Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Elongation and stability of a linear dune   Compared to barchan dunes, the morphodynamics of linear dunes that elongate
on a non-erodible bed is barely investigated by means of laboratory experiments
or numerical simulations. Using a cellular automaton model, we study the
elongation of a solitary linear dune from a sand source and show that it can
reach a steady state. This steady state is analyzed to understand the physical
processes at work along the dune. Crest reversals together with avalanche
processes control the shape of transverse sections. Dune width and height
decrease almost linearly with distance downstream until the minimum size for
dunes. This is associated with a constant sand loss along the dune, which
eventually compensates for the sediment influx and sets the dune length. This
sand budget is discussed to distinguish an elongating linear dune from a
barchan dune and to explain the complexity of linear dune fields in nature.

5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg