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Dr Andrew Glikson, a Earth and paleoclimate scientist, is a Visiting Fellow at the School of Archaeology and Anthropology, Australian National University, where he is reviewing the effects of climate on prehistoric human evolution.

Another link between CO2 and mass extinctions of species

It’s has been know that massive increases in emission of CO2 from volcanoes, associated with the opening of the Atlantic Ocean in the end-Triassic Period, set off a shift in state of the climate which caused global mass extinction of species, eliminating about 34% of genera. The extinction created ecological niches which allowed the rise […] … learn more→

On tree rings, CO2 levels and the Pliocene

A study of tree-ring data recently found that in some regions temperatures during Roman times (21AD to 50AD) were 1.05 degrees Celsius higher than the 1951-1980 mean. The paper’s lead author, Professor Jan Esper of Johannes Gutenberg University in Mainz, Germany, and his colleagues wrote that: “large-scale near-surface air-temperature reconstructions relying on tree-ring data may […] … learn more→

James Lovelock’s climate change U-turn

Recent statements by James Lovelock, the distinguished physicist, are not easy to reconcile with his statements, writings and books over the years, including The Vanishing Face of Gaia; The Revenge of Gaia and others. As recently as March 30th, 2011, it was reported: “Professor James Lovelock, the scientist who developed Gaia theory, has said it […] … learn more→

The discovery of fire: initial steps toward anthropogenic climate change

The evidence for a rapid shift in state of the terrestrial atmosphere-ocean system over the last two centuries (see figure 1) requires a deep time perspective, beyond events of the day. Tracing the original blueprints of anthropogenic effects on the terrestrial environments takes us back at least a million years to the time when – […] … learn more→

On Arctic Sea ice melt and coal mine canaries

Despite peak global temperatures in 2005 and 2010 (unprecedented in the instrumental record), a recent sharp plunge in volume of the Arctic Sea ice and a spate of extreme weather events, coal mining, coal exports and carbon emissions continue to grow, overwhelming any mitigation attempted by schemes such as the Australian carbon price. And although […] … learn more→

Is another mass extinction event on the way?

Why have mass extinctions of species occurred since the late Proterozoic (from 580 million years ago) and repeatedly through the Phanerozoic? Integral to these extinctions were abrupt changes in the physical and chemical properties of the atmosphere, ocean and land, inducing environmental changes at a pace to which many species could not adapt. The best […] … learn more→

As emissions rise, we may be heading for an ice-free planet

Last December’s meeting of the American Geophysical Union featured three of the world’s leading climate scientists: James Hansen (NASA’s chief climate scientist), Elco Rohling (National Oceanography Centre, Southampton) and Ken Caldeira (Stanford School of Earth Science). But it was Hansen who attracted the most attention when he stated: “If you doubled CO₂, which practically all […] … learn more→

An Orwellian climate

“Everyone is entitled to his own opinions, but not to his own facts” – Australian Senator Daniel Moynihan Science is a systematic, evidence-based, testable and self-correcting way of investigating the world. This is done through empirical observation, by experimentation and mathematics. Ideologically dominated or totalitarian societies – such as George Orwell’s famous “1984” Ingsoc – […] … learn more→

When it comes to greenhouse gases carbon dioxide isn’t the only culprit

Most of the discussion about slowing the impact of climate change has focussed on reducing carbon dioxide emissions. But carbon dioxide isn’t the only greenhouse gas. Methane, halocarbons and nitric oxide are also important contributors to climate change. Are we taking the right steps to reduce these emissions? A new National Oceanic and Atmospheric Administration […] … learn more→