Selecting time intervals in raster

This example shows how to select data for a specific time period

First, let’s read a geospatial raster dataset

library(raster)
dat = stack("../../Data/CMIP6/MIROC6/MIROC6_tas_historical.nc")

Let’s take a look at the raster header

print(dat)

## class      : RasterStack 
## dimensions : 128, 256, 32768, 432  (nrow, ncol, ncell, nlayers)
## resolution : 1.40625, 1.400437  (x, y)
## extent     : -0.703125, 359.2969, -89.62795, 89.62795  (xmin, xmax, ymin, ymax)
## crs        : +proj=longlat +datum=WGS84 +no_defs 
## names      : X1979.01.16, X1979.02.15, X1979.03.16, X1979.04.16, X1979.05.16, X1979.06.16, X1979.07.16, X1979.08.16, X1979.09.16, X1979.10.16, X1979.11.16, X1979.12.16, X1980.01.16, X1980.02.15, X1980.03.16, ...

The raster “dat” has 432 layers. Each layer corresponds to month starting on 1979-01-16

You can also get a raster’s layers with the function ‘names()’

print(names(dat))

##   [1] "X1979.01.16" "X1979.02.15" "X1979.03.16" "X1979.04.16" "X1979.05.16"
##   [6] "X1979.06.16" "X1979.07.16" "X1979.08.16" "X1979.09.16" "X1979.10.16"
##  [11] "X1979.11.16" "X1979.12.16" "X1980.01.16" "X1980.02.15" "X1980.03.16"
##  [16] "X1980.04.16" "X1980.05.16" "X1980.06.16" "X1980.07.16" "X1980.08.16"
##  [21] "X1980.09.16" "X1980.10.16" "X1980.11.16" "X1980.12.16" "X1981.01.16"
##  [26] "X1981.02.15" "X1981.03.16" "X1981.04.16" "X1981.05.16" "X1981.06.16"
##  [31] "X1981.07.16" "X1981.08.16" "X1981.09.16" "X1981.10.16" "X1981.11.16"
##  [36] "X1981.12.16" "X1982.01.16" "X1982.02.15" "X1982.03.16" "X1982.04.16"
##  [41] "X1982.05.16" "X1982.06.16" "X1982.07.16" "X1982.08.16" "X1982.09.16"
##  [46] "X1982.10.16" "X1982.11.16" "X1982.12.16" "X1983.01.16" "X1983.02.15"
##  [51] "X1983.03.16" "X1983.04.16" "X1983.05.16" "X1983.06.16" "X1983.07.16"
##  [56] "X1983.08.16" "X1983.09.16" "X1983.10.16" "X1983.11.16" "X1983.12.16"
##  [61] "X1984.01.16" "X1984.02.15" "X1984.03.16" "X1984.04.16" "X1984.05.16"
##  [66] "X1984.06.16" "X1984.07.16" "X1984.08.16" "X1984.09.16" "X1984.10.16"
##  [71] "X1984.11.16" "X1984.12.16" "X1985.01.16" "X1985.02.15" "X1985.03.16"
##  [76] "X1985.04.16" "X1985.05.16" "X1985.06.16" "X1985.07.16" "X1985.08.16"
##  [81] "X1985.09.16" "X1985.10.16" "X1985.11.16" "X1985.12.16" "X1986.01.16"
##  [86] "X1986.02.15" "X1986.03.16" "X1986.04.16" "X1986.05.16" "X1986.06.16"
##  [91] "X1986.07.16" "X1986.08.16" "X1986.09.16" "X1986.10.16" "X1986.11.16"
##  [96] "X1986.12.16" "X1987.01.16" "X1987.02.15" "X1987.03.16" "X1987.04.16"
## [101] "X1987.05.16" "X1987.06.16" "X1987.07.16" "X1987.08.16" "X1987.09.16"
