.. _sec-data-srf:

Spectral response functions
===========================

A spectral response function (SRF) dataset provides tabulated values of the
spectral response of a radiometric instrument.
Eradiate's built-in SRF datasets are managed by the data store
(see :ref:`sec-data-intro` for details).

Format
------

* **Format** ``xarray.Dataset`` (in-memory), NetCDF (storage)
* **Dimensions**

  * ``w``: radiation wavelength

* **Coordinates** (all dimension coordinates; when relevant, ``units`` are
  required and specified in the units metadata field)

  * ``w`` float [length]

* **Data variables** (when relevant, units are required and specified in the
  units metadata field)

  * ``srf`` (``w``): spectral response function [dimensionless]
  * ``srf_u`` (``w``): uncertainty on the ``srf`` data variable [dimensionless]

.. dropdown:: Full validation schema

   .. literalinclude:: /resources/data_schemas/srf_dataset_v1.yml

Naming convention
^^^^^^^^^^^^^^^^^

SRF data files are usually named ``{platform}-{instrument}-{band}.nc`` where:

* ``platform`` identifies the platform (*e.g.* satellite's name);
* ``instrument`` identifies the instrument onboard the platform;
* ``band`` specifies the spectral band.

For example, the spectral response function data set of the SLSTR instrument
onboard Sentinel-3B and in the spectral band 5 has the identifier
``sentinel_3b-slstr-5``.

Dataset index
-------------

.. important::

    The following datasets are processed to minimize the amount of computation
    performed for parts of the spectrum that will result in a low contribution
    to the final measure. All data are also padded with a leading and trailing
    zero.

    The default data processing method, which keeps the total integral of the
    SRF equal to at least 99.9% of that in the raw data, might still yield a
    dataset with long tails with values close to zero with a very low
    contribution to the final result. The  data is regularly revisited and
    optimized based on feedback from the development team and users. We
    strongly advise users to visualize the SRF data before using them to make
    sure that the data are processed to their liking. If necessary, Eradiate
    ships an SRF processing toolbox
    (see :doc:`/tutorials/howto/srf_filtering/srf_filtering`).

    Raw data are also available, using a ``-raw`` suffix to the dataset ID
    (*e.g.* ``sentinel_3b-slstr-5-raw``).

``sentinel_2a-msi``
^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/sentinel_2a-msi-1.nc``
    * ``spectra/srf/sentinel_2a-msi-2.nc``
    * ``spectra/srf/sentinel_2a-msi-3.nc``
    * ``spectra/srf/sentinel_2a-msi-4.nc``
    * ``spectra/srf/sentinel_2a-msi-5.nc``
    * ``spectra/srf/sentinel_2a-msi-6.nc``
    * ``spectra/srf/sentinel_2a-msi-7.nc``
    * ``spectra/srf/sentinel_2a-msi-8.nc``
    * ``spectra/srf/sentinel_2a-msi-9.nc``
    * ``spectra/srf/sentinel_2a-msi-10.nc``
    * ``spectra/srf/sentinel_2a-msi-11.nc``
    * ``spectra/srf/sentinel_2a-msi-12.nc``
    * ``spectra/srf/sentinel_2a-msi-8a.nc``

.. image:: /fig/srf/sentinel_2a-msi.png

``sentinel_2b-msi``
^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/sentinel_2b-msi-1.nc``
    * ``spectra/srf/sentinel_2b-msi-2.nc``
    * ``spectra/srf/sentinel_2b-msi-3.nc``
    * ``spectra/srf/sentinel_2b-msi-4.nc``
    * ``spectra/srf/sentinel_2b-msi-5.nc``
    * ``spectra/srf/sentinel_2b-msi-6.nc``
    * ``spectra/srf/sentinel_2b-msi-7.nc``
    * ``spectra/srf/sentinel_2b-msi-8.nc``
    * ``spectra/srf/sentinel_2b-msi-9.nc``
    * ``spectra/srf/sentinel_2b-msi-10.nc``
    * ``spectra/srf/sentinel_2b-msi-11.nc``
    * ``spectra/srf/sentinel_2b-msi-12.nc``
    * ``spectra/srf/sentinel_2b-msi-8a.nc``

