Compare 2007 and 2012 lake condition

library(nlaR)

library(sf)
library(maps)

par(mfrow = c(1, 2))

dt <- nla_load(2007)

dt <- st_as_sf(dt$SampledLakeInformation, coords = c("LON_DD", "LAT_DD"), crs = 4326)

map("usa")
plot(dt['URBAN'], add = TRUE, reset = FALSE)
title("NLA 2007")

dt <- nla_load(2012)
dt <- st_as_sf(dt$wide_siteinfo, coords = c("LON_DD83", "LAT_DD83"), crs = 4326)

map("usa")
plot(dt['URBAN'], add = TRUE, reset = FALSE)
title("NLA 2012")