diff --git a/src/finam_mhm_module/__init__.py b/src/finam_mhm_module/__init__.py
index 23a644a2e30ef39961df939476eee7ce3b5439e7..355a541af585818043b1dabe67a013fe93a891f5 100644
--- a/src/finam_mhm_module/__init__.py
+++ b/src/finam_mhm_module/__init__.py
@@ -1 +1,2 @@
 from .mhm import Mhm
+from .lai_adapter import YearlyToMonthly
diff --git a/src/finam_mhm_module/lai_adapter.py b/src/finam_mhm_module/lai_adapter.py
new file mode 100644
index 0000000000000000000000000000000000000000..d70e69b74a881645d9634e9c2039cff50b4a7d65
--- /dev/null
+++ b/src/finam_mhm_module/lai_adapter.py
@@ -0,0 +1,35 @@
+from datetime import datetime
+
+from finam.core.sdk import AAdapter
+
+
+class YearlyToMonthly(AAdapter):
+    """Disaggregates yearly LAI to a stack of monthly LAIs."""
+
+    def __init__(self, lai_curve):
+        super().__init__()
+        self.data = None
+        self.month = 0
+        if len(lai_curve) != 12:
+            raise ValueError("LAI curve must be an array of 12 values")
+        self.lai_curve = lai_curve
+
+    def source_changed(self, time):
+        if not isinstance(time, datetime):
+            raise ValueError("Time must be of type datetime")
+
+        self.data = self.pull_data(time)
+        self.month = time.month
+
+        self.notify_targets(time)
+
+    def get_data(self, time):
+        if not isinstance(time, datetime):
+            raise ValueError("Time must be of type datetime")
+
+        new_month = time.month
+        lai = []
+        for m in range(self.month - 1, new_month):
+            lai.append(self.data * self.lai_curve[m])
+
+        return lai
diff --git a/tests/test_lai_adapter.py b/tests/test_lai_adapter.py
new file mode 100644
index 0000000000000000000000000000000000000000..d5defe70bab56bc6d7c83d7a51b4bc96e50f9f58
--- /dev/null
+++ b/tests/test_lai_adapter.py
@@ -0,0 +1,9 @@
+import unittest
+from datetime import datetime, timedelta
+
+from finam_mhm_module import YearlyToMonthly
+
+
+class TestLaiAdapter(unittest.TestCase):
+    def test_adapter(self):
+        pass