Did a Greenland Asteroid Cause Abrupt Warming Last Ice Age?

We report the discovery of a large impact crater beneath Hiawatha Glacier in northwest Greenland. From airborne radar surveys, we identify a 31-kilometer-wide, circular bedrock depression beneath up to a kilometer of ice http://advances.sciencemag.org/content/4/11/eaar8173 Hiawatha Glacier https://en.wikipedia.org/wiki/Hiawatha_Glacier Sources Discovering a massive meteorite crater https://www.youtube.com/watch?v=hQ9maLsIcts Massive crater under Greenland’s ice points to climate-altering impact in the…

Scientist Explains Climate Ice Core Proxies (2017)

This talk by Lonnie G. Thompson, focuses on glaciers as recorders and early indicators of climate change. The ongoing widespread melting of high-elevation glaciers and ice caps, particularly in low to middle latitudes, provides strong evidence that a large scale, pervasive and in some cases, rapid change in Earth’s climate system is underway. On Thursday…

Ice cores what they reveal and how deniers distort the data

First posted in 2011, still popular on denialist blogs. Peter Sinclair explains:  A widely circulated piece of climate denial nonsense purports to use legitimate evidence from Greenland ice cores to debunk the record of global warming. Displaying temperature records out of context, and making the claim of legitimacy by citing the data, and it’s primary author,…

Last Time Carbon Dioxide Levels Were This High: 15 Million Years Ago

By analyzing the chemistry of bubbles of ancient air trapped in Antarctic ice, scientists have been able to determine the composition of Earth’s atmosphere going back as far as 800,000 years, and they have developed a good understanding of how carbon dioxide levels have varied in the atmosphere since that time. But there has been…

In Ancient Ice, Clues That Scientists Are Underestimating Future Sea Levels

By John Mahoney / Popsci: The skies do strange things at the NEEM camp, a remote ice-drilling and research facility on the northern Greenland ice sheet. Midnight sunshine. Low clouds of sparkling ice crystals known as “diamond dust.” But when rain fell instead of snow last summer, complete with a rainbow arcing over the camp,…

Richard Alley: The Biggest Control Knob: Carbon Dioxide in Earth’s Climate History

In 2009, climate scientist Richard Alley (Pennsylvania State University) held the talk, “The Biggest Control Knob: Carbon Dioxide in Earth’s Climate History” (Bjerknes Lecture), at the American Geophysical Union Fall Meeting. CO2 is, and has always been, the biggest climate control knob in the Earth’s history https://mind.ofdan.ca/co2-is-and-has-always-been-the-biggest-climate-control-knob-in-the-earths-history 2015 release by AGU https://youtu.be/3UVb–2-PBg