Professor Paul Wilson is Head of Palaeoceanography and Palaeoclimate Research Group, Professor within Ocean and Earth Science, National Oceanography Centre Southampton at the University of Southampton. Before moving to Southampton two decades ago he spent a decade at Cambridge where he undertook his PhD with Harry Elderfield. He has helped lead the international effort through scientific ocean drilling to acquire the archives needed to decrypting the climate record for diagenetic bias, ice volume and temperature.
Carbon dioxide, CO2, is a powerful greenhouse gas and humans have increased its concentration in Earth's atmosphere by around 35% since the start of the Industrial Revolution (in ca. 250 yrs) to a level that is higher than at any time in the past 800 thousand years as measured in air bubbles obtained from ice cores. If humans continue to emit CO2 to the atmosphere following projected rates, then by 2100, concentrations will reach values not seen since the Palaeogene epoch (ca. 65-23 million years ago, Ma) when Earth's climate was much warmer than today, featuring, for example, a genuinely green Greenland. These startling observations provide a powerful incentive to improve our understanding of the Palaeogene climate system.
In this seminar, I will discuss Earth’s transition from a warm largely deglaciated climate state in the early Paleogene to one in which it was cool enough to sustain large ice sheets, first on Antarctica and, then in the northern hemisphere. I will argue (i) that this pivot point in Earth’s climate history provides a startling example of a dramatic threshold response to slow forcing and (ii) that, once established, the early Antarctic ice sheet was more dynamic than is widely acknowledged.
Arranged date for the seminar talk: Dec 02, 2019 at 14:15
BCCR lecture room 4020, Jahnebakken 5