How to look up timezones for 8,000 locations in R

If you have ever worked with dates and times over a wide geographical area, you will know that timezone math is tedious but important. In the forthcoming update of the rclimateca package, the list of climate locations provided in the package will contain the UTC offsets for what Environment Canada calls “local standard time”. Because the UTC offset for local standard time at each location is not provided with the list of locations from Environment Canada, I had to use the latitude and longitude of each site to obtain this information.