.. image:: /fig/srf/sentinel_2b-msi.png

``sentinel_3a-olci``
^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/sentinel_3a-olci-1.nc``
    * ``spectra/srf/sentinel_3a-olci-2.nc``
    * ``spectra/srf/sentinel_3a-olci-3.nc``
    * ``spectra/srf/sentinel_3a-olci-4.nc``
    * ``spectra/srf/sentinel_3a-olci-5.nc``
    * ``spectra/srf/sentinel_3a-olci-6.nc``
    * ``spectra/srf/sentinel_3a-olci-7.nc``
    * ``spectra/srf/sentinel_3a-olci-8.nc``
    * ``spectra/srf/sentinel_3a-olci-9.nc``
    * ``spectra/srf/sentinel_3a-olci-10.nc``
    * ``spectra/srf/sentinel_3a-olci-11.nc``
    * ``spectra/srf/sentinel_3a-olci-12.nc``
    * ``spectra/srf/sentinel_3a-olci-13.nc``
    * ``spectra/srf/sentinel_3a-olci-14.nc``
    * ``spectra/srf/sentinel_3a-olci-15.nc``
    * ``spectra/srf/sentinel_3a-olci-16.nc``
    * ``spectra/srf/sentinel_3a-olci-17.nc``
    * ``spectra/srf/sentinel_3a-olci-18.nc``
    * ``spectra/srf/sentinel_3a-olci-19.nc``
    * ``spectra/srf/sentinel_3a-olci-20.nc``
    * ``spectra/srf/sentinel_3a-olci-21.nc``

.. image:: /fig/srf/sentinel_3a-olci.png

``sentinel_3a-slstr``
^^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/sentinel_3a-slstr-1.nc``
    * ``spectra/srf/sentinel_3a-slstr-2.nc``
    * ``spectra/srf/sentinel_3a-slstr-3.nc``
    * ``spectra/srf/sentinel_3a-slstr-4.nc``
    * ``spectra/srf/sentinel_3a-slstr-5.nc``
    * ``spectra/srf/sentinel_3a-slstr-6.nc``
    * ``spectra/srf/sentinel_3a-slstr-7.nc``
    * ``spectra/srf/sentinel_3a-slstr-8.nc``
    * ``spectra/srf/sentinel_3a-slstr-9.nc``

.. image:: /fig/srf/sentinel_3a-slstr.png

``sentinel_3b-olci``
^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/sentinel_3b-olci-1.nc``
    * ``spectra/srf/sentinel_3b-olci-2.nc``
    * ``spectra/srf/sentinel_3b-olci-3.nc``
    * ``spectra/srf/sentinel_3b-olci-4.nc``
    * ``spectra/srf/sentinel_3b-olci-5.nc``
    * ``spectra/srf/sentinel_3b-olci-6.nc``
    * ``spectra/srf/sentinel_3b-olci-7.nc``
    * ``spectra/srf/sentinel_3b-olci-8.nc``
    * ``spectra/srf/sentinel_3b-olci-9.nc``
    * ``spectra/srf/sentinel_3b-olci-10.nc``
    * ``spectra/srf/sentinel_3b-olci-11.nc``
    * ``spectra/srf/sentinel_3b-olci-12.nc``
    * ``spectra/srf/sentinel_3b-olci-13.nc``
    * ``spectra/srf/sentinel_3b-olci-14.nc``
    * ``spectra/srf/sentinel_3b-olci-15.nc``
    * ``spectra/srf/sentinel_3b-olci-16.nc``
    * ``spectra/srf/sentinel_3b-olci-17.nc``
    * ``spectra/srf/sentinel_3b-olci-18.nc``
    * ``spectra/srf/sentinel_3b-olci-19.nc``
    * ``spectra/srf/sentinel_3b-olci-20.nc``
    * ``spectra/srf/sentinel_3b-olci-21.nc``

