Spatial and temporal dynamics of the urban heat island effect in a small Brazilian city

This study examined the spatial and temporal patterns of the canopy layer urban heat islands (UHI_UCL) in a small city in southeastern Brazil using the local climate zone (LCZ) system. We analysed the influence of weather conditions, LCZs characteristics, and local surface relief on the UHI_UCL magnitudes. Mobile traverses were used to measure air temperatures during representative nights of wet and dry seasons. Daily maximum magnitudes were observed in compact classes (LCZs 3 and 7) under ideal weather conditions (dry, clear skies, and calm) and higher anthropogenic heat release (weekdays). Seasonal effects on LCZ thermal differences were negligible. The peripheral landscapes were warmer than the city centre in both seasons. Among the warmer areas in the city, magnitudes in compact LCZs 3 and 7 were consistently higher than in LCZ 6. In general, representative sites of the main ‘built’ LCZs in the study area exhibit similar inter-zone temperature patterns to those reported for cities of different sizes from tropical and midlatitude regions. Thermal contrasts of ΔT_{LCZ 3 − D} in the study area reveal significant evidence that small cities can have as strong heat islands as bigger cities. These findings highlight the importance of the LCZ system to identify the main controlling factors driving such thermal differences and the need to extend the application of this approach in other South American cities to yield systematic data of UHI_UCL for urban planning given the coming challenges of climate change over the region.     

Peripheral creativity: temporary cultural uses as alternatives to inefficient policies?

ABSTRACT

The article focuses on temporary and improvised cultural spaces in marginalized neighbourhoods of Rio de Janeiro, Brazil. They are presented here as alternatives to current urban and cultural policies, often based on international ‘best practices’ models with exclusionary and segregating consequences. It begins with a brief overview into North American and Western European cultural planning policies. It then analyses the instability of cultural policies in Brazil, highlighting that, after a period of State recognition of bottom-up actions, administrators have turned to a contradictory planning scheme that mixes outdated and recent international trends, leading lower-income inhabitants to self-build their own cultural spaces. Unlike many products of today’s global strand of ‘tactic urbanism’, Rio’s temporary spaces are politically charged territories of resistance. An example is ‘Cine Taquara’ – an improvised cinema and debate forum that illustrates how, in an unequal city, such initiatives can do more towards social inclusion than ready-made models.     

The Radiocarbon Chronology of Southern Spain's Late Prehistory (5600–1000 cal BC): A Comparative Review

This paper is the first updated review of the scope, depth and problems related to the current radiocarbon chronology of the late prehistory of southern Iberia. The aim is twofold. First, it critically analyses the quantity and quality of radiocarbon dates used to interpret the diverse trajectories of western Mediterranean societies throughout more than four millennia. Secondly, it reviews a set of three different and prominent archaeological phenomena from an inter‐regional comparative perspective: primary and secondary burial practices, domestic stone architecture and ditched enclosures. Our long‐term, geographically wide‐ranging approach locates similarities while highlighting the effects of local and historical conditions in certain divergent circumstances.     

Asymmetric Encounters in Native Canada

Occasionally in recent decades, relations between the Canadian state and particular Native communities have spiralled into open confrontation and violence. While such instances reflect the failure of conciliatory or decolonizing politics within a liberal–democratic milieu, scholarship has barely begun to analyze these events in a systematic fashion. This article applies to long-standing questions about political behaviour to the study of Native-state relations in Canada. By this, the authors particularly mean the dynamics of Native peoples' mobilization and institutional engagement. Examining several recent cases of open confrontation, this article looks for the basic circumstances in which violence arises, and how confrontation alters internal political dynamics in Native communities.     

Archaeo-environmental study of the Almas river: mining pollution and the Cerrado biome in the end of the nineteenth century in Mid-Western,Brazil

This article proposes to understand the environmental impacts of a gold mining exploration in the Cerrado biome or Brazilian Savanna at the end of the nineteenth century in Mid-Western, Brazil. Firstly, the Cerrado biome is described according to perceptions about the ecological characteristics, ecological researches conducted, and mainly according to the ecosystem of the Pireneus mountains our area of research. Secondly, the historical mining impacts of nineteenth century are presented through reflections on the mining techniques of gold exploration, and through the environmental consequences of metal concentration in the area. Finally, the eco-archaeological study of the soil samples from the Almas river area in Mid-Western Brazil is demonstrated, as well as, the interpretation about the emergency of historical pollution patterns.