San Francisco Chronicle - (Sunday)
Earthweek: a diary of the planet
For the week ending Friday, April 1.
Early birds
A study finds that some birds in the U.S. Midwest are laying their eggs about a month earlier than they did a century ago, with the warming climate seen as the cause. Led by Chicago’s Field Museum, a team compared century-old eggs preserved in the museum’s unique collection with recent observations. Each egg is accompanied by a label, noting the kind of bird and where and when it was collected. A third of the 72 species studied around Chicago now lay their eggs about 25 days earlier than a century ago. The gradual shift to an earlier spring has large impacts, and scientists believe it is responsible for the steep decline in bird populations since the 1970s.
Blood plastic
Dutch researchers say that for the first time, microplastics have been found in human blood samples. Writing in Environment International, they document how a small study detected traces of the plastic pollutants in the blood samples of 17 out of 22 volunteers. The study suggests the PET plastic and polystyrene particles were probably inhaled or ingested before winding up in the bloodstream. The substances are found in plastic bottles, polyester fibers and other products. The researchers also emphasize that more studies are needed to determine whether the substances pose a public health risk.
Rumblings
Swarms of volcanic tremors in Portugal’s Azores archipelago have farmers and officials there worried that an eruption similar to Spain’s La Palma last year is imminent. The rumblings on lush São Jorge have already prompted the evacuation of some elderly and disabled residents near where the seismic activity has been centered. The last eruption there occurred in 1808. > More than 4,000 people were evacuated from around the Philippines’ Taal volcano as an eruption intensified.
Crypto energy
Bitcoin mining by huge arrays of servers around the world consumes an oversize amount of electricity as its network verifies secure transactions with extremely complex puzzles. It is estimated that the process already consumes as much energy as Sweden, and its drain on global power grids is growing. Greenpeace and other environmental groups say that a coding switch could greatly reduce Bitcoin’s energy consumption.
Reef bleaching
Aerial surveys of Australia’s Great Barrier Reef reveal that there is now so much new dead coral that scientists believe a serious coral bleaching event is developing. Rising ocean temperatures because of climate change are blamed for the more-frequent bleaching. But this bleaching event is occurring during a La Niña ocean-cooling event, which typically helps cool the reef. Experts say that climate change is now overpowering that process and leaving the reef under constant thermal stress.