diff --git a/notebooks/foundations/energy-balance-model.ipynb b/notebooks/foundations/energy-balance-model.ipynb
index 1592f05..56684f0 100644
--- a/notebooks/foundations/energy-balance-model.ipynb
+++ b/notebooks/foundations/energy-balance-model.ipynb
@@ -95,21 +95,37 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Your first content section"
+    "## 4. Cloud Feedback"
    ]
   },
   {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "This is where you begin your first section of material, loosely tied to your objectives stated up front. Tie together your notebook as a narrative, with interspersed Markdown text, images, and more as necessary,"
+    "The cloud feedback mechanism is the most complex feedback discussed in this tutorial. This is because clouds interact with both shortwave (SW) and longwave (LW) radiation and exert varying radiative effects depending on their properties (cloud type, height, optical depth, liquid and ice water content, particule sizes, etc)."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "![High cloud versus low cloud radiative effects](../images/2-whycloudsare.jpg)<br>\n",
+    "[Credit: Paulo Ceppi](https://phys.org/news/2020-09-clouds-piece-climate-puzzle.html)"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 3,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Hello world!\n"
+     ]
+    }
+   ],
    "source": [
     "# as well as any and all of your code cells\n",
     "print(\"Hello world!\")"
diff --git a/notebooks/images/2-whycloudsare.jpg b/notebooks/images/2-whycloudsare.jpg
new file mode 100644
index 0000000..91d38b7
Binary files /dev/null and b/notebooks/images/2-whycloudsare.jpg differ