diff --git a/notebooks/wp4/cmip6_sea_ice_thickness_bias_maps.ipynb b/notebooks/wp4/cmip6_sea_ice_thickness_bias_maps.ipynb
index 429fec1..e57abe2 100644
--- a/notebooks/wp4/cmip6_sea_ice_thickness_bias_maps.ipynb
+++ b/notebooks/wp4/cmip6_sea_ice_thickness_bias_maps.ipynb
@@ -23,9 +23,9 @@
    "metadata": {},
    "outputs": [],
    "source": [
+    "import calendar\n",
     "import warnings\n",
     "\n",
-    "import calendar\n",
     "import cartopy.crs as ccrs\n",
     "import matplotlib.pyplot as plt\n",
     "import pandas as pd\n",
@@ -240,9 +240,9 @@
     "da = da.where(da.sel(product=\"satellite\").notnull())\n",
     "for dim in ds.dims:\n",
     "    da = da.dropna(dim, how=\"all\")\n",
-    "for month, da_month in da.groupby(\"month\"):\n",
+    "for month in da[\"month\"].values:\n",
     "    facet = plot.projected_map(\n",
-    "        da_month,\n",
+    "        da.sel(month=month),\n",
     "        col=\"product\",\n",
     "        row=\"satellite\",\n",
     "        vmin=0,\n",