 Okay, so continuing where I left off, so we've come with these settings, with these assumptions we've come pretty close to 550 ppm stabilization. If we look at the carbon emissions we can see that in fact to achieve that CO2 trajectory, that roughly 550 ppm CO2 trajectory stabilization, CO2 trajectory. We would need to bring emissions to a peak of less than 8 gigatons per year by the next decade or so and we would need to begin bringing them down. And in fact, if we had sought to stabilize CO2 concentrations at an even lower level, say 450 ppm, that's the blue curve here, which we're well above, to stabilize CO2 concentrations at 450 ppm, we would need to bring emissions to a peak even sooner and we would need to start bringing them down far more quickly in future decades. And so for your first course project described later on in this lesson, you are going to be playing around with the settings, the various assumptions for per capita economic growth, energy intensity and carbon efficiency projections for the future and perhaps population assumptions about population growth and population stabilization and see if you can come up with a realistic scenario, a justifiable scenario of assumptions for these various terms that allow us to stabilize CO2 concentrations at a level that would minimize the risk of exceeding what we might define as dangerous human interference with our climate. So your first project will involve integrating what we've learned about climate models using simple climate models to look at projected temperature increases and then looking at the distribution, the probability of future temperature increases and what changes we could make in policy and behavior that would allow us to stabilize CO2 concentrations at a level that gives us a fairly high probability of avoiding breaching some temperature, some warming limit that we might define as dangerous interference with the climate. So you'll have lots of time to play around with this and get used to using this tool yourself and combining it with projections that we make from our simple energy balance model to address these issues in your first project.