San Francisco Chronicle - (Sunday)
Earthweek: a diary of the planet
For the week ending Friday, May 12.
Melting fears
A development in Greenland may confirm concerns that scientists have underestimated the rate at which the world's ice sheets are melting because of global heating. Writing in the Proceedings of the National Academy of Sciences, glaciologist Eric Rignot says daily tides of increasingly warmer waters have eaten a large hole at the bottom of Petermann Glacier, one of Greenland's largest, in the past two years. This is accelerating the retreat of a key part of the ice floe. Rignot warns that should this happen around the rest of Greenland and the larger Antarctic ice sheet, the accelerated glacier loss could cause sea levels to rise twice as fast as previously projected.
Eruption
Guatemala's Volcán de Fuego (Fire Volcano) erupted with thick clouds of ash that rained down on nearby farms and towns southwest of Guatemala City. More than 1,000 residents from five communities were temporarily evacuated to emergency shelters. The 12,300-foot Fuego is one of the most active in Central America. A 2018 eruption killed 194 people and left 234 others missing.
Higher calling
Collateral damage
Tuberculosis, the infectious disease with the highest death toll worldwide, is surging in the conflict zones of Ukraine and Sudan because of a breakdown of health services. Lucica Ditiu, executive director of the Stop TB Partnership, says the conflicts are having “a huge impact” on efforts to combat the disease. Ukraine has the highest number of people infected with TB in the European region, as well as the highest number of patients with drug-resistant TB. The COVID-19 pandemic's lingering effects are also contributing to the more than 4,400 daily tuberculosis deaths.
Puerto Rico's coquí frogs are croaking at a higher pitch, which scientists say is because of global heating. Comparisons of recordings made of the frog's distinctive two-note call, “co-qui,” made over the past 23 years reveal the change in pitch, says UCLA researcher Peter Narins. It has long been known that the amphibians are sensitive to temperature and call at different pitches based on elevation and microclimate. Narins says the calls grew higher in pitch at every location studied during the period.
Loss of smell
Carbon emissions and climate change are behind a significant thinning of the Pacific's Dungeness crab population in recent years, and research finds the trend is mostly because of the crustaceans losing their sense of smell. Marine scientists from the University of Toronto Scarborough say ocean acidification brought on by the absorption of rising levels of carbon dioxide seems to be impacting the crabs' ability to smell food. The Dungeness appear to be “flicking” their antennae less to find food.