diff --git a/c3s_eqc_automatic_quality_control/download.py b/c3s_eqc_automatic_quality_control/download.py
index dd3aa3d..810cd25 100644
--- a/c3s_eqc_automatic_quality_control/download.py
+++ b/c3s_eqc_automatic_quality_control/download.py
@@ -18,11 +18,13 @@
 # limitations under the License.
 
 import calendar
+import contextlib
 import fnmatch
 import functools
 import itertools
+import os
 import pathlib
-from collections.abc import Callable
+from collections.abc import Callable, Iterator
 from typing import Any
 
 import cacholote
@@ -48,6 +50,19 @@
 _SORTED_REQUEST_PARAMETERS = ("area", "grid")
 
 
+@contextlib.contextmanager
+def _set_env(**kwargs: Any) -> Iterator[None]:
+    old_environ = dict(os.environ)
+    try:
+        os.environ.update(
+            {k.upper(): str(v) for k, v in kwargs.items() if v is not None}
+        )
+        yield
+    finally:
+        os.environ.clear()
+        os.environ.update(old_environ)
+
+
 def compute_stop_date(switch_month_day: int | None = None) -> pd.Period:
     today = pd.Timestamp.today()
     if switch_month_day is None:
@@ -306,7 +321,8 @@ def get_sources(
 ) -> list[str]:
     source: set[str] = set()
 
-    for request in tqdm.tqdm(request_list, disable=len(request_list) <= 1):
+    disable = os.getenv("TQDM_DISABLE", "False") == "True"
+    for request in tqdm.tqdm(request_list, disable=disable):
         data = _cached_retrieve(collection_id, request)
         if content := getattr(data, "_content", None):
             source.update(map(str, content))
@@ -479,6 +495,7 @@ def download_and_transform(
     n_jobs: int | None = None,
     invalidate_cache: bool | None = None,
     cached_open_mfdataset_kwargs: bool | dict[str, Any] = {},
+    quiet: bool = False,
     **open_mfdataset_kwargs: Any,
 ) -> xr.Dataset:
     """
@@ -513,6 +530,8 @@ def download_and_transform(
     cached_open_mfdataset_kwargs: bool | dict
         Kwargs to be passed on to xr.open_mfdataset for cached files.
         If True, use open_mfdataset_kwargs used for raw files.
+    quiet: bool
+        Whether to disable progress bars.
     **open_mfdataset_kwargs:
         Kwargs to be passed on to xr.open_mfdataset for raw files.
 
@@ -520,6 +539,8 @@ def download_and_transform(
     -------
     xr.Dataset
     """
+    assert isinstance(quiet, bool)
+
     if n_jobs is None:
         n_jobs = N_JOBS
 
@@ -557,12 +578,15 @@ def download_and_transform(
     if use_cache and transform_chunks:
         # Cache each chunk transformed
         sources = []
-        for request in tqdm.tqdm(request_list):
+        for request in tqdm.tqdm(request_list, disable=quiet):
             if invalidate_cache:
                 cacholote.delete(
                     func.func, *func.args, request_list=[request], **func.keywords
                 )
-            with cacholote.config.set(return_cache_entry=True):
+            with (
+                cacholote.config.set(return_cache_entry=True),
+                _set_env(tqdm_disable=True),
+            ):
                 sources.append(func(request_list=[request]).result["args"][0]["href"])
         ds = xr.open_mfdataset(sources, **cached_open_mfdataset_kwargs)
     else:
@@ -571,7 +595,8 @@ def download_and_transform(
             cacholote.delete(
                 func.func, *func.args, request_list=request_list, **func.keywords
             )
-        ds = func(request_list=request_list)
+        with _set_env(tqdm_disable=quiet):
+            ds = func(request_list=request_list)
 
     ds.attrs.pop("coordinates", None)  # Previously added to guarantee roundtrip
     return ds