Point Cloud Compression: Impact on Object Detection in Outdoor Contexts.

Increasing demand for more reliable and safe autonomous driving means that data involved in the various aspects of perception, such as object detection, will become more granular as the number and resolution of sensors progress. Using these data for on-the-fly object detection causes problems related to the computational complexity of onboard processing in autonomous vehicles, leading to a desire to offload computation to roadside infrastructure using vehicle-to-infrastructure communication links. The need to transmit sensor data also arises in the context of vehicle fleets exchanging sensor data, over vehicle-to-vehicle communication links. Some types of sensor data modalities, such as Light Detection and Ranging (LiDAR) point clouds, are so voluminous that their transmission is impractical without data compression. With most emerging autonomous driving implementations being anchored on point cloud data, we propose to evaluate the impact of point cloud compression on object detection. To that end, two different object detection architectures are evaluated using point clouds from the KITTI object dataset: raw point clouds and point clouds compressed with a state-of-the-art encoder and three different compression levels. The analysis is extended to the impact of compression on depth maps generated from images projected from the point clouds, with two conversion methods tested. Results show that low-to-medium levels of compression do not have a major impact on object detection performance, especially for larger objects. Results also show that the impact of point cloud compression is lower when detecting objects using depth maps, placing this particular method of point cloud data representation on a competitive footing compared to raw point cloud data.

Looking into individual choices and local realities to define adaptation options to drought and climate change.

Climate change adaptation choices defined by local communities reflect individual risk perception and contextual factors. This study examines how local contextual environmental factors contribute to individual choices for adapting to water scarcity in three locations in central Spain. The study evaluates citizens' choices by audience segmentation and explore the role of geographical location in segments' engagement with adaptation and adaptation measure preference. The results of the analysis of the effect of local experience support the findings of other studies that suggest that local experience is linked to risk perception but does not necessarily drive adaptive behaviour. The results suggest that respondents from most degraded areas show a higher local risk perception, but do not show homogeneous commitment to adaptation. The results also indicate differences over adaptation measure preferences across locations. Respondents of less degraded areas have a lower risk perception and show individualistic responses as compared to respondents in water stressed communities. These results highlight the relevance of local experience-driven risk perception in support to adaptation actions. Spain exemplifies many countries in southern Europe and North Africa, where drought is already a challenge to society and it is affecting an increasing number of people.

Vineyards in transition: A global assessment of the adaptation needs of grape producing regions under climate change.

This paper suggests how climate change may transform vineyards. We consider changes in agro-climatic indicators derived from climatic variables as drivers for adaptation needs. We use two climate scenarios, GCM GFL-ESM2M and HadGEM2-ES, with 0.5° spatial resolution and daily time step forced by two emission scenarios, RCP2.6 and 6.0, to estimate the transition of potential vineyards in the major grape production world areas by the late 21st century. We present and discuss changes in three impact indicators - one drought indicator and two temperature ones - aimed at exploring the benefits of transition-based policies. The drought indicator provides insights to prepare adaptation for extreme events in probabilistic terms. The temperature indicators offer information on the transition towards suitable zones of production. Future projections suggest a lack of water to maintain current levels of production in all regions of the world. Furthermore, thermal suitability of grapevine may be greatly affected in China and the Mediterranean region. Nevertheless, the possibility of quality wines is not altered within the regions with adequate suitability. Lastly, a portfolio of strategies to adapt to the future climate is presented.

Strategies to reduce water stress in Euro-Mediterranean river basins.

A portfolio of water management strategies now exists to contribute to reach water demand and supply targets. Among them, integrated water resource management has a large potential for reducing water disagreement in water scarcity regions. Many of the strategies are based on well tested choices and technical know-how, with proven benefits for users and environment. This paper considers water management practices that may contribute to reduce disagreement in water scarcity areas, evaluating the management alternatives in the Mediterranean basins of Europe, a region that exemplifies other water scarcity regions in the world. First, we use a model to compute water availability taking into account water management, temporal heterogeneity, spatial heterogeneity and policy options, and then apply this model across 396 river basins. Second, we use a wedge approach to illustrate policy choices for selected river basins: Thrace (Greece), Guadalquivir, Ebro, Tagus and Duero (Spain), Po (Italy) and Rhone (France). At the wide geographical level, the results show the multi-determinant complexities of climate change impacts and adaptation measures and the geographic nature of water resources and vulnerability metrics. At the local level, the results show that optimisation of water management is the dominating strategy for defining adaptation pathways. Results also show great sensitivity to ecological flow provision, suggesting that better attention should be paid to defining methods to estimate minimum ecological flows in water scarcity regions. For all scales, average water resource vulnerability computed by traditional vulnerability indicators may not be the most appropriate measure to inform climate change adaptation policy. This has large implications to applied water resource studies aiming to derive policy choices, and it is especially interesting in basins facing water scarcity. Our research aims to contribute to shape realistic water management options at the regional level and therefore provide information to climate change, agricultural and water policies.

Physical and economic consequences of climate change in Europe.

Quantitative estimates of the economic damages of climate change usually are based on aggregate relationships linking average temperature change to loss in gross domestic product (GDP). However, there is a clear need for further detail in the regional and sectoral dimensions of impact assessments to design and prioritize adaptation strategies. New developments in regional climate modeling and physical-impact modeling in Europe allow a better exploration of those dimensions. This article quantifies the potential consequences of climate change in Europe in four market impact categories (agriculture, river floods, coastal areas, and tourism) and one nonmarket impact (human health). The methodology integrates a set of coherent, high-resolution climate change projections and physical models into an economic modeling framework. We find that if the climate of the 2080s were to occur today, the annual loss in household welfare in the European Union (EU) resulting from the four market impacts would range between 0.2-1%. If the welfare loss is assumed to be constant over time, climate change may halve the EU's annual welfare growth. Scenarios with warmer temperatures and a higher rise in sea level result in more severe economic damage. However, the results show that there are large variations across European regions. Southern Europe, the British Isles, and Central Europe North appear most sensitive to climate change. Northern Europe, on the other hand, is the only region with net economic benefits, driven mainly by the positive effects on agriculture. Coastal systems, agriculture, and river flooding are the most important of the four market impacts assessed.

Drought risk management in Mediterranean river basins.

The Mediterranean region has an extensive hydraulic infrastructure and complex socioeconomic interactions among water users. In this region, competition for water among urban, agricultural, industrial, and environmental demands is strongest in times of water scarcity. Allocation of scarce water in the face of multiple demands is a challenging task that requires careful analysis. Precipitation decreases may likely be translated into drought periods in most cases. Nevertheless water scarcity (the shortage of water resources to serve water demands) not only depends on drought or precipitation deficits but also on water management. Adaptation options depend on the strategic contingency planning and management decisions that affect water resources systems. The risk management of water scarcity and drought depends on the level of water scarcity. Therefore, an adequate diagnosis of the water scarcity level is essential to anticipate the possible solutions. This study proposes a methodology for drought risk management based on the evaluation of 4 indicators of water scarcity to be used to define the thresholds of risk management actions. Based on the definition of thresholds, the study proposes the implementation of risk management actions that may be used for responding to each water scarcity situation.