2008 simulation
Here:
is a link to a video of the surface temperature during the 2008 season. This is more of a test than anything else.
jay-
April 21, 2009
April 2, 2009
model sensitivity result
Here's an early model sensitivity result from a series of runs I just did. I tested the model's sensitivity to two parameters:
1. The initial starting temperature: The base case has a uniform initial temperature of 3.8C, and I did two runs where everything else is identical, but I use an initial temperature of 2.8C or 4.8C. These are HUGE swings in initial heat content, but not completely unrealistic, based on observational data.
2. The air temperature. For the base case, I use a forcing field of AT, then I did two runs where I added and subtracted 1C.
I present the results in two different fashions:
1. Heat content, scaled to average temperature
2. Surface temperature at the location of the western NOAA buoy.
here are the results:
The first row shows the case where I start with a different initial condition. What I'm really interested in here is, since they are all being forced identically, they should all eventually approach the same solution. Here we can see that after a year, they are still separated by ~0.1C or so. Most of the difference goes away in the fall cooling period at the end of the year- much of the difference is retained through the winter and much of the summer. It also clearly makes a huge impact on the date of summer overturn.
In the case where I start with an identical initial condition but vary the air temperature by +/- 1C, there is remarkably little difference, but it has just occurred to me that I may not have done these right. For now, ignore the bottom row.
jay-
March 19, 2009
Early model-mooring comparison
Okay, just for fun I've plotted moored data (from the Werne/Austin mooring in Western Superior) and temperature data from the model ,at the nearest equivalent grid point. Remember that we only have mooring data available through the end of September , when we last visited the mooring. Take a look:
A few quick comments:
It's not bad, for a first cut. The model does a good job of producing winter stratification. It fails to mix away stratification in the spring, which occurs at the mooring. The model does a good job of predicting the timing of the onset of summer stratification. The model heats up a little more slowly than the observations, though both predict a maximum surface temperature of around 18C, though the timing is slightly different. there's an intense mixing event in late August which is followed by seiching activity (in general, the model results are a bit more seiche-y than the observations). The deep water in both cases is very close to Tmd.
It will be interesting to recover the mooring this spring and see how the fall data plays out.
jay-
Ice run with adjusted humidity
Not sure how this will work- I got it to run with Real Player, but didn't work with the Windows media player.