Tornado characteristics and mapping are fundamentally a GIS based field of work due to heavy reliance on “geographic space” to map out tornado densities (Deng, Wallace, & Maasseen, 2016, p. 284). Because of this GIS influence, Deng et. al worked to provide a definition of tornadoes in GIS terms. They essentially outlined three facets of such definition arguing that a tornado is:
- “Dynamic event in space-time”
- “Truly three-dimensional in geographic space”
- “Has its own geometric, thematic, and temporal properties” (p. 284)
In order to identify tornadoes and their density, an area must be specified. The “adjustment of the area in shape and size” alters the “density reading” (p.284) of tornadoes for the locations. The image below depicts tornado densities of the Eastern United States at 12 variations of neighborhood scales “ranging from 20-360 km” (p. 294). The distance decay function used in this analysis affects the amount of “smoothing” of the projection. The bigger the distance is between sites chosen, the more amount of smoothing occurs affecting the interpretation of each map.
The overall argument to the work of Deng et al. is that tornado density models are “relative” and the models depend on the “neighborhood size, the choice of the distance decay function, and the involved tornado properties” (p.294). Understanding the methodology behind certain maps and GIS information allows for higher understanding of the subject, decreases potential false readings, and allows for alterations in maps using the same data to be comprehended.
Deng, Y., Wallace, B., Maassen, D., & Werner, J. (2016). A Few GIS Clarifications on Tornado Density Mapping. Journal Of Applied Meteorology & Climatology, 55(2), 283-296. doi:10.1175/JAMC-D-15-0141.1
I have acted with honesty and integrity in producing this work, and am unaware of anyone who has not - Hailey Johnson
These maps are helpful for new home buyers to keep in mind when deciding where to move to. I wonder if the same program would be capable of producing a frequency map of higher density tornadoes?
ReplyDeleteThese maps are helpful for new home buyers to keep in mind when deciding where to move to. I wonder if the same program would be capable of producing a frequency map of higher density tornadoes?
ReplyDeleteThis article discusses an important point- that maps are only as accurate as the data used. It's interesting to see how the larger-scale maps "smooth-out" the patterns while the smaller scale maps shows little hot spots.
ReplyDeleteThis article discusses an important point- that maps are only as accurate as the data used. It's interesting to see how the larger-scale maps "smooth-out" the patterns while the smaller scale maps shows little hot spots.
ReplyDelete