About this person
Pilskog works on the biochemical component of the Norwegian earth system model, NorESM. His working on implementing Newton-Krylov methods to find the equilibrium state of carbon and other tracers in the oceans.
Earth system models, often called climate models, are so-called spin-up models. This means that we do not start out with a given climate, but a model for the physical and chemical processes that governs the tracers. Before we can conduct theoretical experiments on the climate, we need to let the system reach an equilibrium. This is reached when the system goes into predictive cycles with a given period. The time it takes to reach such an equilibrium is called the spin-up time and are measured in simulated years. Each simulated year carries a significant computational cost. The fast processes we can observe in the atmosphere and the upper layers of the ocean may take tens of simulated years, but if we include the abyss, we often need several thousand simulated years.
The spin-up time is necessary to obtain trustworthy results for our simulations, and it will be a huge advantage if it can be reduced. Traditionally the equilibrium state is found by direct time integration. The part of the ORGANIC project that Pilskog works on is trying to implement matrix free Newton-Krylov methods to estimate the equilibrium state. We hope to speed up the spin-up by a factor of two to ten. This might sound a little, but it will save days of calculations on some of the most powerful supercomputers in the world.
The researcher's background:
Pilskog defended his co-tutelle PhD the autumn of 2011. He was created PhD in physical chemistry from Université Pierre et Marie Curie (Paris 6) and PhD in theoretical atomic physics from the University of Bergen. The following half a year Pilskog was a Marie Curie fellow at the Centro Atomico, San Carlos de Bariloche, Argentina. From January 2013 until December 2015, Pilskog had a postdoctoral fellowship at Norwegian Academy of Science and Letters with support from VISTA, a collaboration between the Norwegian Academy of Science and Letters and Statoil. VISTA's overall vision is to stimulate basic mathematical and scientific research related to the exploitation and management of Norway's petroleum resources. Pilskog was working at the Department of Earth Science, UoB, during the fellowship. Pilskog started as postdoctoral fellow at Uni Research Climate January 2016.