## [106] "X1987.10.16" "X1987.11.16" "X1987.12.16" "X1988.01.16" "X1988.02.15"
## [111] "X1988.03.16" "X1988.04.16" "X1988.05.16" "X1988.06.16" "X1988.07.16"
## [116] "X1988.08.16" "X1988.09.16" "X1988.10.16" "X1988.11.16" "X1988.12.16"
## [121] "X1989.01.16" "X1989.02.15" "X1989.03.16" "X1989.04.16" "X1989.05.16"
## [126] "X1989.06.16" "X1989.07.16" "X1989.08.16" "X1989.09.16" "X1989.10.16"
## [131] "X1989.11.16" "X1989.12.16" "X1990.01.16" "X1990.02.15" "X1990.03.16"
## [136] "X1990.04.16" "X1990.05.16" "X1990.06.16" "X1990.07.16" "X1990.08.16"
## [141] "X1990.09.16" "X1990.10.16" "X1990.11.16" "X1990.12.16" "X1991.01.16"
## [146] "X1991.02.15" "X1991.03.16" "X1991.04.16" "X1991.05.16" "X1991.06.16"
## [151] "X1991.07.16" "X1991.08.16" "X1991.09.16" "X1991.10.16" "X1991.11.16"
## [156] "X1991.12.16" "X1992.01.16" "X1992.02.15" "X1992.03.16" "X1992.04.16"
## [161] "X1992.05.16" "X1992.06.16" "X1992.07.16" "X1992.08.16" "X1992.09.16"
## [166] "X1992.10.16" "X1992.11.16" "X1992.12.16" "X1993.01.16" "X1993.02.15"
## [171] "X1993.03.16" "X1993.04.16" "X1993.05.16" "X1993.06.16" "X1993.07.16"
## [176] "X1993.08.16" "X1993.09.16" "X1993.10.16" "X1993.11.16" "X1993.12.16"
## [181] "X1994.01.16" "X1994.02.15" "X1994.03.16" "X1994.04.16" "X1994.05.16"
## [186] "X1994.06.16" "X1994.07.16" "X1994.08.16" "X1994.09.16" "X1994.10.16"
## [191] "X1994.11.16" "X1994.12.16" "X1995.01.16" "X1995.02.15" "X1995.03.16"
## [196] "X1995.04.16" "X1995.05.16" "X1995.06.16" "X1995.07.16" "X1995.08.16"
## [201] "X1995.09.16" "X1995.10.16" "X1995.11.16" "X1995.12.16" "X1996.01.16"
## [206] "X1996.02.15" "X1996.03.16" "X1996.04.16" "X1996.05.16" "X1996.06.16"
## [211] "X1996.07.16" "X1996.08.16" "X1996.09.16" "X1996.10.16" "X1996.11.16"
## [216] "X1996.12.16" "X1997.01.16" "X1997.02.15" "X1997.03.16" "X1997.04.16"
## [221] "X1997.05.16" "X1997.06.16" "X1997.07.16" "X1997.08.16" "X1997.09.16"
## [226] "X1997.10.16" "X1997.11.16" "X1997.12.16" "X1998.01.16" "X1998.02.15"
## [231] "X1998.03.16" "X1998.04.16" "X1998.05.16" "X1998.06.16" "X1998.07.16"
## [236] "X1998.08.16" "X1998.09.16" "X1998.10.16" "X1998.11.16" "X1998.12.16"
## [241] "X1999.01.16" "X1999.02.15" "X1999.03.16" "X1999.04.16" "X1999.05.16"
## [246] "X1999.06.16" "X1999.07.16" "X1999.08.16" "X1999.09.16" "X1999.10.16"
## [251] "X1999.11.16" "X1999.12.16" "X2000.01.16" "X2000.02.15" "X2000.03.16"
## [256] "X2000.04.16" "X2000.05.16" "X2000.06.16" "X2000.07.16" "X2000.08.16"
## [261] "X2000.09.16" "X2000.10.16" "X2000.11.16" "X2000.12.16" "X2001.01.16"
## [266] "X2001.02.15" "X2001.03.16" "X2001.04.16" "X2001.05.16" "X2001.06.16"
