scworland / restore-2018

scripts for predicting streamflow characteristics in ungaged basins for RESTORE
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Projection System (Alber's Central Meridian) #14

Closed ghost closed 6 years ago

ghost commented 6 years ago

The Alber Equal Area project system (https://en.wikipedia.org/wiki/Albers_projection) is common in USGS maps of course. Below is a standard for North America. The latitude of origin and the parallels are good enough. Our study area shown below with the -96 central meridian.

ALBEA <- paste0("+proj=aea +lat_1=29.5 +lat_2=45.5 +lat_0=23 +lon_0=-96 ", "+x_0=0 +y_0=0 +datum=NAD83 +units=m +no_defs +ellps=GRS80 +towgs84=0,0,0") ALBEA <- sp::CRS(ALBEA)

screen shot 2018-01-08 at 7 35 34 am

But our study area is asymmetric to -96 longitude, perhaps -89 longitude is better as some of the perceived rotation is removed.

screen shot 2018-01-08 at 7 35 47 am

What are your thoughts? At the end of the day, I guess it does not much matter. It is trivial to transform of course, but the complication if we ever use a soap film smoother is that it is a sort of pain to get the polygon boundary prepared as library(mgcv) needs it.