diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5a6cc51..bcadfed 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.11]
+        python-version: ["3.10"]
 
     steps:
       - name: Checkout repository
diff --git a/pyproject.toml b/pyproject.toml
index c7ae8fa..ed03433 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "rasters"
-version = "1.4.6"
+version = "1.5.0"
 description = "raster processing toolkit"
 readme = "README.md"
 authors = [
diff --git a/rasters/bias_correct.py b/rasters/bias_correct.py
new file mode 100644
index 0000000..1b4263a
--- /dev/null
+++ b/rasters/bias_correct.py
@@ -0,0 +1,23 @@
+from .raster import Raster
+from .where import where
+
+DEFAULT_UPSAMPLING = "average"
+DEFAULT_DOWNSAMPLING = "linear"
+
+def bias_correct(
+        coarse_image: Raster,
+        fine_image: Raster,
+        upsampling: str = "average",
+        downsampling: str = "linear",
+        return_bias: bool = False):
+    fine_geometry = fine_image.geometry
+    coarse_geometry = coarse_image.geometry
+    upsampled = fine_image.to_geometry(coarse_geometry, resampling=upsampling)
+    bias_coarse = upsampled - coarse_image
+    bias_fine = bias_coarse.to_geometry(fine_geometry, resampling=downsampling)
+    bias_corrected_fine = fine_image - bias_fine
+
+    if return_bias:
+        return bias_corrected_fine, bias_fine
+    else:
+        return bias_corrected_fine
diff --git a/rasters/linear_downscale.py b/rasters/linear_downscale.py
new file mode 100644
index 0000000..e5063cb
--- /dev/null
+++ b/rasters/linear_downscale.py
@@ -0,0 +1,53 @@
+from .raster import Raster
+from .where import where
+
+DEFAULT_UPSAMPLING = "average"
+DEFAULT_DOWNSAMPLING = "linear"
+
+def linear_downscale(
+        coarse_image: Raster,
+        fine_image: Raster,
+        upsampling: str = "average",
+        downsampling: str = "cubic",
+        use_gap_filling: bool = False,
+        apply_scale: bool = True,
+        apply_bias: bool = True,
+        return_scale_and_bias: bool = False) -> Raster:
+    if upsampling is None:
+        upsampling = DEFAULT_UPSAMPLING
+
+    if downsampling is None:
+        downsampling = DEFAULT_DOWNSAMPLING
+
+    coarse_geometry = coarse_image.geometry
+    fine_geometry = fine_image.geometry
+    upsampled = fine_image.to_geometry(coarse_geometry, resampling=upsampling)
+
+    if apply_scale:
+        scale_coarse = coarse_image / upsampled
+        scale_coarse = where(coarse_image == 0, 0, scale_coarse)
+        scale_coarse = where(upsampled == 0, 0, scale_coarse)
+        scale_fine = scale_coarse.to_geometry(fine_geometry, resampling=downsampling)
+        scale_corrected_fine = fine_image * scale_fine
+        fine_image = scale_corrected_fine
+    else:
+        scale_fine = fine_image * 0 + 1
+
+    if apply_bias:
+        upsampled = fine_image.to_geometry(coarse_geometry, resampling=upsampling)
+        bias_coarse = upsampled - coarse_image
+        bias_fine = bias_coarse.to_geometry(fine_geometry, resampling=downsampling)
+        bias_corrected_fine = fine_image - bias_fine
+        fine_image = bias_corrected_fine
+    else:
+        bias_fine = fine_image * 0
+
+    if use_gap_filling:
+        gap_fill = coarse_image.to_geometry(fine_geometry, resampling=downsampling)
+        fine_image = fine_image.fill(gap_fill)
+
+    if return_scale_and_bias:
+        fine_image["scale"] = scale_fine
+        fine_image["bias"] = bias_fine
+
+    return fine_image
diff --git a/rasters/rasters.py b/rasters/rasters.py
index 6b39d67..57aabcb 100644
--- a/rasters/rasters.py
+++ b/rasters/rasters.py
@@ -24,5 +24,7 @@
 from .clip import clip
 from .center_aeqd import center_aeqd
 from .local_UTM_proj4 import local_UTM_proj4
+from .linear_downscale import linear_downscale
+from .bias_correct import bias_correct
 
 __author__ = "Gregory Halverson"
diff --git a/rasters/version.txt b/rasters/version.txt
index c514bd8..bc80560 100644
--- a/rasters/version.txt
+++ b/rasters/version.txt
@@ -1 +1 @@
-1.4.6
+1.5.0