diff --git a/ChangeLog b/ChangeLog
index b110284d9f00a8ae94c1396618bd6a761822ee44..01df149ee9170abe736e6155af16c8e6dadd7c1a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2025-03-30  Uwe Schulzweida
+
+	* changed chunkSizeLim from 16mb to 4mb
+
 2025-03-27  Uwe Schulzweida
 
 	* vlistChangeZaxis: added call to delete_chunks() (bug fix)
diff --git a/src/cdf_write.c b/src/cdf_write.c
index 4e5ece4fbaca9d08a7ee32710e8535ba80d2a990..d8bec6868cc7222cefd075daaa1bdfce079ed751 100644
--- a/src/cdf_write.c
+++ b/src/cdf_write.c
@@ -701,8 +701,9 @@ calc_chunksize(size_t chunkSizeLim, size_t size)
   return chunkSize;
 }
 
-static const size_t chunkSizeMin = 262144;    // 256k
-static const size_t chunkSizeLim = 16777216;  // 16m
+static const size_t chunkSizeMin = 262144;  // 256kb
+// static const size_t chunkSizeLim = 16777216;  // 16mb
+static const size_t chunkSizeLim = 4194304;  // 4mb
 
 size_t
 auto_chunksize_y(size_t gridsize, size_t xsize, size_t ysize)