but not all crystals are minerals. Most rock shops sell mineral crystals that occ...

Thousands of earthquakes in recent weeks have shaken the Icelandic fishing town of Grindavík, about 30 miles (50 kilometers) southwest of the capital Reykjavik. They have triggered evacuations and warnings that a volcanic eruption may be imminent. While the idea of magma rising was no doubt scary for tourists visiting the nearby Blue Lagoon geothermal spa, which was closed as a precaution, Iceland’s residents have learned over centuries to live with their island’s overactive geology. So, why is Iceland so volcanically active? The answer has two parts: One has to do with what geologists unimaginatively call a hotspot, and the other involves giant tectonic plates that are pulling apart right beneath the island. As a geologist, I study both. Eruptions in this region of Iceland tend to flow rather than being explosive, as residents saw in July 2023 and in 2021-22. Kristinn Magnusson/AFP via Getty Images...

As renewable energy production expands across the U.S., the environmental impacts of these new sources are receiving increased attention. In a recent report, the National Academies of Sciences, Engineering, and Medicine examined whether and how constructing offshore wind farms in the Nantucket Shoals region, southeast of Massachusetts, could affect critically endangered North Atlantic right whales. The Conversation asked marine scientists Erin L. Meyer-Gutbrod, Douglas Nowacek, Eileen E. Hofmann and Josh Kohut, all of whom served on the study committee, to explain the report’s key findings. Why did this study focus on such a specific site? The Bureau of Ocean Energy Management, which is part of the U.S. Department of the Interior and regulates offshore energy production, asked the National Academies to conduct this study. Regulators wanted to better understand how installing and operating offshore, fixed-bottom wind turbine generators would affect physical oceanographic pr...