getRegion: Get polygons corresponding to regions

Description Usage Arguments Details Value References Examples

View source: R/misc.R

Description

Takes in a matrix and returns polygons representing contiguous regions in the matrix. Typically these regions are either where the ice concentration is above a certain level or where there is land.

Usage

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getRegion(dat, datType, level = NULL, myLandMat = landMat,
  myAllRegions = allRegions, useAll = FALSE, landInd = FALSE,
  xmn = -3850, xmx = 3750, ymn = -5350, ymx = 5850)

Arguments

dat

matrix of one of the allowed data types ("gfdl", "bootstrap", or "simple) (see details)

datType

string indicating the format of the data: either "gfdl", "bootstrap", or "simple" (see details)

level

concentration level of interest

myLandMat

binary matrix specifying land locations

myAllRegions

SpatialPolygons object specifying region that will be considered

useAll

boolean, if true indicates to use the full area (overrides myLandMat)

landInd

boolean, if true indicates that the region of interest is the land

xmn

min x (defaults to value for polar stereographic grid, -3850)

xmx

max x (defaults to value for polar stereographic grid, 3750)

ymn

min y (defaults to value for polar stereographic grid, -5350)

ymx

max y (defaults to value for polar stereographic grix, 5850)

Details

For datType = "simple" the values in the dat matrix are indicators of whether the grid box contains ice (1: ice-covered, 0: no ice, NA: land). If datType = "gfdl" or datType = "bootstrap", the values in the matrix correspond to the raw ice concentrations values observed or predicted (including indicators for missing data, land etc.). If datType = "gfdl", the predictions are formatted as in the CM2.5 Forecast-oriented Low-Ocean Resolution (FLOR) model produced by the National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory converted to a Polar Stereographic grid (Vecchi et al. 2014; Msadek et al. 2014).If datType = "bootstrap" the array values are formatted the same as the ice concentration values obtaned from the National Aeronautics and Space Administration (NASA) satellites Nimbus-7 SMMR and DMSP SSM/I-SSMIS and processed by the bootstrap algorithm.

Value

region of interest as a SpatialPolygons object

References

Bootstrap sea ice concentration: Comiso, J., 2017: Bootstrap sea ice concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS. version 3. Boulder, Colorado USA: NASA National Snow and Ice Data Center Distributed Active Archive Center

CM2.5 Forecast-oriented Low-Ocean Resolution (FLOR) model:Vecchi, Gabriel A., et al. "On the seasonal forecasting of regional tropical cyclone activity." Journal of Climate 27.21 (2014): 7994-8016.

Msadek, R., et al. "Importance of initial conditions in seasonal predictions of Arctic sea ice extent." Geophysical Research Letters 41.14 (2014): 5208-5215.

National Center for Atmospheric Research, 2017: Earth system grid at NCAR. https://www.earthsystemgrid.org/home.html.

Examples

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## Not run: 
obsExample <-  getRegion(dat = obsFeb2012, datType = "bootstrap", level = 15)
plot(land, col = 'grey', border = FALSE)
plot(obsExample, col = "lightblue", add = TRUE)

## End(Not run)

hdirector/IceCastV2 documentation built on Dec. 9, 2018, 12:27 a.m.