## [271] "X2001.07.16" "X2001.08.16" "X2001.09.16" "X2001.10.16" "X2001.11.16"
## [276] "X2001.12.16" "X2002.01.16" "X2002.02.15" "X2002.03.16" "X2002.04.16"
## [281] "X2002.05.16" "X2002.06.16" "X2002.07.16" "X2002.08.16" "X2002.09.16"
## [286] "X2002.10.16" "X2002.11.16" "X2002.12.16" "X2003.01.16" "X2003.02.15"
## [291] "X2003.03.16" "X2003.04.16" "X2003.05.16" "X2003.06.16" "X2003.07.16"
## [296] "X2003.08.16" "X2003.09.16" "X2003.10.16" "X2003.11.16" "X2003.12.16"
## [301] "X2004.01.16" "X2004.02.15" "X2004.03.16" "X2004.04.16" "X2004.05.16"
## [306] "X2004.06.16" "X2004.07.16" "X2004.08.16" "X2004.09.16" "X2004.10.16"
## [311] "X2004.11.16" "X2004.12.16" "X2005.01.16" "X2005.02.15" "X2005.03.16"
## [316] "X2005.04.16" "X2005.05.16" "X2005.06.16" "X2005.07.16" "X2005.08.16"
## [321] "X2005.09.16" "X2005.10.16" "X2005.11.16" "X2005.12.16" "X2006.01.16"
## [326] "X2006.02.15" "X2006.03.16" "X2006.04.16" "X2006.05.16" "X2006.06.16"
## [331] "X2006.07.16" "X2006.08.16" "X2006.09.16" "X2006.10.16" "X2006.11.16"
## [336] "X2006.12.16" "X2007.01.16" "X2007.02.15" "X2007.03.16" "X2007.04.16"
## [341] "X2007.05.16" "X2007.06.16" "X2007.07.16" "X2007.08.16" "X2007.09.16"
## [346] "X2007.10.16" "X2007.11.16" "X2007.12.16" "X2008.01.16" "X2008.02.15"
## [351] "X2008.03.16" "X2008.04.16" "X2008.05.16" "X2008.06.16" "X2008.07.16"
## [356] "X2008.08.16" "X2008.09.16" "X2008.10.16" "X2008.11.16" "X2008.12.16"
## [361] "X2009.01.16" "X2009.02.15" "X2009.03.16" "X2009.04.16" "X2009.05.16"
## [366] "X2009.06.16" "X2009.07.16" "X2009.08.16" "X2009.09.16" "X2009.10.16"
## [371] "X2009.11.16" "X2009.12.16" "X2010.01.16" "X2010.02.15" "X2010.03.16"
## [376] "X2010.04.16" "X2010.05.16" "X2010.06.16" "X2010.07.16" "X2010.08.16"
## [381] "X2010.09.16" "X2010.10.16" "X2010.11.16" "X2010.12.16" "X2011.01.16"
## [386] "X2011.02.15" "X2011.03.16" "X2011.04.16" "X2011.05.16" "X2011.06.16"
## [391] "X2011.07.16" "X2011.08.16" "X2011.09.16" "X2011.10.16" "X2011.11.16"
## [396] "X2011.12.16" "X2012.01.16" "X2012.02.15" "X2012.03.16" "X2012.04.16"
## [401] "X2012.05.16" "X2012.06.16" "X2012.07.16" "X2012.08.16" "X2012.09.16"
## [406] "X2012.10.16" "X2012.11.16" "X2012.12.16" "X2013.01.16" "X2013.02.15"
## [411] "X2013.03.16" "X2013.04.16" "X2013.05.16" "X2013.06.16" "X2013.07.16"
## [416] "X2013.08.16" "X2013.09.16" "X2013.10.16" "X2013.11.16" "X2013.12.16"
## [421] "X2014.01.16" "X2014.02.15" "X2014.03.16" "X2014.04.16" "X2014.05.16"
## [426] "X2014.06.16" "X2014.07.16" "X2014.08.16" "X2014.09.16" "X2014.10.16"
## [431] "X2014.11.16" "X2014.12.16"

