  In this work, we report measurements of the height profile of transverse
dunes in the coastal dune field known as ``Len\c{c}\'ois Maranhenses'',
northeastern Brazil. Our measurements show that transverse dunes with
approximately the same height present a variable brink position relative to the
crest, in contrast to the case of barchan dunes. Based on our field data, we
present a relation for the dune spacing as a function of the crest-brink
distances of transverse dunes. Furthermore, we compare the measurements with
simulations of transverse dunes obtained from a two-dimensional dune model,
where a phenomenological definition is introduced for the length of the
separation streamlines on the lee side of closely spaced transverse dunes. We
find that our model reproduces transverse dune fields with similar inter-dune
distances and dune aspect ratios as measured in the field.
