diff --git a/pyproject.toml b/pyproject.toml
index 96147221401..db64d7a18c5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -330,6 +330,8 @@ filterwarnings = [
   "default:Using a non-tuple sequence for multidimensional indexing is deprecated:FutureWarning",
   "default:Duplicate dimension names present:UserWarning:xarray.namedarray.core",
   "default:::xarray.tests.test_strategies",
+  # TODO: remove once we know how to deal with a changed signature in protocols
+  "ignore:__array__ implementation doesn't accept a copy keyword, so passing copy=False failed.",
 ]
 
 log_cli_level = "INFO"
diff --git a/xarray/core/dataset.py b/xarray/core/dataset.py
index 57ddcd9d39d..747b26ce6e9 100644
--- a/xarray/core/dataset.py
+++ b/xarray/core/dataset.py
@@ -1524,7 +1524,7 @@ def __iter__(self) -> Iterator[Hashable]:
 
     else:
 
-        def __array__(self, dtype=None):
+        def __array__(self, dtype=None, copy=None):
             raise TypeError(
                 "cannot directly convert an xarray.Dataset into a "
                 "numpy array. Instead, create an xarray.DataArray "
@@ -8937,9 +8937,7 @@ def polyfit(
         lhs = np.vander(x, order)
 
         if rcond is None:
-            rcond = (
-                x.shape[0] * np.core.finfo(x.dtype).eps  # type: ignore[attr-defined]
-            )
+            rcond = x.shape[0] * np.finfo(x.dtype).eps
 
         # Weights:
         if w is not None:
diff --git a/xarray/core/datatree.py b/xarray/core/datatree.py
index 48c714b697c..9c4462e3aff 100644
--- a/xarray/core/datatree.py
+++ b/xarray/core/datatree.py
@@ -624,7 +624,7 @@ def __bool__(self) -> bool:
     def __iter__(self) -> Iterator[Hashable]:
         return itertools.chain(self.ds.data_vars, self.children)
 
-    def __array__(self, dtype=None):
+    def __array__(self, dtype=None, copy=None):
         raise TypeError(
             "cannot directly convert a DataTree into a "
             "numpy array. Instead, create an xarray.DataArray "
diff --git a/xarray/tests/test_assertions.py b/xarray/tests/test_assertions.py
index 59861ef7981..f7e49a0f3de 100644
--- a/xarray/tests/test_assertions.py
+++ b/xarray/tests/test_assertions.py
@@ -149,7 +149,7 @@ def dims(self):
             warnings.warn("warning in test")
             return super().dims
 
-        def __array__(self):
+        def __array__(self, dtype=None, copy=None):
             warnings.warn("warning in test")
             return super().__array__()
 
diff --git a/xarray/tests/test_formatting.py b/xarray/tests/test_formatting.py
index cb765ce91f8..2c40ac88f98 100644
--- a/xarray/tests/test_formatting.py
+++ b/xarray/tests/test_formatting.py
@@ -877,7 +877,7 @@ def test_lazy_array_wont_compute() -> None:
     from xarray.core.indexing import LazilyIndexedArray
 
     class LazilyIndexedArrayNotComputable(LazilyIndexedArray):
-        def __array__(self, dtype=None):
+        def __array__(self, dtype=None, copy=None):
             raise NotImplementedError("Computing this array is not possible.")
 
     arr = LazilyIndexedArrayNotComputable(np.array([1, 2]))