• Energy Research

Soil moisture induced droughts are expected to become more frequent under future global climate change. Precipitation has been previously assumed to be mainly responsible for variability in summer soil moisture. However, little is known about the impacts of precipitation frequency on summer soil moisture, either interannually or spatially. To better understand the temporal and spatial drivers of summer drought, 415 site yr measurements observed at 75 flux sites world wide were used to analyze the temporal and spatial relationships between summer soil water content (SWC) and the precipitation frequencies at various temporal scales, i.e., from half-hourly, 3, 6, 12 and 24 h measurements. Summer precipitation was found to be an indicator of interannual SWC variability with r of 0.49 (p < 0.001) for the overall dataset. However, interannual variability in summer SWC was also significantly correlated with the five precipitation frequencies and the sub-daily precipitation frequencies seemed to explain the interannual SWC variability better than the total of precipitation. Spatially, all these precipitation frequencies were better indicators of summer SWC than precipitation totals, but these better performances were only observed in non-forest ecosystems. Our results demonstrate that precipitation frequency may play an important role in regulating both interannual and spatial variations of summer SWC, which has probably been overlooked or underestimated. However, the spatial interpretation should carefully consider other factors, such as the plant functional types and soil characteristics of diverse ecoregions.

An orchard carbon fixation between 5-11 mmol m-2 s-1 has been recorded through eddy covariance technique during the summer for a table grape in Southern Italy. The total daily ecosystem exchange was equal to 2.07 g C/m2 day in 2001, and 1.68 in the warmer 2002. The latent heat of evapotranspiration was 40% Rn in 2001 and about 30% in 2002. Eddy covariance allowed to have information on the water use efficiency (WUE) of the vineyard during the two years, that was, at midday, equal to 0.0012 in 2001 and 0.0015 in 2002. WUE, determined at canopy scale, is very important mainly in those environments where water is a limiting factor and a correct irrigation schedule is necessary.

In 2019, the World Meteorological Organization published its “Guidance on Integrated Urban Hydrometeorological, Climate and Environment Services (Volume I: Concept and Methodology)” to assist WMO Members in developing and implementing the urban services that address the needs of city stakeholders in their countries. The guidance has relevant implications for not only protecting infrastructures from the impacts of climate change in the urban environment, but its proper declination strongly supports health-related policies to protect the population from direct and indirect impacts. Utilizing some principles of the guidance, the urbanized area of Bologna (Italy) was analyzed in order to furnish the municipality with tools coherent with the best practices actually emerging from the international bibliography to protect the citizens’ health of this city. Specifically, the analysis concentrated on the public spaces and the potential vulnerabilities of the fragile population to high-temperature regimes in the city. Utilizing the guidance as a methodological framework, the authors developed a methodology to define the microclimate vulnerabilities of the city and specific cards to assist the policymakers in city regeneration. Because the medieval structure of the city does not allow the application of a wide set of nature-based solutions, our main attention was placed on the possibility of furnishing the city with a great number of pocket parks obtainable from spaces actually dedicated to parking lots, thus introducing new green infrastructures in a highly deprived area in order to assure safety spaces for the fragile population.

While a substantial reduction of GHG (greenhouse gases) is urged, large-scale mitigation implies a detailed and holistic knowledge on the role of specific cropping systems, including the effect of management choices and local factors on the final balance between emissions and removals, this last typical of cropping systems. Here, a conventionally managed irrigated kiwifruit orchard has been studied to assess its greenhouse gases emissions and removals to determine its potential action as a C sink or, alternately, as a C source. The paper integrates two independent approaches. Biological CO2 fluxes have been monitored during 2012 using the micrometeorological Eddy covariance technique, while life cycle assessment quantified emissions derived from the energy and material used. In a climatic-standard year, total GHG emitted as consequence of the management were 4.25 t CO2-eq−1 ha−1 yr−1 while the net uptake measured during the active vegetation phase was as high as 4.9 t CO2 ha−1 yr−1. This led to a positive contribution of the crop to CO2 absorption, with a 1.15 efficiency ratio (sink-source factor defined as t CO2 stored/t CO2 emitted). The mitigating activity, however, completely reversed under extremely unfavorable climatic conditions, such as those recorded in 2003, when the efficiency ratio became 0.91, demonstrating that the occurrence of hotter and drier conditions are able to compromise the capability of Actinidia to offset the GHG emissions, also under appropriate irrigation.

Various environmental factors influence the outbreak and spread of epidemic or even pandemic events which, in turn, may cause feedbacks on the environment. The novel coronavirus disease (COVID-19) was declared a pandemic on 13 March 2020 and its rapid onset, spatial extent and complex consequences make it a once-in-a-century global disaster. Most countries responded by social distancing measures and severely diminished economic and other activities. Consequently, by the end of April 2020, the COVID-19 pandemic has led to numerous environmental impacts, both positive such as enhanced air and water quality in urban areas, and negative, such as shoreline pollution due to the disposal of sanitary consumables. This study presents an early overview of the observed and potential impacts of the COVID-19 on the environment. We argue that the effects of COVID-19 are determined mainly by anthropogenic factors which are becoming obvious as human activity diminishes across the planet, and the impacts on cities and public health will be continued in the coming years.

The purpose of this paper is to describe the process of building a coherent frame for the identification of local environmental urban vulnerabilities, coping with heat waves’ increasing threats, and adopting specific adaptation policies in the Emilia-Romagna region. A microclimate model (ENVI-met) was used to simulate temperature regimes in five areas of Bologna, providing ex ante maps enabling us to locate the most vulnerable areas. Adaptation measures were suggested with the support of WMO Guidance 1234 and included recommendations about the introduction of high-albedo building materials and nature-based solutions. The step-by-step methodology developed, coupling local vulnerabilities with adaptation recommendation, integrates a scientific methodology into a political decision. The results, allowing us to widely represent this city’s vulnerability, are considered outstanding with respect to supporting the city’s adaptation ambitions and are now part of the running Bologna General Urban Plan (PUG), which regulates building interventions, introducing the obligation for enterprises to respect or ameliorate the microclimate in all the areas in which they intervene. This tool can be replicated and adapted to any municipal area, as it integrates authoritative WMO solutions with accurate microclimate assessment, thus providing locally tailored adaptation interventions. This paper aims to support the vision, shared by both science and policy makers, of transforming cities into widely resilient systems.