def concat_dim(cls, datasets, dim, vdims):
        """
        Concatenates datasets along one dimension
        """
        import iris
        from iris.experimental.equalise_cubes import equalise_attributes

        cubes = []
        for c, cube in datasets.items():
            cube = cube.copy()
            cube.add_aux_coord(iris.coords.DimCoord([c], var_name=dim.name))
            cubes.append(cube)
        cubes = iris.cube.CubeList(cubes)
        equalise_attributes(cubes)
        return cubes.merge_cube()
Concatenates datasets along one dimension