depthMeters: Depth in meters given a latitude and longitude point.

In John-R-Wallace-NOAA/Imap: Interactive Mapping

Depth in meters given a latitude and longitude point.

Description

depthMeters gives the depth, in meters, using data from NOAA NCEI's Grid Extraction. Note that, even though the SoCal 1 Arc-Second data extends to the southeastern corner of U.S. West Cost EEZ, the SoCal 3 Arc-Second coverage goes further south and west.

Usage

depthMeters(LongLat = c(-120, 33), layer = layer, plot = ifelse(N < 5, TRUE, FALSE), SoCal_1as = TRUE, 
     blockSizeDegs = ifelse(plot, ifelse(SoCal_1as, 0.5, 2), ifelse(SoCal_1as, 0.005, 0.002), method = "bilinear", 
      verbose = plot, quiet = !plot, Zero.to.NA = TRUE, plot3D = FALSE, GoogleEarth = FALSE, alphaGoog = 0.5)  

Arguments

LongLat	A single long/lat vector or a matrix or data frame with longitude in the first column and latitude in the second column.
layer	Which layer should be used: 'ETOPO1_ice_surface' = Entire Earth's surface with the top of the Antarctic and Greenland ice sheets depicted (1-minute resolution), 'ETOPO1_bedrock' = Entire Earth's surface with bedrock depcted on Antarctic and Greenland (1-minute resolution), 'crm' = Coastal Relief Model for the contiguous U.S. coastline (3 arc-second resolution), 'socal_3as' = Southern California (3 arc-second resolution), or 'socal_1as' = Southern California (1 arc-second resolution). The default is ETOPO1_ice_surface.
plot	Should a plot be created showing the bathmetry and the point at which the depth is extracted. Default is TRUE when the number of depths asked for is less than 5 and FALSE otherwise.
SoCal_1as	Should should a smaller bounding box be used when the longlat point is within the Southern Cali 1 Arc-Sec data. The default is TRUE.
blockSizeDegs	The block size, in degrees, over which the depth is extracted. The default when plotting is 0.5 degrees on a side for the 1 Arc-Second data covering southern California and 2 degrees otherwise. The default when not plotting is 0.005 degrees on a side for the 1 Arc-Second data covering southern California and 0.002 degrees otherwise.
method	Method used to extract the depth from a Raster object using the extract function in the raster package. Defaults to 'bilinear'.
verbose	Should information about the layer used be shown. Default is equal to the 'plot' augument.
quiet	Should addition information be surpressed. Defaults to the logical negation of the 'plot' augument.
Zero.to.NA	When a long/lat point is in a volume, but outside of an area which contains data, an exact zero is extracted. Should these zeros be converted into NA's. The default is TRUE.
plot3D	Plot a 3D cloud of color banded points using the 'rgl' package.
GoogleEarth	Show the raster image (converted to KML format) in Google Earth. The default is FALSE.
alphaGoog	Set the alpha transparency level for the raster image in Google Earth. The default is 0.5.

Value

The depth in meters of the point(s) given.

Author(s)

John R. Wallace: [e-mail]

References

For getting the bathymetry into R, I followed Tom Wainwright here: http://rstudio-pubs-static.s3.amazonaws.com/53530_1af2d0b5ae1f4a36a75e611d3566f777.html#1

U.S. Coastal Relief Model Map is here: http://www.ngdc.noaa.gov/mgg/coastal/crm.html

See Also

raster

Examples

## Not run: 

# Compare the difference in fine resolution when the block size is decreased. 
  depthMeters(c(-118.6439, 33.4808), blockSizeDegs = 0.5) 
  depthMeters(c(-118.6439, 33.4808), blockSizeDegs = 0.005)

# Look at the image in Google Earth
  depthMeters(c(-118.6439, 33.4808), blockSizeDegs = 0.005, Google = T)
  
# Here is an example of the where the long/lat point is in a volume but outside of the data area: 
  depthMeters(rbind(c(0, 0), c(-120, 33), c(-135, 41)), 0.01, Zero.to.NA = F)
  
# Example of using plot3D and Google Earth
  depthMeters(c(-118.229967, 32.1018333), 0.02, plot3D = T, Goog=T)
    
# A data frame or matrix can also be used with longitude in the first column and latitude in the second.
# If you give depthMeters() 5 or more locations the 'plot' argument's default is not to create a figure for each one but to only return back the depths.
  LongLat <- data.frame(Long = c(-118.6442, -118.5227, -119.4888, -119.84, -120.00), 
                       Lat =  c(33.4817, 33.3485, 33.9634, 33.94, 33.00))
  depthMeters(LongLat)

## End(Not run)

John-R-Wallace-NOAA/Imap documentation built on April 1, 2024, 8:31 p.m.