diff --git a/modules/Units/R/transform_units_precipitation.R b/modules/Units/R/transform_units_precipitation.R
index a24ef851559928b49537de62402375ac0c829ee0..5cc1e812fd31a8aec507c3cae283707a30c273b8 100644
--- a/modules/Units/R/transform_units_precipitation.R
+++ b/modules/Units/R/transform_units_precipitation.R
@@ -1,80 +1,70 @@
 transform_units_precipitation <- function(data, original_units, new_units,
                                           var_name, freq, flux = FALSE, ncores = NULL,
                                           var_index = 1) {
-  ## TODO: Hard-coded subsetting
+
 ## TODO consider higher frequencies (e.g. 6hourly) 
 ## could create a constant hours <- 24 or hours <- 6 and use the same code
+
+  data_arr <- data[[1]]$data
+  data_list <- asplit(data_arr, which(names(dim(data_arr)) == "var"))
+
+
   if (original_units == "ms-1") {
     if (new_units == "mm") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] * 3600 * 24 * 1000
-      data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'mm'
+      data_list[[var_index]] <- data_list[[var_index]] * 3600 * 24 * 1000
+      data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "mm"
     } else if (new_units == "m") {
-     data[[1]]$data[ , var_index, , , , , , , ] <- 
-       data[[1]]$data[ , var_index, , , , , , , ] * 3600 * 24
-     data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'm'
+      data_list[[var_index]] <- data_list[[var_index]] * 3600 * 24
+      data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'm'
     } else if (new_units == "kgm-2s-1") {
-     data[[1]]$data[ , var_index, , , , , , , ] <- 
-       data[[1]]$data[ , var_index, , , , , , , ] * 1000 
-     data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'kg m-2 s-1'
+      data_list[[var_index]] <- data_list[[var_index]] * 1000
+      data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'kg m-2 s-1'
     } else {
-      stop(paste("Unknown transformation from", original_units, "to",
-                 new_units))
+      stop(paste("Unknown transformation from", original_units, "to", new_units))
     }
   } else if (original_units == "mm") {
     if (new_units == "ms-1") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] / (3600 * 24 * 1000)
+      data_list[[var_index]] <- data_list[[var_index]] / (3600 * 24 * 1000)
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'm s-1'
     } else if (new_units == "m") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] / 1000
+      data_list[[var_index]] <- data_list[[var_index]] / 1000
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'm'
     } else if (new_units == "kgm-2s-1") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] / (3600 * 24 )
+      data_list[[var_index]] <- data_list[[var_index]] / (3600 * 24)
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'kg m-2 s-1'
     } else {
-      stop(paste("Unknown transformation from", original_units, "to",
-                 new_units))
+      stop(paste("Unknown transformation from", original_units, "to", new_units))
     }
   } else if (original_units == "m") {
     if (new_units == "ms-1") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] / (3600 * 24)
+      data_list[[var_index]] <- data_list[[var_index]] / (3600 * 24)
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'm s-1'
     } else if (new_units == "mm") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] * 1000
+      data_list[[var_index]] <- data_list[[var_index]] * 1000
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'mm'
     } else if (new_units == "kgm-2s-1") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] * 1000 / (3600 * 24) 
+      data_list[[var_index]] <- data_list[[var_index]] * 1000 / (3600 * 24)
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'kg m-2 s-1'
     } else {
-      stop(paste("Unknown transformation from", original_units, "to",
-                 new_units))
+      stop(paste("Unknown transformation from", original_units, "to", new_units))
     }
   } else if (original_units == "kgm-2s-1") {
     if (new_units == "ms-1") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] / 1000
+      data_list[[var_index]] <- data_list[[var_index]] / 1000
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'm s-1'
     } else if (new_units == "mm") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] * 3600 * 24
+      data_list[[var_index]] <- data_list[[var_index]] * 3600 * 24
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'mm'
     } else if (new_units == "m") {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] * 3600 * 24 / 1000
+      data_list[[var_index]] <- data_list[[var_index]] * 3600 * 24 / 1000
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'm'
     } else {
-      stop(paste("Unknown transformation from", original_units, "to",
-                 new_units))
+      stop(paste("Unknown transformation from", original_units, "to", new_units))
     }
   } else {
     stop("Unknown precipitation units transformation")
   }
+
   if (flux) {
     data[[1]]$attrs$Variable$metadata[[var_name]]$units <- paste0(
       data[[1]]$attrs$Variable$metadata[[var_name]]$units, "/day")