.. image:: /fig/srf/sentinel_3b-olci.png

``sentinel_3b-slstr``
^^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/sentinel_3b-slstr-1.nc``
    * ``spectra/srf/sentinel_3b-slstr-2.nc``
    * ``spectra/srf/sentinel_3b-slstr-3.nc``
    * ``spectra/srf/sentinel_3b-slstr-4.nc``
    * ``spectra/srf/sentinel_3b-slstr-5.nc``
    * ``spectra/srf/sentinel_3b-slstr-6.nc``
    * ``spectra/srf/sentinel_3b-slstr-7.nc``
    * ``spectra/srf/sentinel_3b-slstr-8.nc``
    * ``spectra/srf/sentinel_3b-slstr-9.nc``

.. image:: /fig/srf/sentinel_3b-slstr.png

``aqua-modis``
^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/aqua-modis-1.nc``
    * ``spectra/srf/aqua-modis-2.nc``
    * ``spectra/srf/aqua-modis-3.nc``
    * ``spectra/srf/aqua-modis-4.nc``
    * ``spectra/srf/aqua-modis-5.nc``
    * ``spectra/srf/aqua-modis-6.nc``
    * ``spectra/srf/aqua-modis-7.nc``
    * ``spectra/srf/aqua-modis-8.nc``
    * ``spectra/srf/aqua-modis-9.nc``
    * ``spectra/srf/aqua-modis-10.nc``
    * ``spectra/srf/aqua-modis-11.nc``
    * ``spectra/srf/aqua-modis-12.nc``
    * ``spectra/srf/aqua-modis-13.nc``
    * ``spectra/srf/aqua-modis-14.nc``
    * ``spectra/srf/aqua-modis-15.nc``
    * ``spectra/srf/aqua-modis-16.nc``

.. image:: /fig/srf/aqua-modis.png

``terra-modis``
^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/terra-modis-1.nc``
    * ``spectra/srf/terra-modis-2.nc``
    * ``spectra/srf/terra-modis-3.nc``
    * ``spectra/srf/terra-modis-4.nc``
    * ``spectra/srf/terra-modis-5.nc``
    * ``spectra/srf/terra-modis-6.nc``
    * ``spectra/srf/terra-modis-7.nc``
    * ``spectra/srf/terra-modis-8.nc``
    * ``spectra/srf/terra-modis-9.nc``
    * ``spectra/srf/terra-modis-10.nc``
    * ``spectra/srf/terra-modis-11.nc``
    * ``spectra/srf/terra-modis-12.nc``
    * ``spectra/srf/terra-modis-13.nc``
    * ``spectra/srf/terra-modis-14.nc``
    * ``spectra/srf/terra-modis-15.nc``
    * ``spectra/srf/terra-modis-16.nc``

.. image:: /fig/srf/terra-modis.png

``jpss1-viirs``
^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/jpss1-viirs-i1.nc``
    * ``spectra/srf/jpss1-viirs-i2.nc``
    * ``spectra/srf/jpss1-viirs-i3.nc``
    * ``spectra/srf/jpss1-viirs-i4.nc``
    * ``spectra/srf/jpss1-viirs-i5.nc``
    * ``spectra/srf/jpss1-viirs-m1.nc``
    * ``spectra/srf/jpss1-viirs-m2.nc``
    * ``spectra/srf/jpss1-viirs-m3.nc``
    * ``spectra/srf/jpss1-viirs-m4.nc``
    * ``spectra/srf/jpss1-viirs-m5.nc``
    * ``spectra/srf/jpss1-viirs-m6.nc``
    * ``spectra/srf/jpss1-viirs-m7.nc``
    * ``spectra/srf/jpss1-viirs-m8.nc``
    * ``spectra/srf/jpss1-viirs-m9.nc``
    * ``spectra/srf/jpss1-viirs-m10.nc``
    * ``spectra/srf/jpss1-viirs-m11.nc``
    * ``spectra/srf/jpss1-viirs-m12.nc``
    * ``spectra/srf/jpss1-viirs-m13.nc``
    * ``spectra/srf/jpss1-viirs-m14.nc``
    * ``spectra/srf/jpss1-viirs-m15.nc``
    * ``spectra/srf/jpss1-viirs-m16.nc``
    * ``spectra/srf/jpss1-viirs-m16a.nc``
    * ``spectra/srf/jpss1-viirs-m16b.nc``

