An international team of scientists has shown how much sea level would rise if Larsen C and George VI, two Antarctic ice shelves at risk of collapse, were to break up. While Larsen C has received much attention due to the break-away of a trillion-tonne iceberg from it last summer, its collapse would contribute only a few millimetres to sea-level rise. The break-up of the smaller George VI Ice Shelf would have a much larger impact. The research is published today in the European Geosciences Union journal The Cryosphere.

Recent, rapid warming in the Antarctic Peninsula is a threat to ice shelves in the region, with Larsen C and George VI considered to have the highest risk of collapse. Because these large ice platforms hold back inland glaciers, the ice carried by these glaciers can flow faster into the sea when the ice shelves collapse, which contributes to sea-level rise. The new study shows that a collapse of Larsen C would result in inland ice discharging about 4 mm to sea level, while the response of glaciers to George VI collapse could contribute over five times more to global sea levels, around 22 mm.

“These numbers, while not enormous in themselves, are only one part of a larger sea-level budget including loss from other glaciers around the world and from the Greenland, East and West Antarctic ice sheets. Taken together with these other sources, the impacts could be significant to island nations and coastal populations,” explains study-author Nicholas Barrand, a glaciologist at the University of Birmingham in the UK. He adds: “The Antarctic Peninsula may be seen as a bellwether for changes in the much larger East and West Antarctic ice sheets as climate warming extends south.”

When my colleague Professor Tom Gill at University of Texas at El Paso alerted me to a recent study noting that cargo ships may be creating more lightning, my first reaction was that I wasn’t surprised at all. Though this may be a surprising finding to many scientists and the public, I have been conducting research for over two decades on how cities affect rainfall, storms, and lightning. As I read the paper, it was apparent to me that some of the same physical processes were at play with the cargo ship — lightning relationships. So how does a cargo ship create lightning?

AUSTIN, Texas (Reuters) — Despite advances in predicting where hurricanes are heading, forecasters are still struggling to determine a crucial factor in deciding emergency measures and evacuations: their intensity.

With a better way to predict a storm’s power, or intensity, people on the ground will be more prepared in knowing whether a hurricane headed their way will cause devastating floods and winds that can uproot trees like Maria, which devastated Puerto Rico last year, or just shake branches and rattle windows.

“The fact that we have a much better understanding of where these storms are going to go is a great first step. We sort of have half the circle filled in, and we need to get that other half filled in, which is that intensity component,” said Steve Bowen, director and meteorologist for insurer Aon Benfield’s Impact Forecasting team.