There are 432 layers, one for each month from 1979-01-16 to 2014-12-16

Let’s say that you want to select the interval between 1980-2014. In other words, you want to delete the first 12 months of data.

You can easily do this with the command below

dat_new = dat[[13:432]]

This is telling R to select layers 13 to 432 and save the result as a new raster called dat_new

print(dat_new)

## class      : RasterStack 
## dimensions : 128, 256, 32768, 420  (nrow, ncol, ncell, nlayers)
## resolution : 1.40625, 1.400437  (x, y)
## extent     : -0.703125, 359.2969, -89.62795, 89.62795  (xmin, xmax, ymin, ymax)
## crs        : +proj=longlat +datum=WGS84 +no_defs 
## names      : X1980.01.16, X1980.02.15, X1980.03.16, X1980.04.16, X1980.05.16, X1980.06.16, X1980.07.16, X1980.08.16, X1980.09.16, X1980.10.16, X1980.11.16, X1980.12.16, X1981.01.16, X1981.02.15, X1981.03.16, ...

The new raster “dat_new” has 420 layers, starting at 1980-01-16 and ending at 2014-01-16.

print(names(dat_new))

##   [1] "X1980.01.16" "X1980.02.15" "X1980.03.16" "X1980.04.16" "X1980.05.16"
##   [6] "X1980.06.16" "X1980.07.16" "X1980.08.16" "X1980.09.16" "X1980.10.16"
##  [11] "X1980.11.16" "X1980.12.16" "X1981.01.16" "X1981.02.15" "X1981.03.16"
##  [16] "X1981.04.16" "X1981.05.16" "X1981.06.16" "X1981.07.16" "X1981.08.16"
##  [21] "X1981.09.16" "X1981.10.16" "X1981.11.16" "X1981.12.16" "X1982.01.16"
##  [26] "X1982.02.15" "X1982.03.16" "X1982.04.16" "X1982.05.16" "X1982.06.16"
##  [31] "X1982.07.16" "X1982.08.16" "X1982.09.16" "X1982.10.16" "X1982.11.16"
##  [36] "X1982.12.16" "X1983.01.16" "X1983.02.15" "X1983.03.16" "X1983.04.16"
##  [41] "X1983.05.16" "X1983.06.16" "X1983.07.16" "X1983.08.16" "X1983.09.16"
##  [46] "X1983.10.16" "X1983.11.16" "X1983.12.16" "X1984.01.16" "X1984.02.15"
##  [51] "X1984.03.16" "X1984.04.16" "X1984.05.16" "X1984.06.16" "X1984.07.16"
##  [56] "X1984.08.16" "X1984.09.16" "X1984.10.16" "X1984.11.16" "X1984.12.16"
##  [61] "X1985.01.16" "X1985.02.15" "X1985.03.16" "X1985.04.16" "X1985.05.16"
##  [66] "X1985.06.16" "X1985.07.16" "X1985.08.16" "X1985.09.16" "X1985.10.16"
##  [71] "X1985.11.16" "X1985.12.16" "X1986.01.16" "X1986.02.15" "X1986.03.16"
##  [76] "X1986.04.16" "X1986.05.16" "X1986.06.16" "X1986.07.16" "X1986.08.16"
##  [81] "X1986.09.16" "X1986.10.16" "X1986.11.16" "X1986.12.16" "X1987.01.16"
##  [86] "X1987.02.15" "X1987.03.16" "X1987.04.16" "X1987.05.16" "X1987.06.16"
##  [91] "X1987.07.16" "X1987.08.16" "X1987.09.16" "X1987.10.16" "X1987.11.16"
##  [96] "X1987.12.16" "X1988.01.16" "X1988.02.15" "X1988.03.16" "X1988.04.16"