.. image:: /fig/srf/jpss1-viirs.png

``npp-viirs``
^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/npp-viirs-i1.nc``
    * ``spectra/srf/npp-viirs-i2.nc``
    * ``spectra/srf/npp-viirs-i3.nc``
    * ``spectra/srf/npp-viirs-i4.nc``
    * ``spectra/srf/npp-viirs-i5.nc``
    * ``spectra/srf/npp-viirs-m1.nc``
    * ``spectra/srf/npp-viirs-m2.nc``
    * ``spectra/srf/npp-viirs-m3.nc``
    * ``spectra/srf/npp-viirs-m4.nc``
    * ``spectra/srf/npp-viirs-m5.nc``
    * ``spectra/srf/npp-viirs-m6.nc``
    * ``spectra/srf/npp-viirs-m7.nc``
    * ``spectra/srf/npp-viirs-m8.nc``
    * ``spectra/srf/npp-viirs-m9.nc``
    * ``spectra/srf/npp-viirs-m10.nc``
    * ``spectra/srf/npp-viirs-m11.nc``
    * ``spectra/srf/npp-viirs-m12.nc``
    * ``spectra/srf/npp-viirs-m13.nc``
    * ``spectra/srf/npp-viirs-m14.nc``
    * ``spectra/srf/npp-viirs-m15.nc``
    * ``spectra/srf/npp-viirs-m16a.nc``
    * ``spectra/srf/npp-viirs-m16b.nc``

.. image:: /fig/srf/npp-viirs.png

``metop_a-avhrr``
^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/metop_a-avhrr-1.nc``
    * ``spectra/srf/metop_a-avhrr-2.nc``
    * ``spectra/srf/metop_a-avhrr-3a.nc``
    * ``spectra/srf/metop_a-avhrr-3b.nc``
    * ``spectra/srf/metop_a-avhrr-4.nc``
    * ``spectra/srf/metop_a-avhrr-5.nc``

.. image:: /fig/srf/metop_a-avhrr.png

``metop_b-avhrr``
^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/metop_b-avhrr-1.nc``
    * ``spectra/srf/metop_b-avhrr-2.nc``
    * ``spectra/srf/metop_b-avhrr-3a.nc``
    * ``spectra/srf/metop_b-avhrr-3b.nc``
    * ``spectra/srf/metop_b-avhrr-4.nc``
    * ``spectra/srf/metop_b-avhrr-5.nc``

.. image:: /fig/srf/metop_b-avhrr.png

``metop_c-avhrr``
^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/metop_c-avhrr-1.nc``
    * ``spectra/srf/metop_c-avhrr-2.nc``
    * ``spectra/srf/metop_c-avhrr-3a.nc``
    * ``spectra/srf/metop_c-avhrr-3b.nc``
    * ``spectra/srf/metop_c-avhrr-4.nc``
    * ``spectra/srf/metop_c-avhrr-5.nc``

.. image:: /fig/srf/metop_c-avhrr.png

``metop_sg-metimage``
^^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/metop_sg-metimage-vii4.nc``
    * ``spectra/srf/metop_sg-metimage-vii8.nc``
    * ``spectra/srf/metop_sg-metimage-vii12.nc``
    * ``spectra/srf/metop_sg-metimage-vii15.nc``
    * ``spectra/srf/metop_sg-metimage-vii16.nc``
    * ``spectra/srf/metop_sg-metimage-vii17.nc``
    * ``spectra/srf/metop_sg-metimage-vii20.nc``
    * ``spectra/srf/metop_sg-metimage-vii22.nc``
    * ``spectra/srf/metop_sg-metimage-vii23.nc``
    * ``spectra/srf/metop_sg-metimage-vii24.nc``
    * ``spectra/srf/metop_sg-metimage-vii25.nc``
    * ``spectra/srf/metop_sg-metimage-vii26.nc``
    * ``spectra/srf/metop_sg-metimage-vii28.nc``
    * ``spectra/srf/metop_sg-metimage-vii30.nc``
    * ``spectra/srf/metop_sg-metimage-vii33.nc``
    * ``spectra/srf/metop_sg-metimage-vii34.nc``
    * ``spectra/srf/metop_sg-metimage-vii35.nc``
    * ``spectra/srf/metop_sg-metimage-vii37.nc``
    * ``spectra/srf/metop_sg-metimage-vii39.nc``
    * ``spectra/srf/metop_sg-metimage-vii40.nc``

