Compressible primitive equation: formal derivation and stability of weak solutions

We present a formal derivation of a simplified version of Compressible Primitive Equations (CPEs) for atmosphere modeling. They are obtained from $3$-D compressible Navier-Stokes equations with an \emph{anisotropic viscous stress tensor} where viscosity depends on the density. We then study the stability of the weak solutions of this model by using an intermediate model, called model problem, which is more simple and practical, to achieve the main result

Agricultura e biodiversidade nas ciências sociais brasileiras: alimentando a comunicação entre ciência e políticas públicas.

O presente artigo decorre de uma reflexão sustentada em dois pressupostos: a) que as ciências e, em particular, as sociais, podem contribuir para informar as tomadas de decisão e a formulação de políticas públicas visando a melhoria da vida das pessoas no planeta e b) que o papel da agricultura na conservação da biodiversidade é uma questão atual de extrema relevância e que merece ser aprofundada. A relação entre a agricultura e a biodiversidade tem sido objeto de questionamentos recentes na sociedade e no campo das políticas públicas. Contudo, se os estudos relacionados à biodiversidade e à agricultura, separadamente, têm observado um considerável crescimento no Brasil, poucos são os investimentos de pesquisa sobre a relação entre esses dois grandes temas. A partir dessas considerações, seguimos dois objetivos principais: 1) investigar como o papel da agricultura familiar na preservação da biodiversidade tem sido abordado pelas Ciências Sociais no Brasil, particularmente nos artigos publicados em periódicos brasileiros nos últimos 20 anos; 2) testar uma metodologia de revisão bibliográfica, criteriosa, que possa ser útil aos tomadores de decisão em políticas públicas e demais interessados

Combining remote sensing and household level data for regional scale analysis of land cover change in the Brazilian Amazon

Land cover change in the Brazilian Amazon depends on the spatial variability of political, socioeconomic and biophysical factors, as well as on the land use history and its actors. A regional scale analysis was made in Rondônia State to identify possible differences in land cover change connected to spatial policies of land occupation, size and year of establishment of properties, accessibility measures and soil fertility. The analysis was made based on remote sensing data and household level data gathered with a questionnaire. Both types of analyses indicate that the highest level of total deforestation is found inside agrarian projects, especially in those established more than 20 years ago. Even though deforestation rates are similar inside and outside official settlements, inside agrarian projects forest depletion can exceed 50% at the property level within 10–14 years after establishment. The data indicate that both small-scale and medium to large-scale farmers contribute to deforestation processes in Rondônia State encouraged by spatial policies of land occupation, which provide better accessibility to forest fringes where soil fertility and forest resources are important determinants of location choic

Unsettling resettlements:Community, belonging and livelihood in Rio de Janeiro’s Minha Casa Minha Vida

This chapter argues that looking at forced evictions through the lens of housing resettlement or relocation can challenge the common-sense notion of temporal finality associated to enforced displacements—opening the latter up to a broader framework that recognises continuity across space and time. It focuses on the experiences of post-eviction state-led resettlements in 2 Minha Casa Minha Vida (MCMV) housing projects in Rio de Janeiro, Brazil, and attends to the relationship between those processes, community life and livelihoods—understood here not only as work, but also as the ability to sustain and flourish in life. In considering the everyday emotional, geographic, material and economic dimensions of post-eviction housing resettlements, as experienced by residents, these sites reveal enduring histories of urban insecurity and inequality that can, amongst other effects, reproduce and intensify gendered social structures

Nonlinear excitation of zonal flows by Rossby wave turbulence

We apply the wave-kinetic approach to study nonlinearly coupled Rossby wave-zonal flow fluid turbulence in a two-dimensional rotating fluid. Specifically, we consider for the first time nonlinear excitations of zonal flows by a broad spectrum of Rossby wave turbulence. Short-wavelength Rossby waves are described here as a fluid of quasi-particles, and are referred to as the 'Rossbyons'. It is shown that Reynolds stresses of Rossbyons can generate large-scale zonal flows. The result should be useful in understanding the origin of large-scale planetary and near-Earth atmospheric circulations. It also provides an example of a turbulent wave background driving a coherent structure