Scientists call for regulation to stop regional use of marine cloud brightening having negative impact elsewhere
A geoengineering technique designed to reduce high temperatures in California could inadvertently intensify heatwaves in Europe, according to a study that models the unintended consequences of regional tinkering with a changing climate. The paper shows that targeted interventions to lower temperature in one area for one season might bring temporary benefits to some populations, but this has to be set against potentially negative side-effects in other parts of the world and shifting degrees of effectiveness over time. The authors of the study said the findings were "scary" because the world has few or no regulations in place to prevent regional applications of the technique, marine cloud brightening, which involves spraying reflective aerosols (usually in the form of sea salt or sea spray) into stratocumulus clouds over the ocean to reflect more solar radiation back into space. Experts have said the paucity of controls means there is little to prevent individual countries, cities, companies or even wealthy individuals from trying to modify their local climates, even if it is to the detriment of people living elsewhere, potentially leading to competition and conflict over interventions. The recent sharp rise in global temperatures has prompted some research institutions and private organisations to engage in geoengineering research that used to be virtually taboo. In Australia, scientists have been trialling marine cloud brightening strategies for at least four years to try to cool the Great Barrier Reef and slow its bleaching. Earlier this year, scientists at the University of Washington sprayed sea-salt particles across the flight deck of a decommissioned aircraft carrier, the USS Hornet, docked in Alameda in San Francisco Bay. This experiment was halted by the local government to…