Quantitative Precipitation Forecasting. The State Climatologist, Peter Olsson, is the lunch speaker.
1. Water Vapor
2. Cooling of the Atmosphere
Lifting agents - Large - warm front; Small - mountains
Cloud microphysics - cloud droplets to raindrops (2000 microns) - We don't really know what happens in the cloud. Can't do in a cloud chamber. Numerical models - scale from micron to thousands of kilometers.
Disclaimer #1: Gridded finite models and Spectral models
#2: differences between models used to be huge. Not so much any more.
Model Grids - [I'm not quite close enough to read the slides from my table near the electric outlet]
Global Climate models
Regional climate model
High resolution forecast model
Now he's talking about Orographic Precipitation - Compared to Girdwood, we have a 5:1 difference. Which side of the mountain you're on.
Orographic precipitation, also known as relief precipitation, is precipitation generated by a forced upward movement of air upon encountering a physiographic upland (see anabatic wind). This lifting can be caused by two mechanisms:He went through various technical problems in predicting.
1. The upward deflection of large scale horizontal flow by the orography.
Mountains play significant role in precipitation and we have lots of mountains. We tend to under predict in the winter and overpredict in summer. QPF is not a cookbook for predictions near the mountains.
How does this affect climate models? A lot more guesswork going into what they have to do.
I simply can't capture all he's saying. You probably need to contact him if you want the details.