Role Of Natural Processes Research Articles

Extreme weather exacerbates ozone pollution in the Pearl River Delta, China: role of natural processes

Abstract. Ozone (O3) pollution research and management in China have mainly focused on anthropogenic emissions, while the importance of natural processes is often overlooked. With the increasing frequency of extreme weather events, the role of natural processes in exacerbating O3 pollution is gaining attention. In September 2022, the Pearl River Delta (PRD) in southern China experienced an extended period (25 d) of regional O3 exceedances and high temperatures (second highest over last 2 decades) due to extreme weather conditions influenced by the subtropical high and typhoon peripheries. Employing an integrated approach involving field measurements, machine learning and numerical model simulations, we investigated the impact of weather-induced natural processes on O3 pollution by considering meteorological factors, natural emissions, chemistry pathways and atmospheric transport. The hot weather intensified the emission of biogenic volatile organic compounds (BVOCs) by ∼10 %. Isoprene and biogenic formaldehyde accounted for 47 % of the in situ O3 production, underscoring the predominant role of BVOC emissions in natural processes. The chemical pathway of isoprene contributing to O3 formation was further explored, with O3 production more attributable to the further degradation of early generation isoprene oxidation products (contributed 64.5 %) than the direct isoprene oxidation itself (contributed 35.5 %). Besides, it was found that the hot weather significantly promoted regional photochemical reactions, with meteorological factors contributing to an additional 10.8 ppb of O3 levels compared to normal conditions. Temperature was identified as the dominant meteorological factor. Furthermore, the typhoon nearing landfall significantly enhanced the cross-regional transport of O3 from northern to southern China through stratosphere–troposphere exchange (STE). The CAM-Chem model simulations revealed that the STE-induced O3 on the PRD surface could reach a maximum of ∼8 ppb, highlighting the non-negligible impact of STE. This study highlights the importance of natural processes exacerbated by extreme weather events in O3 pollution and provides valuable insights into O3 pollution control under global warming.

Beach Monitoring and Morphological Response in the Presence of Coastal Defense Strategies at Riccione (Italy)

The coastal area at Riccione, in the southern Emilia-Romagna littoral region, is exposed to erosive processes, which are expected to be enhanced by climate change. The beach, mostly composed of fine sand, is maintained through various defense strategies, including frequent nourishment interventions for balancing the sediment deficit and other experimental solutions for reducing coastal erosion. Artificial reshaping of the beach and “common practices” in the sediment management redefine the beach morphology and the sediment redistribution almost continuously. These activities overlap each other and with the coastal dynamics, and this makes it very difficult to evaluate their effectiveness, as well as the role of natural processes on the beach morphological evolution. Topo-bathymetric and sedimentological monitoring of the beach has been carried out on a regular basis since 2000 by the Regional Agency for Prevention, Environment and Energy of Emilia-Romagna (Arpae). Further monitoring of the emerged and submerged beach has been carried out in 2019–2021 in the framework of the research project STIMARE, focusing on innovative strategies for coastal monitoring in relation with erosion risk. The aim of this study is to assess the coastal behavior at the interannual/seasonal scale in the southern coastal stretch of Riccione, where the adopted coastal defense strategies and management actions mostly control the morphological variations in the emerged and submerged beach besides the wave and current regime. The topo-bathymetric variations and erosion/accretion patterns provided by multitemporal monitoring have been related to natural processes and to anthropogenic activities. The morphological variations have been also assessed in volumetric terms in the different subzones of the beach, with the aim of better understanding the onshore/offshore sediment exchange in relation with nourishments and in the presence of protection structures. The effectiveness of the adopted interventions to combat erosion, and to cope with future climate change-related impacts, appears not fully successful in the presence of an overall sediment deficit at the coast. This demonstrates the need for repeated monitoring of the emerged and submerged beach in such a critical setting.

Building with Nature as integrated design of infrastructures

Many people associate Building with Nature with its flagship project, the Sand Motor. This mega-nourishment redefined the role of natural processes in civil engineering projects, demonstrating that instead of ‘do no harm’ as the highest possible supporting goal of coastal infrastructure, the design could incorporate natural processes to attain societal and ecological goals. As such, the Sand Motor represents a key example of the integrated design of civil infrastructures. In this contribution, we pursue an improved understanding of the integrated design of civil infrastructures, by comparing the illustrative example of the Sand Motor against a framework based on transport infrastructures and the occasional flood defence. It turns out that application of a framework from one domain to another - a conscious act of interdisciplinary learning - results in a modification of that framework. Although the domain of Building with Nature fits well with many existing attributes of integrated design for civil infrastructures (the life cycle approach, adaptive design and adding functionalities), its key attribute (dynamics) adds a unique box to the integrality index. This intellectual effort raises two issues. It demonstrates that our understanding of integrated design is rather specific for different infrastructure-domains. Second, it is likely that the bandwidth of uncertainty that is key to the incorporation of natural processes in infrastructure design, and the changing behaviour of the structure itself in the maintenance phase, has implications for the governance regime of such infrastructures.

The role of natural processes in the formation of the fauna of water and ground organisms of Baikal Lake

The relationship between the paleogeographic events of the Neogene and the Quaternary period on Lake Baikal with the formation of the faunistic complexes of fish, birds, and their parasites is analyzed in the article. The composition of fish parasites confirms that the representatives of endemic Baikal Cottoidei passed the most prolonged isolation in Baikal, and the fish of the boreal lowland complex settled the lake relatively recently and may have penetrated here repeatedly. The current composition of aquatic birds indicates the tense conditions of their habitat in the Baikal region in the Quaternary and the significant variability of their fauna in the Pleistocene climatic cycles due to the periodic colonization of Baikal by birds.

Application of GIS methods to retrieve orientation patterns from imagery; a case study from Beds I and II, Olduvai Gorge (Tanzania)

The role of natural processes in the formation of the Bed I and II sites at Olduvai Gorge (Tanzania) remains the subject of much debate, five decades after their original excavation. Preferred orientation of items is indicative of water disturbance, but compass bearings were not available in Mary Leakey's (1971) study. Using GIS methods, we have vectorized maps from 1960s excavations at Olduvai, and applied a range of statistical techniques to calculate items strike. The GIS analysis suggests strongly preferred orientation patterns in Bed I, and more heterogeneous angular histograms in Bed II. Two complementary lines of evidence support these results. Firstly, modelling of potential mapping errors provides a large interval of confidence for preferred orientation patterns. Second, the GIS study was extended to photographs of the earlier excavations and to maps from recent fieldwork at Olduvai; both yielded patterned arrangement of lithics and bones, and are consistent with results based on the analysis of the 1960s maps, i.e. a large number of the Bed I and II assemblages are preferentially oriented. These results highlight the potential of GIS applications to the analysis of imagery in Stone Age studies, and bear important implications for the understanding of the role of natural agents in site formation processes at Olduvai.

Long term relation between solar activity and surface temperature at different geographical regions

AbstractGlobal suface temperature has showed a rise trend in the last 150 years. This has been mainly attributed to the anthropogenic induced grenhouse gases emissions. However, the role of natural processes is not completely understood and should not be underestimated. In this work, we compare the long term variability of solar activity (as quantified by the sunspot number) with several surface temperature series from different geographical regions (global, hemispheric and latitudinal ranges). The interval of analysis is 1880-2005. The data are analyzed with wavelet multiresolution technique. It has been found that the solar activity long term trend has a maximum around 1970, while air surface temperature series showed maximum (still rising) at 2005. There are differences in the long term trend for Northern and Southern hemispheres. These differences and the relation with solar activity are discussed in this work.

Clearances and Clearings: Deforestation in Mesolithic/Neolithic Britain

Clearances, interpreted from pollen records during the Mesolithic and Neolithic of Europe, are generally ascribed to purposive deforestation which is compatible with the transition model, whereby early Neolithic economic strategies are a development of late Mesolithic intensification of wild plant food husbandry. This paper considers the role of natural processes in creating clearings and the role of inadvertent impact of human activity on forest processes, including woodland regeneration. The role of climate, wind‐throw and lightning strikes in creating clearings and forest instability is emphasised and the evidence discussed from sites which may be interpreted as resulting from opportunistic human use of natural clearings. Unfortunately, regional pollen diagrams lack sufficient spatial resolution to detect the size of isolated clearings or establish the spatial variation in forest composition that was intimately related both to forest ecology and the effects of subtle human impacts. This may be the major reason for an apparent contradiction between pollen evidence of Neolithic impact and the archaeological record. Moreover, early Neolithic agricultural activity may have been concentrated in valley bottoms, which is undetectable in regional pollen diagrams. Alternative models need to be considered, which include culturally specific exploitation of the local environment, along with the inadvertent ecological repercussions of pre‐agricultural and early‐agricultural human activities in naturally dynamic woodlands.

Cave sites, faunal analysis, and Big-Game Hunters of the Great Basin: A caution

Deposits of inferred natural origin excavated at Mineral Hill Cave, north-central Nevada, exhibit a similarity to the reported evidence for “Big-Game Hunters” from cave sites in the Great Basin. Split bone and charcoal were observed throughout the deposits. In addition, the remains of a number of animal taxa including several Pleistocene genera, which are considered to have been of economic importance, were recovered from the deposits. These findings suggest that the role of natural processes in cave deposition is of crucial importance in understanding cave-site archaeology.

The Role of Natural Processes in the Design of Cities

The city is a part of nature, albeit altered. For the most part, the builders of cities have disregarded this fact, with dangerous and costly consequences: increased flooding, pollution, and energy demands, depletion of resources, and higher construction and maintenance costs. In recent years, scientists have documented the character of the urban, as distinct from the more rural, natural environment. This current understanding of nature in cities affords a tremendous opportunity for a new direction in city planning and design, one which has been shown to yield substantial economic, aesthetic, health, and safety benefits. Many cities, both in Europe and North America, have applied this knowledge piecemeal with great success. But to date, no city has implemented a comprehensive program which addresses all factors of the urban natural environment. The integration of natural processes with other concerns of the city's social, economic, and physical environment will result in healthier, safer, and more beautiful cities which are less costly to build and maintain.