Fixes + add xrft, xmitgcm.

Author: dcherian

doc/faq.rst

@@ -166,12 +166,12 @@ They may be useful points of reference for your work:
 
 - `aospy <https://aospy.readthedocs.io>`_: Automated analysis and management of gridded climate data.
 - `eofs <https://ajdawson.github.io/eofs/>`_: EOF analysis in Python.
-- `MPAS-Analysis <http://mpas-analysis.readthedocs.io>`_: Analysis for simulations produced with Model for Prediction Across Scales (MPAS) components and the Accelerated Climate Model for Energy (ACME)
+- `MPAS-Analysis <http://mpas-analysis.readthedocs.io>`_: Analysis for simulations produced with Model for Prediction Across Scales (MPAS) components and the Accelerated Climate Model for Energy (ACME).
 - `psyplot <https://https://psyplot.readthedocs.io>`_: Interactive data visualization with python.
 - `PyGDX <https://pygdx.readthedocs.io/en/latest/>`_: Python 3 package for
   accessing data stored in GAMS Data eXchange (GDX) files. Also uses a custom
   subclass.
-- `salem <https://salem.readthedocs.io>`_: Adds geolocalised subsetting,
+- `salem <https://salem.readthedocs.io>`_: Adds geolocalised subsetting, masking, and plotting operations to xarray's data structures via accessors.
 - `sklearn-xarray (1) <https://phausamann.github.io/sklearn-xarray>`_: Combines scikit-learn and xarray (1).
 - `sklearn-xarray (2) <https://sklearn-xarray.readthedocs.io/en/latest/>`_: Combines scikit-learn and xarray (2).
 - `windspharm <https://ajdawson.github.io/windspharm/index.html>`_: Spherical
@@ -180,8 +180,10 @@ They may be useful points of reference for your work:
 - `xarray-topo <https://gitext.gfz-potsdam.de/sec55-public/xarray-topo>`_: xarray extension for topographic analysis and modelling.
 - `xbpch <https://github.com/darothen/xbpch>`_: xarray interface for bpch files.
 - `xESMF <https://xesmf.readthedocs.io>`_: Universal Regridder for Geospatial Data.
-- `xgcm <https://xgcm.readthedocs.io/>`_: General Circulation Model Postprocessing. Uses subclassing and custom xarray backends.
-- `xshape <https://xshape.readthedocs.io/>`_: Tools for working with shapefiles, topographies, and polygons in xarray
+- `xgcm <https://xgcm.readthedocs.io/>`_: Extends the xarray data model to understand finite volume grid cells (common in General Circulation Models) and provides interpolation and difference operations for such grids.
+- `xmitgcm <http://xgcm.readthedocs.io/>`_: a python package for reading `MITgcm <http://mitgcm.org/>`_ binary MDS files into xarray data structures.
+- `xrft <https://github.com/rabernat/xrft>`_: Fourier transforms for xarray data.
+- `xshape <https://xshape.readthedocs.io/>`_: Tools for working with shapefiles, topographies, and polygons in xarray.
 
 How should I cite xarray?
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