EPSS Colloquium - fall-2012

Sept. 27, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Bernard Hallet - University of Washington

Seminar Description coming soon.

Oct. 4, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Carl Steefel - Lawrence Berkely National Laboratory

Cosponsored by the Institute of Environment and Sustainability.

Oct. 11, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Sarah Aciego - University of Michigan

Cosponsored by the Institute of the Environment and Sustainability.

Oct. 18, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Anders Carlson - U. of Wisconsin/Oregon State U.

Cosponsored by the Institute of the Environment and Sustainability.

Oct. 25, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Dave McComas - Southwest Research Institute

Cosponsored by iPLEX.

Nov. 1, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Lorraine Lisiecki - UCSB

Cosponsored by the Center for Applied Statistics.

Nov. 8, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Frank Corsetti - USC

Seminar Description coming soon.

Nov. 15, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Sean Solomon - Lamont-Doherty Earth Observatory

Cosponsored by iPLEX.

Nov. 29, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Isabel Montanez - UC Davis

At the current rate of global C emissions and without substantial mitigation efforts, atmospheric CO2 is projected to increase by the end of this century to levels not previously experienced on Earth since the onset of our current glacial state. Although Earth has been an icehouse for the past 34 million years, warmer greenhouse conditions have been the ‘typical’ climate state of the past half billion years. Unique insight into how the Earth system will function in such an evolving and high CO2 environment resides in the deep-time analogs of past climate and ecosystem response to greenhouse gas-forced warming of the magnitude comparable to that which we may ultimately face. The deep-time archive, a fully integrated record of climate-ecosystem interactions and feedbacks prompted by high levels of radiative forcing, reveals climate change in the past that was at times far more dynamic than suggested by reconstructions of the past few hundred thousand years. And records of past abrupt change reveal the much slower pace of naturally forced periods of global warming. The association of these periods with critical climate and ecological thresholds provides a context for the future. The inability of numeric climate models to reconstruct surface environmental conditions of past warm periods suggested by proxy records highlights the existence of fundamental processes in the climate system that require further evaluation, and which might indicate that climate projections for our future may well be underestimated. This presentation will discuss – in the context of projected atmospheric CO2 levels - examples of past major transitions that illustrate how greenhouse-gas forced climate change has unfolded in the past and that characterize the fingerprints of climate and ecological thresholds.

Dec. 6, 2012
4 p.m. - 5 p.m.
Geology 3656

Presented By:

• Yakov Galperin -

On 20 April 2010, while drilling at the Macondo Prospect, situated at the Mississippi Canyon block 252 (MC252), an explosion on the Deepwater Horizon rig caused by a blowout killed 11 crewmen and ignited a fireball visible from 35 miles (56 km) away. Two days later, the rig sank, leaving the well gushing at the seabed and causing the largest offshore oil spill in U.S. history: some 5,000,000 bbl (210,000,000 gal) released into the Gulf of Mexico. The setting of the spill is quite different from other historic marine oil spills that occurred at or near the sea surface. The Deepwater hydrocarbons were released at a depth of ~1,500 m (water pressure ~160 atm) in a high pressure jet (~500 atm), resulting in gas bubbles and liquid oil droplets of different size. Size and chemical composition of the hydrocarbon bubbles and droplets evolved extremely rapidly following release from the well. A complex interplay of physical and biochemical processes determined hydrocarbon-water plume mixing dynamics and affected the composition and spatial distribution of the hydrocarbon mixtures within the water column, at the surface in the resulting oil slick, and in the overlying atmosphere. This presentation considers impact of multiple sources of oil contamination and evaluates the role of different oil weathering processes that change the chemical composition of oil in deep water and their effect on the long-term fate of oil in the Gulf of Mexico coastal waters.