add detrend

bopen · Feb 7, 2024 · b5f5896 · b5f5896
1 parent d787613
commit b5f5896
Showing 1 changed file with 14 additions and 3 deletions.
diff --git a/notebooks/wp3/WIP-hit_rate.ipynb b/notebooks/wp3/WIP-hit_rate.ipynb
@@ -54,6 +54,10 @@
     "year_start_hindcast = 1993\n",
     "year_stop_hindcast = 2016\n",
     "\n",
+    "# Detrend\n",
+    "detrend = True\n",
+    "assert isinstance(detrend, bool)\n",
+    "\n",
     "# Variable\n",
     "variables = [\n",
     "    \"2m_temperature\",\n",
@@ -213,7 +217,7 @@
     "    return ds\n",
     "\n",
     "\n",
-    "def compute_tercile_occupation(ds, region):\n",
+    "def compute_tercile_occupation(ds, region, detrend):\n",
     "    # Mask region\n",
     "    mask = regionmask.defined_regions.srex.mask(ds)\n",
     "    index = regionmask.defined_regions.srex.map_keys(region)\n",
@@ -224,6 +228,13 @@
     "    else:\n",
     "        ds = ds.rename(forecast_reference_time=\"valid_time\")\n",
     "\n",
+    "    if detrend:\n",
+    "        (da,) = ds.data_vars.values()\n",
+    "        time = da[\"valid_time\"]\n",
+    "        fit = ds.polyfit(time.name, deg=1, w=time.dt.days_in_month)\n",
+    "        da -= xr.polyval(time, fit.polyfit_coefficients)\n",
+    "        ds = da.to_dataset()\n",
+    "\n",
     "    # Compute anomaly\n",
     "    climatology = diagnostics.time_weighted_mean(ds, time_name=\"valid_time\")\n",
     "    climatology = climatology.mean(set(climatology.dims) & {\"realization\"})\n",
@@ -284,7 +295,7 @@
     "            chunks=chunks,\n",
     "            transform_chunks=False,\n",
     "            transform_func=compute_tercile_occupation,\n",
-    "            transform_func_kwargs={\"region\": region},\n",
+    "            transform_func_kwargs={\"region\": region, \"detrend\": detrend},\n",
     "        )\n",
     "        (da,) = ds.data_vars.values()\n",
     "        dataarrays.append(da.rename(variable))\n",
@@ -329,7 +340,7 @@
     "                    chunks=chunks,\n",
     "                    transform_chunks=False,\n",
     "                    transform_func=compute_tercile_occupation,\n",
-    "                    transform_func_kwargs={\"region\": region},\n",
+    "                    transform_func_kwargs={\"region\": region, \"detrend\": detrend},\n",
     "                    backend_kwargs={\n",
     "                        \"time_dims\": (\n",
     "                            \"forecastMonth\",\n",