@@ -84,9 +74,8 @@ transform_units_precipitation <- function(data, original_units, new_units,
       time_pos <- which(lapply(data[[1]]$attrs$Variable$metadata[[var_name]]$dim,
                                function(x) {x$name}) == 'time')
       cal <- tolower(data[[1]]$attrs$Variable$metadata[[var_name]]$dim[[time_pos]]$calendar)
-      data_subset <- Subset(data[[1]]$data, along = "var", indices = var_index, drop = 'selected')
-      data[[1]]$data[ , var_index, , , , , , , ] <-
-        Apply(list(data_subset, data[[1]]$attrs$Dates),
+      data_list[[var_index]] <-
+        Apply(list(data_list[[var_index]], data[[1]]$attrs$Dates),
               target_dim = list(c('syear'), c('syear')),
               extra_info = list(cal = cal, days_in_month = .days_in_month),
               fun = function(x, y) {
@@ -96,9 +85,17 @@ transform_units_precipitation <- function(data, original_units, new_units,
               }, ncores = ncores)$output1
     }
   }
+
+  # Combine list back to array
+  data_arr <- array(unlist(data_list),
+                    dim = c(dim(data_list[[1]]), var = length(data_list)))
+  data[[1]]$data <- aperm(data_arr, match(names(dim(data[[1]]$data)),
+                          names(dim(data_arr))))
+
   return(data)
 }
 
+
 .days_in_month <- function(x, cal) {
   if (cal %in% c('gregorian', 'standard', 'proleptic_gregorian')) {
     N_DAYS_IN_MONTHS <- lubridate:::N_DAYS_IN_MONTHS
diff --git a/modules/Units/R/transform_units_pressure.R b/modules/Units/R/transform_units_pressure.R
index 9712e9fe54b82638fb201bf276cbdc3f871553c9..58d51b1e98df3a5f1758a45ab7ee7817cc670267 100644
--- a/modules/Units/R/transform_units_pressure.R
+++ b/modules/Units/R/transform_units_pressure.R
@@ -1,33 +1,37 @@
 transform_units_pressure <- function(data, original_units, new_units, var_name,
                                      var_index = 1) {
 
-  ## TODO: Hard-coded subsetting
+  data_arr <- data[[1]]$data
+  data_list <- asplit(data_arr, which(names(dim(data_arr)) == "var"))
+
   if (original_units == 'pa') {
+    data_list[[var_index]] <- data_list[[var_index]] / 100
     if (new_units == 'hpa') {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] /100
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'hPa'
     } else if (new_units == 'mb') {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] /100
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'mb'
     }
   } else if (original_units == 'hpa') {
     if (new_units == 'pa') {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] * 100
+      data_list[[var_index]] <- data_list[[var_index]] * 100
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "Pa"
     } else if (new_units == "mb") {
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "mb"
     }
   } else if (original_units == "mb") {
     if (new_units == 'pa') {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] * 100
+      data_list[[var_index]] <- data_list[[var_index]] * 100
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "Pa"
     } else if (new_units == "hPa") {
       data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "hPa"
-    }  
+    }
   }
+
+  # Combine list back to array
+  data_arr <- array(unlist(data_list),
+                    dim = c(dim(data_list[[1]]), var = length(data_list)))
+  data[[1]]$data <- aperm(data_arr, match(names(dim(data[[1]]$data)),
+                          names(dim(data_arr))))
+
   return(data)
 }
diff --git a/modules/Units/R/transform_units_temperature.R b/modules/Units/R/transform_units_temperature.R
index 366f0d34cee4a523845351d0b8ffea12c239e037..985483f08897d6f0e84a40f2db66aab89f2c3bec 100644
--- a/modules/Units/R/transform_units_temperature.R
+++ b/modules/Units/R/transform_units_temperature.R
@@ -1,17 +1,22 @@
 transform_units_temperature <- function(data, original_units, new_units,
-                                        var_name, var_index = 1,
-                                        var_dim = "var") {
-  ## TODO: Hard-coded subsetting
+                                        var_name, var_index = 1) {
+
+  data_arr <- data[[1]]$data
+  data_list <- asplit(data_arr, which(names(dim(data_arr)) == "var"))
   if (original_units == 'c' & new_units == 'k') {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] + 273.15
-      data[[1]]$attrs$Variable$metadata[[var_name]]$units <- 'K'
+    data_list[[var_index]] <- data_list[[var_index]] + 273.15
+    data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "K"
   }
   if (original_units == 'k' & new_units == 'c') {
-      data[[1]]$data[ , var_index, , , , , , , ] <- 
-        data[[1]]$data[ , var_index, , , , , , , ] - 273.15
-      data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "C"
-
+    data_list[[var_index]] <- data_list[[var_index]] - 273.15
+    data[[1]]$attrs$Variable$metadata[[var_name]]$units <- "C"
   }
+
+  # Combine list back to array
+  data_arr <- array(unlist(data_list),
+                    dim = c(dim(data_list[[1]]), var = length(data_list)))
+  data[[1]]$data <- aperm(data_arr, match(names(dim(data[[1]]$data)), 
+                          names(dim(data_arr))))
+
   return(data)
 }