.. image:: /fig/srf/metop_sg-metimage.png

``msg1-seviri``
^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/msg1-seviri-vis06.nc``
    * ``spectra/srf/msg1-seviri-vis08.nc``
    * ``spectra/srf/msg1-seviri-nir16.nc``
    * ``spectra/srf/msg1-seviri-hrv.nc``

.. image:: /fig/srf/msg1-seviri.png

``msg2-seviri``
^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/msg2-seviri-vis06.nc``
    * ``spectra/srf/msg2-seviri-vis08.nc``
    * ``spectra/srf/msg2-seviri-nir16.nc``
    * ``spectra/srf/msg2-seviri-hrv.nc``

.. image:: /fig/srf/msg2-seviri.png

``msg3-seviri``
^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/msg3-seviri-vis06.nc``
    * ``spectra/srf/msg3-seviri-vis08.nc``
    * ``spectra/srf/msg3-seviri-nir16.nc``
    * ``spectra/srf/msg3-seviri-hrv.nc``

.. image:: /fig/srf/msg3-seviri.png

``msg4-seviri``
^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/msg4-seviri-vis06.nc``
    * ``spectra/srf/msg4-seviri-vis08.nc``
    * ``spectra/srf/msg4-seviri-nir16.nc``
    * ``spectra/srf/msg4-seviri-hrv.nc``

.. image:: /fig/srf/msg4-seviri.png

``mtg_i-fci``
^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/mtg_i-fci-nir13.nc``
    * ``spectra/srf/mtg_i-fci-nir16.nc``
    * ``spectra/srf/mtg_i-fci-nir22.nc``
    * ``spectra/srf/mtg_i-fci-vis04.nc``
    * ``spectra/srf/mtg_i-fci-vis05.nc``
    * ``spectra/srf/mtg_i-fci-vis06.nc``
    * ``spectra/srf/mtg_i-fci-vis08.nc``
    * ``spectra/srf/mtg_i-fci-vis09.nc``

.. image:: /fig/srf/mtg_i-fci.png

``mtg_i-li``
^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/mtg_i-li-1.nc``
    * ``spectra/srf/mtg_i-li-2.nc``

.. image:: /fig/srf/mtg_i-li.png

``parasol-polder``
^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/parasol-polder-443.nc``
    * ``spectra/srf/parasol-polder-490.nc``
    * ``spectra/srf/parasol-polder-565.nc``
    * ``spectra/srf/parasol-polder-670.nc``
    * ``spectra/srf/parasol-polder-763.nc``
    * ``spectra/srf/parasol-polder-765.nc``
    * ``spectra/srf/parasol-polder-865.nc``
    * ``spectra/srf/parasol-polder-910.nc``
    * ``spectra/srf/parasol-polder-1020.nc``

.. image:: /fig/srf/parasol-polder.png

``proba_v-vegetation_left``
^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/proba_v-vegetation_left-blue.nc``
    * ``spectra/srf/proba_v-vegetation_left-red.nc``
    * ``spectra/srf/proba_v-vegetation_left-nir.nc``
    * ``spectra/srf/proba_v-vegetation_left-swir.nc``

.. image:: /fig/srf/proba_v-vegetation_left.png

``proba_v-vegetation_center``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/proba_v-vegetation_center-blue.nc``
    * ``spectra/srf/proba_v-vegetation_center-red.nc``
    * ``spectra/srf/proba_v-vegetation_center-nir.nc``
    * ``spectra/srf/proba_v-vegetation_center-swir.nc``

.. image:: /fig/srf/proba_v-vegetation_center.png

``proba_v-vegetation_right``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. dropdown:: Data store paths

    * ``spectra/srf/proba_v-vegetation_right-blue.nc``
    * ``spectra/srf/proba_v-vegetation_right-red.nc``
    * ``spectra/srf/proba_v-vegetation_right-nir.nc``
    * ``spectra/srf/proba_v-vegetation_right-swir.nc``

.. image:: /fig/srf/proba_v-vegetation_right.png