Estimating seasonal variations in cloud droplet number concentration over the boreal forest from satellite observations

Seasonal variations in cloud droplet number concentration (NCD) in low-level stratiform clouds over the boreal forest are estimated from MODIS observations of cloud optical and microphysical properties, using a sub-adiabatic cloud model to interpret vertical profiles of cloud properties. An uncertainty analysis of the cloud model is included to reveal the main sensitivities of the cloud model. We compared the seasonal cycle in NCD, obtained using 9 yr of satellite data, to surface concentrations of potential cloud activating aerosols, measured at the SMEAR II station at Hyytiälä in Finland. The results show that NCD and cloud condensation nuclei (CCN) concentrations have no clear correlation at seasonal time scale. The fraction of aerosols that actually activate as cloud droplet decreases sharply with increasing aerosol concentrations. Furthermore, information on the stability of the atmosphere shows that low NCD is linked to stable atmospheric conditions. Combining these findings leads to the conclusion that cloud droplet activation for the studied clouds over the boreal forest is limited by convection. Our results suggest that it is important to take the strength of convection into account when studying the influence of aerosols from the boreal forest on cloud formation, although they do not rule out the possibility that aerosols from the boreal forest affect other types of clouds with a closer coupling to the surfac

Targeting energy savings? Better on primary than final energy and less on intensity metrics

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGA eficiencia enerxética é un tema crítico nas políticas públicas, xa que é a clave para desvincular o crecemento económico e o uso da enerxía. Estes obxectivos están a ser aínda máis relevantes para abordar a crise enerxética e os novos escenarios xeopolíticos da guerra de Ucraína. Aínda que varios traballos analizaron os obxectivos de eficiencia enerxética, este traballo céntrase nos obxectivos de aforro enerxético, que representan a principal métrica de eficiencia para a Unión Europea. Este traballo enche un baleiro na literatura ao analizar os impactos económicos e ambientais da consecución de obxectivos de eficiencia enerxética mediante unha política fiscal enerxética, simulada por un modelo de equilibrio xeral computable híbrido con gran detalle tecnolóxico. Defínense seis escenarios para o aforro enerxético no consumo dos produtos enerxéticos, utilizando Portugal como caso de estudo. Os resultados relevantes para os responsables políticos dos escenarios simulados inclúen: (i) acadar obxectivos de aforro enerxético por medios alternativos, é dicir, dirixidos ao consumo de enerxía primaria ou final, proporcionar impactos heteroxéneos na eficiencia do sistema enerxético e no PIB, e algúns inesperados e indesexables nos impactos ambientais; (ii) unha fiscalidade relativamente máis baixa de todos os produtos enerxéticos produce impactos máis grandes e máis distorsionadores na xeración de electricidade que impostos máis elevados só sobre os combustibles fósiles (un resultado contraintuitivo), (iii) as políticas destinadas a reducir a enerxía primaria en lugar da enerxía final proporcionan os mellores resultados (maiores aumentos da eficiencia do sistema enerxético con impactos económicos máis suaves), o que vai en contra do principio da directiva europea sobre impostos enerxéticos pola que deben gravarse os produtos finais, independentemente dos insumos utilizados na súa produción e (iv) e os obxectivos non deben elaborarse en base a indicadores de intensidade enerxética. Polo tanto, móstrase que o tamaño dos impactos no balance entre as preocupacións económicas e ambientais depende do foco no aforro enerxético: de onde (consumo de enerxía primaria ou final) e a que (fósiles ou todos os produtos enerxéticos) sexa aplicado.Energy efficiency is a critical issue in public policies, as it is the key to decoupling economic growth and energy use. These objectives are becoming even more relevant to addressing the energy crisis and the new geopolitical scenarios delivered by the Ukraine war. Although several papers have analyzed energy efficiency goals, this paper focuses on energy savings targets, which represent the main efficiency metric for the European Union. This paper fills a gap in literature by analyzing the economic and environmental impacts of attaining energy efficiency targets through an energy fiscal policy, simulated by a hybrid computable general equilibrium model with technological detail. Six scenarios are defined for energy savings in primary/final energy consumption of fossil-fueled/all energy products, using Portugal as a case study. Relevant insights for policy makers from the simulated scenarios include: (i) achieving energy saving targets by alternative means, i.e., directed at primary or final energy consumption, provide heterogeneous impacts on the efficiency of the energy system and GDP, and some unexpected and undesirable outcomes concerning environmental impacts; (ii) a relatively lower taxation of all energy products deliver larger and more distorting impacts on electricity generation than higher taxes on fossil fuels only (a counterintuitive result), (iii) policies aiming to reduce primary energy instead of final energy provide the best outcomes (further increases in the efficiency of the energy system with smoother economic impacts), thereby pointing against the European Energy Taxation directive principle that taxation should be levied on final products, regardless of inputs used in their production and (iv) and targets should not be set up based on energy intensity indicators. Hence, it is shown that the size of the trade-off between economic and environmental concerns depends on where (primary or final energy consumption) and what (fossil or all energy products) energy savings are targeted.Fundação para a Ciência e a Tecnologia | Ref. UIDB/05037/2020Fundação para a Ciência e a Tecnologia | Ref. UIDP/05037/2020Fundação para a Ciência e a Tecnologia | Ref. UID/04085/2020Ministerio de Ciencia y Educación | Ref. PID2019-106677GB-I00Xunta de Galicia | Ref. GRC2017/063Universidade de Vigo/CISU

An integrated physical and cost-benefit approach to assess groins as a coastal erosion mitigation strategy

