diff --git a/pyproject.toml b/pyproject.toml
index a997dcc..3e3cab8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,6 +23,7 @@ dependencies = [
     "scipy>=1.11",
     "h5netcdf>=1.8.1",
     "h5py>=3.16.0",
+    "dask>=2026.3.0",
 ]
 
 [tool.uv.sources]
diff --git a/src/data/preprocess.py b/src/data/preprocess.py
index 01b8e76..20ab961 100644
--- a/src/data/preprocess.py
+++ b/src/data/preprocess.py
@@ -69,7 +69,7 @@ def load_era5_city(city: str) -> xr.Dataset:
     combined = xr.open_mfdataset(
         nc_files,
         combine="by_coords",
-        engine="netcdf4",
+        engine="h5netcdf",
         chunks=None,  # 小区域数据直接加载到内存
     )