Speaker: Colin Meyer
Colin will be presenting the paper "Dynamics of ice stream temporal variability: Modes, scales, and hysteresis"
Here are his thoughts on the paper:
"Ice from the interior of continental ice sheets such as Greenland or Antartica primarily drains through fast-flowing, localized features called ice streams. These ice streams are known to turn on and off, known as stagnating and activating. The variability in ice stream discharge from the Hudson Strait ice stream of the Laurentide Ice Sheet is likely mechanism behind Heinrich events, where quantities of 'ice-rafted debris' are observed in sediment cores from the North Atlantic and can be traced to Hudson Bay. Robel et al. (2013) builds on the work by MacAyeal (1993) for ice stream binge-purge models to predict ice stream variability and thereby the frequency of Heinrich events. The key advancement is that the model developed by Robel et al. (2013) predicts timescale for Heinrich events, on the order of 7000 years, whereas MacAyeal includes this as a parameter. In this ClimaTea discussion, I will give some background on the physics of ice streams, go through the ingredients to the model, mentioning some strengths and shortcomings along the way, and describe the climatic implications. I will forego discussion of the mathematical analysis of the dynamical system, although it is a fun and elegant treatment."