spatial forecast methods inter-comparison project -- icp spring 2008 workshop ncar foothills...
DESCRIPTION
Main Objectives What can a forecaster learn from the results of each approach? –What are the pros and cons of each? –What user-specific needs are met?TRANSCRIPT
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Spatial Forecast MethodsInter-Comparison Project -- ICP
Spring 2008 WorkshopNCAR Foothills Laboratory
Boulder, Colorado
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Welcome !!
• Main objectives• Agenda• Subjective Evaluations• General (Topic-specific ) Discussion
Questions• Some other things to think about• Where do we go from here?
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Main Objectives
• What can a forecaster learn from the results of each approach?– What are the pros and cons of each?– What user-specific needs are met?
![Page 4: Spatial Forecast Methods Inter-Comparison Project -- ICP Spring 2008 Workshop NCAR Foothills Laboratory Boulder, Colorado](https://reader035.vdocuments.mx/reader035/viewer/2022070605/5a4d1af87f8b9ab0599825cc/html5/thumbnails/4.jpg)
General (topic) discussions
• How would one use results from each method?
• What information is given about scale?• Operational concerns?
– Summarizing multiple cases– Computational efficiency
• Uncertainty characterization
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General Questions cont.
• Ease of interpretation• Appropriate applications
– Variables (e.g., precipitation, humidity, winds)– Domains– What information is needed for them to work– Can they characterize different attributes, and how?– Diagnostic information?
• Comparison of cases– How do they discern good vs. bad?
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Focus on Fake Cases
• How do the methods handle the fake cases?
• Has anything been learned from the cases?
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Other things to contemplate
• Categories– Filter Methods
• Scale-decomposition methods• Fuzzy/Neighborhood methods
– Motion Methods• Features-based methods• Field Morphing methods
– Not so easy to categorize Methods• FQI, CA, Composite, others?
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Scale Questions• All methods can be run for different resolutions.• Filter Methods
– Scale-decomposition separates scale information– Fuzzy/Neighborhood do not separate scale information,
but do directly provide info on scales• Motion Methods
– Can information about scale be gleaned?– MODE uses quilt plots of threshold against convolution
radius. Similar to fuzzy.• Other Methods
– CA refers to numbers of clusters as “scale.”
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Filter vs. Motion
Filter compares F and O fields at different scales, k, in the manner of
Where G is a traditional score (e.g., rmse)B is a filter (smoothing or band pass)
Gk (BF (F),BO (O))
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Filter vs. Motion
Motion moves forecast field (or structures within the fields) in the manner:
Where s are coordinates in the domain of the image.
G(F(WF (s)),O(WO (s)))