Comparison of the PaleoMIST 1.0 ice sheet margins, ice sheet and paleo-topography reconstruction with paleo sea level indicators As a supplement to “A new global ice sheet reconstruction for the past 80 000 years” by Evan J. Gowan, Xu Zhang, Sara Khosravi, Alessio Rovere, Paolo Stocchi, Anna L. C. Hughes, Richard Gyllencreutz, Jan Mangerud, John-Inge Svendsen & Gerrit Lohmann Evan James Gowan In this package, there are two reports, each of which have five model runs that are compared with the standard PaleoMIST 1.0 ice sheet margins, ice sheet and paleo-topography reconstruction. The first document (report1) shows a comparison of the response using a variety of lower mantle viscosity values. The second document (report2) compares the standard PaleoMIST 1.0 with one where the ice load has been linearly interpolated to 500 year time steps, the alternate reconstruction with an ice covered Hudson Bay, and three other commonly used Earth models. The sea level data, plus the scripts used generate the report, can be found on Github: https://github.com/evangowan/paleo_sea_level I have also included the explicitly calculated sea level for all the models displayed in these reports in a zip file called "calculated_sea_level.zip". You can place the files in the folder "latex/calculated_sea_level" after you download the Git repository. A summary of the two documents are below: ------------------------------------- report1 - lower mantle models.pdf ------------------------------------- In this report there is a detailed summary, including plots, of a worldwide compilation of paleo-sea level data, and six ice sheet-Earth models. In this particular report, we compare the standard version of PaleoMIST 1.0 (with 2500 year time steps and using a lower mantle viscosity of 4 × 10^22 Pa s), with five other Earth models with viscosity values ranging between 10^21 and 10^23 . When developing PaleoMIST 1.0, a variety of lower mantle viscosity values were tested, and it was found that a value approaching 10^23 Pa s provided the best trade-off between increasing the amount of ice in the center of the Laurentide Ice Sheet and fitting the sea level data. This ended up being true for the Eurasian ice sheets as well. PaleoMIST 1.0 was tuned to an Earth model with a viscosity of 4 × 10 22 Pa s, but the comparison shown in this document demonstrate that a slightly higher value of 10^23 Pa s provides an even better fit. ------------------------------------- report2 - several models.pdf ------------------------------------- In this report there is a detailed summary, including plots, of a worldwide compilation of paleo-sea level data, and six ice sheet-Earth models. In this particular report, we compare the standard version of PaleoMIST 1.0 (with 2500 year time steps and using a lower mantle viscosity of 4 × 10^22 Pa s), a 500 year interpolated version of it, the alternative version of PaleoMIST 1.0, with an ice covered Hudson Bay during MIS 3, plus the standard version of PaleoMIST 1.0 calculated using Earth models proposed by James et al. (2009) (i.e. for tectonically active areas), Peltier et al. (2015) and Lambeck et al. (2017). The purpose of the interpolated version is to show that using a more gradual change in the load (since SELEN uses a heaviside function to compute the loading) will reduce the sea level in previously glaciated areas. Which of the two different scenarios for MIS 3 is more likely cannot be discriminated with the available data. Comparing the standard version of PaleoMIST 1.0 with other Earth models utilized in other studies show that our chosen Earth model provides a better fit to the data in formerly glaciated areas. This is unsurprising, since the ice model was tuned to our chosen Earth model. --------- Version 1.1: In this version, I have recalibrated all of the data with the new IntCal20 curves. I have added a few new LGM sites. I have also restored some of the data that I conservatively set to be marine limiting due to large uncertainties back to being index points. --------- Version 1.2: This version includes an update of the Baltic Sea dataset, as well as data from the North Sea region in Europe.