Feature/add dewpoint temperature

README.rst

@@ -43,6 +43,7 @@ Atlite can process the following weather data fields and can convert them into f
 .. * Surface roughness
 .. * Height maps
 .. * Soil temperature
+.. * Dewpoint temperature
 
 
 .. * Wind power generation for a given turbine type

atlite/convert.py

@@ -241,6 +241,21 @@ def soil_temperature(cutout, **params):
     return cutout.convert_and_aggregate(convert_func=convert_soil_temperature, **params)
 
 
+# dewpoint temperature
+def convert_dewpoint_temperature(ds):
+    """
+    Return dewpoint temperature.
+    """
+    # Temperature is in Kelvin
+    return ds["dewpoint temperature"] - 273.15
+
+
+def dewpoint_temperature(cutout, **params):
+    return cutout.convert_and_aggregate(
+        convert_func=convert_dewpoint_temperature, **params
+    )
+
+
 def convert_coefficient_of_performance(ds, source, sink_T, c0, c1, c2):
     assert source in ["air", "soil"], NotImplementedError(
         "'source' must be one of  ['air', 'soil']"

atlite/cutout.py

@@ -35,6 +35,7 @@
     coefficient_of_performance,
     convert_and_aggregate,
     csp,
+    dewpoint_temperature,
     heat_demand,
     hydro,
     irradiation,
@@ -681,6 +682,8 @@ def layout_from_capacity_list(self, data, col="Capacity"):
 
     soil_temperature = soil_temperature
 
+    dewpoint_temperature = dewpoint_temperature
+
     coefficient_of_performance = coefficient_of_performance
 
     solar_thermal = solar_thermal

atlite/datasets/era5.py

@@ -53,7 +53,7 @@ def nullcontext():
         "solar_altitude",
         "solar_azimuth",
     ],
-    "temperature": ["temperature", "soil temperature"],
+    "temperature": ["temperature", "soil temperature", "dewpoint temperature"],
     "runoff": ["runoff"],
 }
 
@@ -199,11 +199,22 @@ def get_data_temperature(retrieval_params):
     Get wind temperature for given retrieval parameters.
     """
     ds = retrieve_data(
-        variable=["2m_temperature", "soil_temperature_level_4"], **retrieval_params
+        variable=[
+            "2m_temperature",
+            "soil_temperature_level_4",
+            "2m_dewpoint_temperature",
+        ],
+        **retrieval_params,
     )
 
     ds = _rename_and_clean_coords(ds)
-    ds = ds.rename({"t2m": "temperature", "stl4": "soil temperature"})
+    ds = ds.rename(
+        {
+            "t2m": "temperature",
+            "stl4": "soil temperature",
+            "d2m": "dewpoint temperature",
+        }
+    )
 
     return ds
 

test/test_preparation_and_conversion.py

@@ -273,6 +273,16 @@ def soil_temperature_test(cutout):
     assert demand.sum() > 0
 
 
+def dewpoint_temperature_test(cutout):
+    """
+    Test the atlite.Cutout.dewpoint_temperature function with different
+    settings.
+    """
+    demand = cutout.dewpoint_temperature()
+    assert demand.notnull().all()
+    assert demand.sum() > 0
+
+
 def wind_test(cutout):
     """
     Test the atlite.Cutout.wind function with two different layouts.
@@ -684,6 +694,10 @@ def test_heat_demand_era5(cutout_era5):
     def test_soil_temperature_era5(cutout_era5):
         return soil_temperature_test(cutout_era5)
 
+    @staticmethod
+    def test_dewpoint_temperature_era5(cutout_era5):
+        return dewpoint_temperature_test(cutout_era5)
+
     @staticmethod
     def test_line_rating_era5(cutout_era5):
         return line_rating_test(cutout_era5)