Archive by category | Palaeoclimate

Timeline: Ice memory

Some of scientists’ gravest concerns about future climate change are rooted in the past. Records studied by paleoclimatologists reveal that the more extreme possibilities for this century and beyond — temperatures soaring, ice sheets vanishing, fertile lands withering into deserts — were realized previously on Earth when atmospheric greenhouse gas levels surged. At this summer’s AGU Chapman Conference on Abrupt Climate Change, researchers described this turbulent history through all manner of proxies – ice, tree rings, corals, marine and lake sediments, among others. But few talks went without a slide showing the wiggly line of a deep ice core.  Read more

Unknown climate culprit for Palaeocene-Eocene warming

Unknown climate culprit for Palaeocene-Eocene warming

A reconstruction of the Earth’s climatic history during a key hot period 55 million years ago has highlighted a yawning gap in our understanding: this period’s rise in carbon dioxide accounts for just half of its warming. Some as-yet-unidentified climate feedbacks could be at work, the scientists behind the research conclude.  Read more

Interview: Lonnie Thompson

Interview: Lonnie Thompson

At the AGU Chapman Conference last month I met up with Lonnie Thompson, the alpine glaciologist who has spent more time above 20,000 feet than any other human. Despite being interrupted by last-minute demands from Peruvian customs officials – he was squeezing me in before taking off for a new expedition in the Andes – an unphased Thompson carefully laid out the past and present-day climate change that his work has uncovered. Here’s an extract: What information can you garner from glaciers? Glaciers are like sentinels, and they’re telling us that the system is changing. The first thing we look  … Read more

Holy snakes!

Holy snakes!

Posted on behalf of Roberta Kwok Scientists have found a new way to estimate past climate: snakes. In case you haven’t seen the media flurry, researchers have uncovered the remains of a gigantic snake in northeastern Colombia (which news outlets have described as “” http://features.csmonitor.com/discoveries/2009/02/04/prehistoric-one-ton-super-snake-ate-alligators-for-lunch">Super-snake", “”http://www.google.com/hostednews/afp/article/ALeqM5gvMX4MXQYzy22YM8gMEBTIUR6lFQ">Bus-sized boa", and “”http://www2.canada.com/technology/columnists/grandaddy+snake+world+unearthed+colombia/1252613/story.html?id=1252613">Granddaddy of the snake world", among other things). The newly named Titanoboa cerrejonensis would have measured 13 metres long and weighed about 1,135 kilograms, making it the biggest known snake, living or extinct. Why does this matter for climate predictions? The snake lived 58 to 60 million years ago, around the Palaeocene  … Read more