## [101] "X1988.05.16" "X1988.06.16" "X1988.07.16" "X1988.08.16" "X1988.09.16"
## [106] "X1988.10.16" "X1988.11.16" "X1988.12.16" "X1989.01.16" "X1989.02.15"
## [111] "X1989.03.16" "X1989.04.16" "X1989.05.16" "X1989.06.16" "X1989.07.16"
## [116] "X1989.08.16" "X1989.09.16" "X1989.10.16" "X1989.11.16" "X1989.12.16"
## [121] "X1990.01.16" "X1990.02.15" "X1990.03.16" "X1990.04.16" "X1990.05.16"
## [126] "X1990.06.16" "X1990.07.16" "X1990.08.16" "X1990.09.16" "X1990.10.16"
## [131] "X1990.11.16" "X1990.12.16" "X1991.01.16" "X1991.02.15" "X1991.03.16"
## [136] "X1991.04.16" "X1991.05.16" "X1991.06.16" "X1991.07.16" "X1991.08.16"
## [141] "X1991.09.16" "X1991.10.16" "X1991.11.16" "X1991.12.16" "X1992.01.16"
## [146] "X1992.02.15" "X1992.03.16" "X1992.04.16" "X1992.05.16" "X1992.06.16"
## [151] "X1992.07.16" "X1992.08.16" "X1992.09.16" "X1992.10.16" "X1992.11.16"
## [156] "X1992.12.16" "X1993.01.16" "X1993.02.15" "X1993.03.16" "X1993.04.16"
## [161] "X1993.05.16" "X1993.06.16" "X1993.07.16" "X1993.08.16" "X1993.09.16"
## [166] "X1993.10.16" "X1993.11.16" "X1993.12.16" "X1994.01.16" "X1994.02.15"
## [171] "X1994.03.16" "X1994.04.16" "X1994.05.16" "X1994.06.16" "X1994.07.16"
## [176] "X1994.08.16" "X1994.09.16" "X1994.10.16" "X1994.11.16" "X1994.12.16"
## [181] "X1995.01.16" "X1995.02.15" "X1995.03.16" "X1995.04.16" "X1995.05.16"
## [186] "X1995.06.16" "X1995.07.16" "X1995.08.16" "X1995.09.16" "X1995.10.16"
## [191] "X1995.11.16" "X1995.12.16" "X1996.01.16" "X1996.02.15" "X1996.03.16"
## [196] "X1996.04.16" "X1996.05.16" "X1996.06.16" "X1996.07.16" "X1996.08.16"
## [201] "X1996.09.16" "X1996.10.16" "X1996.11.16" "X1996.12.16" "X1997.01.16"
## [206] "X1997.02.15" "X1997.03.16" "X1997.04.16" "X1997.05.16" "X1997.06.16"
## [211] "X1997.07.16" "X1997.08.16" "X1997.09.16" "X1997.10.16" "X1997.11.16"
## [216] "X1997.12.16" "X1998.01.16" "X1998.02.15" "X1998.03.16" "X1998.04.16"
## [221] "X1998.05.16" "X1998.06.16" "X1998.07.16" "X1998.08.16" "X1998.09.16"
## [226] "X1998.10.16" "X1998.11.16" "X1998.12.16" "X1999.01.16" "X1999.02.15"
## [231] "X1999.03.16" "X1999.04.16" "X1999.05.16" "X1999.06.16" "X1999.07.16"
## [236] "X1999.08.16" "X1999.09.16" "X1999.10.16" "X1999.11.16" "X1999.12.16"
## [241] "X2000.01.16" "X2000.02.15" "X2000.03.16" "X2000.04.16" "X2000.05.16"
## [246] "X2000.06.16" "X2000.07.16" "X2000.08.16" "X2000.09.16" "X2000.10.16"
## [251] "X2000.11.16" "X2000.12.16" "X2001.01.16" "X2001.02.15" "X2001.03.16"
## [256] "X2001.04.16" "X2001.05.16" "X2001.06.16" "X2001.07.16" "X2001.08.16"
## [261] "X2001.09.16" "X2001.10.16" "X2001.11.16" "X2001.12.16" "X2002.01.16"
