Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A simplified climate model and maximum entropy production   A simplified climate model based on maximum entropy production, described by
a variational principle, is revisited and an analytical solution to its
Euler-Lagrange equation is found. Mindful of controversy about maximum or
minimum entropy production in open thermodynamical systems, we show that the
solution extremizing the action integral corresponds to a maximum.

6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin