Earthweek: a diary of the planet

For the week ending Friday, May 19.

Urban cloudiness

New analysis of satellite data reveals that clouds form more often above cities and their suburbs than in surrounding rural landscapes, especially at night and during summer. Writing in the Proceedings of the National Academy of Sciences, researchers say they found that skies above urban areas, regardless of their size, saw 3% to 6% more cloud cover than in the countryside. They believe that because summer nights are generally warmer in cities because of the urban heat island effect, that warmth pulls up moisture from the landscape, creating the clouds. The effect disappears or is lessened during winter.

Popo eruption

Relentless heating

Experts warn that the world will probably heat above the 1.5 degree Celsius aspirational limit by 2027, which the U.N. weather agency says would bring dire consequences should it be permanently breached. While that target is likely to be exceeded only briefly, it would represent a marked acceleration of human impacts on the global climate system and send the world into “uncharted territory,” according to the World Meteorological Organization. The surge in global heating will be in part because of a strong El Niño ocean warming already beginning to develop across the surface of the tropical Pacific.

Mexico’s restive Popocatépetl volcano produced a sharp increase in activity, spewing fountains of hot lava high into the sky southeast of Mexico City. Ash from a series of more than 200 blasts also fell on nearby communities, including the city of Puebla.

Locust invasion

Northern Afghanistan’s breadbasket is being carpeted by a new generation of Moroccan locusts, which the U.N. Food and Agriculture Organization says could ravage the region’s crops should they mature. Villagers and farmers have been collecting the young “hoppers” and killing them before they can fly and swarm across the land. “You kill millions of locusts that way. The problem is there are billions of locusts,” said FAO representative Richard Trenchard. An invasion of Moroccan locusts in 1981 wiped about a quarter of Afghanistan’s national harvest.

Tropical cyclones

Scores of people died when Super Cyclone Mocha slammed into Myanmar’s northern Bay of Bengal coast. The storm weakened slightly just before inflicting destruction on coastal communities and parts of neighboring Bangladesh. Cyclone Fabien briefly passed to the southeast of the Chagos Archipelago.

City ‘forests’

A leading Japanese beverage company announced an audacious plan to cut its overall carbon emissions by placing vending machines across the country that can “absorb carbon dioxide.” Asahi Group Holdings plans to begin testing them to prove they can suck in CO from the air while they warm or cool drinks for thirsty customers. The firm is dubbing the network of machines “forests in the city,” referring to trees’ ability to absorb the greenhouse gas. The vending units will have a white powder inside that can absorb CO2, which will then be used for industrial purposes such as making fertilizer and food for algal seabeds.