gfs and global models
DESCRIPTION
GFS and Global Models. Global Forecast System (GFS) Model. Previous called the Aviation (AVN) and Medium Range Forecast (MRF) models. Spectral global model and 64 levels Relatively primitive microphysics. Sophisticated surface physics and radiation Run four times a day to 384 hr (16 days!). - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/1.jpg)
GFS and Global Models
![Page 2: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/2.jpg)
Global Forecast System (GFS) Model
• Previous called the Aviation (AVN) and Medium Range Forecast (MRF) models.
• Spectral global model and 64 levels• Relatively primitive microphysics.• Sophisticated surface physics and radiation• Run four times a day to 384 hr (16 days!).• Major increase in skill during past decades derived
from using direct satellite radiance in the 3DVAR analysis scheme and other satellite assets.
• T574 (~27 km) over the first 192 hours (8 days) of the model forecast and T190 (70 km) for 180 through 384 hours--major implications for resolution change!
![Page 3: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/3.jpg)
GFS
• Vertical coordinates are hybrid sigma/pressure… sigma at low levels to pressure aloft.
![Page 4: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/4.jpg)
Vertical coordinate comparison across North America
![Page 5: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/5.jpg)
GFS Data Assimilation (GDAS)• Has a later data cut-off time than the mesoscale
models…and thus can get a higher percentage of data.• Uses much more satellite assets..thus improve global
analysis and forecasts.• Major gains in southern hemisphere• Hybrid Data assimilation based on 3DVAR (they call
it GSI) and GFE ensemble (next slide)• Every 6 hr.
![Page 6: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/6.jpg)
GFS Hybrid Data Assimilation
![Page 7: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/7.jpg)
GFS is not the only global model and is not even the best
![Page 8: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/8.jpg)
![Page 9: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/9.jpg)
![Page 10: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/10.jpg)
![Page 11: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/11.jpg)
![Page 12: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/12.jpg)
![Page 13: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/13.jpg)
![Page 14: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/14.jpg)
Next Generation Global Models Under Development!
• Will use different geometries
![Page 15: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/15.jpg)
MPAS: Hexagonal Shapes
![Page 16: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/16.jpg)
![Page 17: GFS and Global Models](https://reader036.vdocuments.us/reader036/viewer/2022062321/56813266550346895d98ffe7/html5/thumbnails/17.jpg)
NOAA FIM Model