Volcanic eruptions have periodically cooled the tropics over at least the last 450 years by spewing out particles that girdle the world at high altitude and reflect sunlight, a study released yesterday said.
The research adds a chunk of regional evidence to earlier work that found major eruptions — such as Krakatoa, Indonesia in 1883 and Huaynaputina, Peru in 1600 — contribute to cooling on a worldwide scale.
A trio of scientists led by Rosanne D’Arrigo of the Lamont-Doherty Earth Observatory in Palisades, New York, looked at ocean temperatures in a belt extending from 30 degrees south across the equator to 30 degrees north.
They compiled temperature records reaching back nearly half a millennium from three sources: ice cores, tree rings and coral reefs.
They found the longest sustained period of cooling of sea surfaces — to a depth of 1m — occurred in the early 1800s following the eruption of Mount Tambora on the Indonesia island of Sumbawa.
Tambora blew its top in 1815 and was the most powerful eruption in recorded history, the US Geological Survey said. But links between volcanic activity and cooler ocean surfaces weakened in the 20th century, apparently as a result of global warming from the burning of fossil fuels, the researchers said.
Another study, also published online in the journal Nature Geoscience, points to a previously unrecognized potential driver of climate change.
Intensive, chemical-laden agriculture could trigger the release of carbon dioxide from river systems, Henry Wilson and Marguerite Xenopoulos of Trent University in Ontario, Canada argue.
The researchers examined organic matter that had dissolved in 34 rivers in Ontario.
Some of the rivers were pristine and others were heavily polluted by runoff from agricultural chemicals such as fertilizers. Pollution from these chemicals meant the organic material was likelier to release its carbon into the atmosphere, the study said.
North Korean leader Kim Jong-un sent Chinese President Xi Jinping (習近平) greetings with what appeared to be restrained rhetoric that comes as Pyongyang moves closer to Russia and depends less on its long-time Asian ally. Kim wished “the Chinese people greater success in building a modern socialist country,” in a reply message to Xi for his congratulations on North Korea’s birthday, the state-run Korean Central News Agency reported yesterday. The 190-word dispatch had little of the florid language that had been a staple of their correspondence, which has declined significantly this year, an analysis by Seoul-based specialist service NK Pro showed. It said
On an island of windswept tundra in the Bering Sea, hundreds of miles from mainland Alaska, a resident sitting outside their home saw — well, did they see it? They were pretty sure they saw it — a rat. The purported sighting would not have gotten attention in many places around the world, but it caused a stir on Saint Paul Island, which is part of the Pribilof Islands, a birding haven sometimes called the “Galapagos of the north” for its diversity of life. That is because rats that stow away on vessels can quickly populate and overrun remote islands, devastating bird
‘CLOSER TO THE END’: The Ukrainian leader said in an interview that only from a ‘strong position’ can Ukraine push Russian President Vladimir Putin ‘to stop the war’ Decisive actions by the US now could hasten the end of the Russian war against Ukraine next year, Ukrainian President Volodymyr Zelenskiy said on Monday after telling ABC News that his nation was “closer to the end of the war.” “Now, at the end of the year, we have a real opportunity to strengthen cooperation between Ukraine and the United States,” Zelenskiy said in a post on Telegram after meeting with a bipartisan delegation from the US Congress. “Decisive action now could hasten the just end of Russian aggression against Ukraine next year,” he wrote. Zelenskiy is in the US for the UN
A 64-year-old US woman took her own life inside a controversial suicide capsule at a Swiss woodland retreat, with Swiss police on Tuesday saying several people had been arrested. The space-age looking Sarco capsule, which fills with nitrogen and causes death by hypoxia, was used on Monday outside a village near the German border. The portable human-sized pod, self-operated by a button inside, has raised a host of legal and ethical questions in Switzerland. Active euthanasia is banned in the country, but assisted dying has been legal for decades. On the same day it was used, Swiss Department of Home