Future investments required for the construction and maintenance of coastal defense interventions are expected to increase, due to increasing coastal erosion issues along social, environmental and economically valuable coastal areas. The high costs related with coastal defense interventions require improved knowledge on their performance, considering impacts, costs and benefits. Despite the existence of several cost-benefit approaches applied to coastal zones, in this study a well-defined, sequential and integrated methodology supported by already existent numerical models is developed and applied to assess the effectiveness (shoreline evolution impacts), costs and benefits of different coastal defense interventions. This methodology encompasses three integrated modules, including a shoreline evolution module (to estimate areas of territory maintained, gained or lost over time), a coastal structure pre-design module (to estimate material volumes of coastal works) and a cost-benefit evaluation module (to assess cost-benefit evaluation criteria). The approach allows for the physical and economic comparison of different coastal defense intervention scenarios, helping coastal management and planning entities to define strategies. In this study, the proposed methodology was applied to evaluate the performance of different groin scenarios, based on a hypothetical case study. The case study allowed highlighting the importance of the physical and economic analysis of different scenarios. Results show that the definition of coastal defense interventions is complex where, on the one hand, best physical solutions are sometimes related to very high costs and, on the other hand, best economic scenarios lead to high territory losses. Thus, the innovative approach presented in this study shows that an integrated analysis of shoreline evolution, coastal intervention design and subsequent costs and benefits allows to improve the physical and economic performances of coastal defense interventions.publishe

The 30-year TAMSAT African rainfall climatology and time-series (TARCAT) dataset

African societies are dependent on rainfall for agricultural and other water-dependent activities, yet rainfall is extremely variable in both space and time and reoccurring water shocks, such as drought, can have considerable social and economic impacts. To help improve our knowledge of the rainfall climate, we have constructed a 30-year (1983–2012), temporally consistent rainfall dataset for Africa known as TARCAT (TAMSAT African Rainfall Climatology And Time-series) using archived Meteosat thermal infra-red (TIR) imagery, calibrated against rain gauge records collated from numerous African agencies. TARCAT has been produced at 10-day (dekad) scale at a spatial resolution of 0.0375°. An intercomparison of TARCAT from 1983 to 2010 with six long-term precipitation datasets indicates that TARCAT replicates the spatial and seasonal rainfall patterns and interannual variability well, with correlation coefficients of 0.85 and 0.70 with the Climate Research Unit (CRU) and Global Precipitation Climatology Centre (GPCC) gridded-gauge analyses respectively in the interannual variability of the Africa-wide mean monthly rainfall. The design of the algorithm for drought monitoring leads to TARCAT underestimating the Africa-wide mean annual rainfall on average by −0.37 mm day−1 (21%) compared to other datasets. As the TARCAT rainfall estimates are historically calibrated across large climatically homogeneous regions, the data can provide users with robust estimates of climate related risk, even in regions where gauge records are inconsistent in time

Knowledge and social capacity building for sustainable urban transformation

No abstract available

Evaluating the Impact of Nature-Based Solutions: A Handbook for Practitioners

The Handbook aims to provide decision-makers with a comprehensive NBS impact assessment framework, and a robust set of indicators and methodologies to assess impacts of nature-based solutions across 12 societal challenge areas: Climate Resilience; Water Management; Natural and Climate Hazards; Green Space Management; Biodiversity; Air Quality; Place Regeneration; Knowledge and Social Capacity Building for Sustainable Urban Transformation; Participatory Planning and Governance; Social Justice and Social Cohesion; Health and Well-being; New Economic Opportunities and Green Jobs. Indicators have been developed collaboratively by representatives of 17 individual EU-funded NBS projects and collaborating institutions such as the EEA and JRC, as part of the European Taskforce for NBS Impact Assessment, with the four-fold objective of: serving as a reference for relevant EU policies and activities; orient urban practitioners in developing robust impact evaluation frameworks for nature-based solutions at different scales; expand upon the pioneering work of the EKLIPSE framework by providing a comprehensive set of indicators and methodologies; and build the European evidence base regarding NBS impacts. They reflect the state of the art in current scientific research on impacts of nature-based solutions and valid and standardized methods of assessment, as well as the state of play in urban implementation of evaluation frameworks

Assessment of coastal management options by means of multilayered ecosystem models

This paper presents a multilayered ecosystem modelling approach that combines the simulation of the biogeochemistry of a coastal ecosystem with the simulation of the main forcing functions, such as catchment loading and aquaculture activities. This approach was developed as a tool for sustainable management of coastal ecosystems. A key feature is to simulate management scenarios that account for changes in multiple uses and enable assessment of cumulative impacts of coastal activities. The model was applied to a coastal zone in China with large aquaculture production and multiple catchment uses, and where management efforts to improve water quality are under way. Development scenarios designed in conjunction with local managers and aquaculture producers include the reduction of fish cages and treatment of wastewater. Despite the reduction in nutrient loading simulated in three different scenarios, inorganic nutrient concentrations in the bay were predicted to exceed the thresholds for poor quality defined by Chinese seawater quality legislation. For all scenarios there is still a Moderate High to High nutrient loading from the catchment, so further reductions might be enacted, together with additional decreases in fish cage culture. The model predicts that overall, shellfish production decreases by 10%–28% using any of these development scenarios, principally because shellfish growth is being sustained by the substances to be reduced for improvement of water quality. The model outcomes indicate that this may be counteracted by zoning of shellfish aquaculture at the ecosystem level in order to optimize trade-offs between productivity and environmental effects. The present case study exemplifies the value of multilayered ecosystem modelling as a tool for Integrated Coastal Zone Management and for the adoption of ecosystem approaches for marine resource management. This modelling approach can be applied worldwide, and may be particularly useful for the application of coastal management regulation, for instance in the implementation of the European Marine Strategy Framework Directive

Water management

No abstract available