Earthweek: a diary of the planet
For the week ending Friday, Jan. 19.
Arctic churnings
Dramatic climate change in the Arctic in the past few years is threatening to have significant impacts on the region’s coastal food webs and animal populations, a new study reveals. Researchers found that the record melt of sea ice has increased wave action on the shallow Arctic coastal shelves, which is probably stirring up nutrients, carbon and other chemicals stored in the coastal sediment. The scientists made the conclusion after finding levels of radium-228 in the middle of the Arctic Ocean had doubled over the past decade. Researchers believe the naturally occurring isotope was also stirred up by increased costal wave action and carried by currents.
Climate survival
The existence of the human species is now threatened more by extreme weather in a changing climate than by weapons of mass destruction, according to a global survey by the World Economic Forum. It was released just before the foundation’s annual meeting of global leaders in Davos, Switzerland. The survey of nearly 1,000 international experts and decision makers reveals that in terms of likelihood and impact, extreme weather around the world is listed as the top concern. The survey points to how catastrophic hurricane damage and wildfires can devastate crucial infrastructure.
Collateral damage
Wildlife in more than 70 percent of Africa’s nature preserves was decimated by the ravages of war from 1946 to 2010, causing populations to enter what a new report describes as a “downward spiral.” Writing in Nature, scientists point to the deaths of 90 percent of the large herbivores in Mozambique’s Gorongosa National Park during that country’s decades-long struggle for liberation from Portugal.
Eruption
Long streams of lava flowing down the slopes of Mayon volcano in the Philippines prompted more than 34,000 people to flee. Plumes of ash fell on villages, threatening to contaminate crops and water supplies.
Warming demographics
One of the world’s largest sea turtle colonies is becoming almost entirely female because of a warming climate. Scientists from the United States and Australia write in Current Biology that sand temperatures determine the gender of turtle hatchlings. Because higher temperatures result in more females, virtually no male turtles are hatching on the hotter nesting beaches of Australia’s northern Great Barrier Reef.