Preserve formatting of reference time units under pandas 2.0.0

doc/whats-new.rst

@@ -46,6 +46,10 @@ Bug fixes
   By `Jimmy Westling <https://github.com/illviljan>`_.
 - Improved performance in ``open_dataset`` for datasets with large object arrays (:issue:`7484`, :pull:`7494`).
   By `Alex Goodman <https://github.com/agoodm>`_ and `Deepak Cherian <https://github.com/dcherian>`_.
+- Ensure the formatting of time encoding reference dates outside the range of
+  nanosecond-precision datetimes remains the same under pandas version 2.0.0
+  (:issue:`7420`, :pull:`7441`).  By `Spencer Clark
+  <https://github.com/spencerkclark>`_.
 
 Documentation
 ~~~~~~~~~~~~~

xarray/core/formatting.py

@@ -114,9 +114,9 @@ def calc_max_rows_last(max_rows: int) -> int:
 
 def format_timestamp(t):
     """Cast given object to a Timestamp and return a nicely formatted string"""
-    # Timestamp is only valid for 1678 to 2262
     try:
-        datetime_str = str(pd.Timestamp(t))
+        timestamp = pd.Timestamp(t)
+        datetime_str = timestamp.strftime("%Y-%m-%d %H:%M:%s")
     except OutOfBoundsDatetime:
         datetime_str = str(t)