Abstract. We study the so-called damped Navier-Stokes equations in the whole 2D space. The global well-posedness, dissipativity and further regularity of weak solutions of this problem in the uniformly-local spaces are verified based on the further development of the weighted energy theory for the Navier-Stokes type problems. Note that any divergent free vector field u0 ∈ L ∞ (R 2 ) is allowed and no assumptions on the spatial decay of solutions as |x| → ∞ are posed. In addition, applying the developed theory to the case of the classical Navier-Stokes problem in R 2 , we show that the properly defined weak solution can grow at most polynomially (as a quintic polynomial) as time goes to infinity. We study the following damped Navier-Stokes system in the whole space x ∈ R 2 :where α is a positive parameter. These equations describe, for instance, a 2-dimensional viscous liquid moving on a rough surface and are used in geophysical models for large-scale processes in atmosphere and ocean. The term αu parameterizes the extra dissipation occurring in the planetary boundary layer (see, e.g.,
Ped79[15]; see also
BP06[3] for the alternative source of damped Euler equations).The mathematical theory of damped Navier-Stokes and Euler equations is of a big current interest, see CV08,CVZ11,CR07,Il91,IlT06,IMT04 [4,5,6,10,11,12] and references therein. However, most part of these papers study either the case of bounded underlying domain (e.g., with periodic boundary conditions) or the 2000 Mathematics Subject Classification. 35Q30,35Q35.