## [266] "X2002.02.15" "X2002.03.16" "X2002.04.16" "X2002.05.16" "X2002.06.16"
## [271] "X2002.07.16" "X2002.08.16" "X2002.09.16" "X2002.10.16" "X2002.11.16"
## [276] "X2002.12.16" "X2003.01.16" "X2003.02.15" "X2003.03.16" "X2003.04.16"
## [281] "X2003.05.16" "X2003.06.16" "X2003.07.16" "X2003.08.16" "X2003.09.16"
## [286] "X2003.10.16" "X2003.11.16" "X2003.12.16" "X2004.01.16" "X2004.02.15"
## [291] "X2004.03.16" "X2004.04.16" "X2004.05.16" "X2004.06.16" "X2004.07.16"
## [296] "X2004.08.16" "X2004.09.16" "X2004.10.16" "X2004.11.16" "X2004.12.16"
## [301] "X2005.01.16" "X2005.02.15" "X2005.03.16" "X2005.04.16" "X2005.05.16"
## [306] "X2005.06.16" "X2005.07.16" "X2005.08.16" "X2005.09.16" "X2005.10.16"
## [311] "X2005.11.16" "X2005.12.16" "X2006.01.16" "X2006.02.15" "X2006.03.16"
## [316] "X2006.04.16" "X2006.05.16" "X2006.06.16" "X2006.07.16" "X2006.08.16"
## [321] "X2006.09.16" "X2006.10.16" "X2006.11.16" "X2006.12.16" "X2007.01.16"
## [326] "X2007.02.15" "X2007.03.16" "X2007.04.16" "X2007.05.16" "X2007.06.16"
## [331] "X2007.07.16" "X2007.08.16" "X2007.09.16" "X2007.10.16" "X2007.11.16"
## [336] "X2007.12.16" "X2008.01.16" "X2008.02.15" "X2008.03.16" "X2008.04.16"
## [341] "X2008.05.16" "X2008.06.16" "X2008.07.16" "X2008.08.16" "X2008.09.16"
## [346] "X2008.10.16" "X2008.11.16" "X2008.12.16" "X2009.01.16" "X2009.02.15"
## [351] "X2009.03.16" "X2009.04.16" "X2009.05.16" "X2009.06.16" "X2009.07.16"
## [356] "X2009.08.16" "X2009.09.16" "X2009.10.16" "X2009.11.16" "X2009.12.16"
## [361] "X2010.01.16" "X2010.02.15" "X2010.03.16" "X2010.04.16" "X2010.05.16"
## [366] "X2010.06.16" "X2010.07.16" "X2010.08.16" "X2010.09.16" "X2010.10.16"
## [371] "X2010.11.16" "X2010.12.16" "X2011.01.16" "X2011.02.15" "X2011.03.16"
## [376] "X2011.04.16" "X2011.05.16" "X2011.06.16" "X2011.07.16" "X2011.08.16"
## [381] "X2011.09.16" "X2011.10.16" "X2011.11.16" "X2011.12.16" "X2012.01.16"
## [386] "X2012.02.15" "X2012.03.16" "X2012.04.16" "X2012.05.16" "X2012.06.16"
## [391] "X2012.07.16" "X2012.08.16" "X2012.09.16" "X2012.10.16" "X2012.11.16"
## [396] "X2012.12.16" "X2013.01.16" "X2013.02.15" "X2013.03.16" "X2013.04.16"
## [401] "X2013.05.16" "X2013.06.16" "X2013.07.16" "X2013.08.16" "X2013.09.16"
## [406] "X2013.10.16" "X2013.11.16" "X2013.12.16" "X2014.01.16" "X2014.02.15"
## [411] "X2014.03.16" "X2014.04.16" "X2014.05.16" "X2014.06.16" "X2014.07.16"
## [416] "X2014.08.16" "X2014.09.16" "X2014.10.16" "X2014.11.16" "X2014.12.16"

You can use a similar technique to select any interval.

Selecting time intervals in raster

Fernando De Sales (fdesales@sdsu.edu)