A Statistical Analysis of Extreme Hot Characteristics and their Relationships with Urbanization in Southern China during 1971–2020

Author(s):  
Huanyan Gao ◽  
Yali Luo ◽  
Xiaoling Jiang ◽  
Da-Lin Zhang ◽  
Yang Chen ◽  
...  

AbstractIn this study, the total days, mean duration, and intensity of extreme hot events over southern China during the 1971–2020 warm seasons are analyzed, based on daily maximum and minimum temperatures, by comparing the newly proposed independent hot day (IHD), independent warm night (IWN), and compound extreme (CMPD, i.e., the continuous occurrences of hot days and hot nights) to the traditionally defined hot day and warm night. Relationships between the hot extremes and urbanization are explored with 1-km resolution population density data. Results show obvious differences in the spatial distributions between IHD, IWN, and CMPD over southern China. Positive correlations of 0.43, 0.41 and 0.37 are found between the population density and the total days, mean duration and mean intensity of CMPD, respectively, which are qualitatively similar to those using the traditional hot days and warm nights. In contrast, negative correlations between the IHD and IWN indices and the population density are found, as those indices are more apparent over rural areas. Moreover, total days, mean duration and mean intensity of CMPD increase significantly with trends of about 103% decade-1, 21% decade-1 and 38% decade-1, respectively, during the rapid urbanization period from mid-1990s to 2020, which are about 4.9, 2.1 and 2.4 times of their counterparts from 1970 to mid-1990s, while less significant and smaller differences between the two eras are found in IHD and IWN. These results will provide a new scientific basis for evaluating climate models of hot extremes in southern China and have important implications for the other urbanized regions as well.

2020 ◽  
Vol 3 (6) ◽  
pp. 8-11
Author(s):  
Bakaev Zh. N.

According to the authors, the prevalence of SOPR diseases is from 3 to 20%.In a study of 1573 residents of southern China in two age groups who use tobacco and alcohol, the incidence of SOPR was higher among men living in rural areas compared to urban residents. Among women aged 35-44 years, the incidence was higher in urban women, and in the 65-77-year-old group in rural women. In the course of studies in Brazil, among 335 patients older than 60 years, 646 diseases of the SOPR were identified. Similar results were obtained in the analysis of SOPR diseases in the Volgograd region of the Russian Federation


Author(s):  
N.N. Balashova ◽  
◽  
D.A. Korobeynikov ◽  
S.A. Popova ◽  
◽  
...  

Typologization of rural areas, taking into account differences in population density and level of socio-economic development, is necessary to identify “growth points” and strategic sustainability benchmarks. The method of integrated assessment of the level of socio-economic development of rural territories is proposed, according to which the grouping of Russian regions is carried out. Applying data on rural population density to the results of calculations allowed us to identify 12 typological groups, in the context of which unified recommendations on sustainable development of territories should be formed.


2020 ◽  
pp. 002073142098374
Author(s):  
Ashutosh Pandey ◽  
Nitin Kishore Saxena

The purpose of this study is to find the demographic factors associated with the spread of COVID-19 and to suggest a measure for identifying the effectiveness of government policies in controlling COVID-19. The study hypothesizes that the cumulative number of confirmed COVID-19 patients depends on the urban population, rural population, number of persons older than 50, population density, and poverty rate. A log-linear model is used to test the stated hypothesis, with the cumulative number of confirmed COVID-19 patients up to period [Formula: see text] as a dependent variable and demographic factors as an independent variable. The policy effectiveness indicator is calculated by taking the difference of the COVID rank of the [Formula: see text]th state based on the predicted model and the actual COVID rank of the [Formula: see text]th state[Formula: see text]Our study finds that the urban population significantly impacts the spread of COVID-19. On the other hand, demographic factors such as rural population, density, and age structure do not impact the spread of COVID-19 significantly. Thus, people residing in urban areas face a significant threat of COVID-19 as compared to people in rural areas.


Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 896
Author(s):  
Qing Ye ◽  
Xiaoguang Yang ◽  
Wenjuan Xie ◽  
Junmeng Yao ◽  
Zhe Cai

During the rice growing season, farmers’ decisions about cropping systems and seed varieties directly affect the utilization of heat resource, and eventually affect the potential yield. In this study, we used the hourly accumulated temperature model to calculate the available heat resource as well as the effective heat resource in southern China. We conducted a spatiotemporal analysis of the heat resource effectiveness during rice growing season and an impact assessment of heat resource effectiveness on rice potential yield and cereal yield reduction. The results showed that, during the period of 1951–2015, heat resource effectiveness generally declined in the rice cropping area of southern China. And this decrease worsened during the most recent three decades compared with the period of 1951–1980. A strong correlation was detected between heat resource effectiveness and rice potential yield in the study area. When the effective heat resource during the growing season increased by 1 °C·d, rice potential yield would increase by 14 kg ha−1. For each percentage increase in heat resource effectiveness, the rice potential yield reduction rate would go down by 0.65%. This agro-climatological study aims to offer a scientific basis for rice production decisions in southern China, such as when to plant, which varieties to choose and so on.


2014 ◽  
Vol 53 (9) ◽  
pp. 2148-2162 ◽  
Author(s):  
Bárbara Tencer ◽  
Andrew Weaver ◽  
Francis Zwiers

AbstractThe occurrence of individual extremes such as temperature and precipitation extremes can have a great impact on the environment. Agriculture, energy demands, and human health, among other activities, can be affected by extremely high or low temperatures and by extremely dry or wet conditions. The simultaneous or proximate occurrence of both types of extremes could lead to even more profound consequences, however. For example, a dry period can have more negative consequences on agriculture if it is concomitant with or followed by a period of extremely high temperatures. This study analyzes the joint occurrence of very wet conditions and high/low temperature events at stations in Canada. More than one-half of the stations showed a significant positive relationship at the daily time scale between warm nights (daily minimum temperature greater than the 90th percentile) or warm days (daily maximum temperature above the 90th percentile) and heavy-precipitation events (daily precipitation exceeding the 75th percentile), with the greater frequencies found for the east and southwest coasts during autumn and winter. Cold days (daily maximum temperature below the 10th percentile) occur together with intense precipitation more frequently during spring and summer. Simulations by regional climate models show good agreement with observations in the seasonal and spatial variability of the joint distribution, especially when an ensemble of simulations was used.


Land ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 514
Author(s):  
Hongzhang Xu ◽  
Jamie Pittock ◽  
Katherine A. Daniell

The adverse effects of rapid urbanization are of global concern. Careful planning for and accommodation of accelerating urbanization and citizenization (i.e., migrants gaining official urban residency) may be the best approach to limit some of the worst impacts. However, we find that another trajectory may be possible: one linked to the rural development plan adopted in the latest Chinese national development strategy. This plan aims to build rural areas as attractive areas for settlement by 2050 rather than to further urbanize with more people in cities. We assess the political motivations and challenges behind this choice to develop rural areas based on a literature review and empirical case analysis. After assessing the rural and urban policy subsystem, we find five socio-political drivers behind China’s rural development strategy, namely ensuring food security, promoting culture and heritage, addressing overcapacity, emphasizing environmental protection and eradicating poverty. To develop rural areas, China needs to effectively resolve three dilemmas: (1) implementing decentralized policies under central supervision; (2) deploying limited resources efficiently to achieve targets; and (3) addressing competing narratives in current policies. Involving more rural community voices, adopting multiple forms of local governance, and identifying and mitigating negative project impacts can be the starting points to manage these dilemmas.


2021 ◽  
Author(s):  
Mastawesha Misganaw Engdaw ◽  
Andrew Ballinger ◽  
Gabriele Hegerl ◽  
Andrea Steiner

<p>In this study, we aim at quantifying the contribution of different forcings to changes in temperature extremes over 1981–2020 using CMIP6 climate model simulations. We first assess the changes in extreme hot and cold temperatures defined as days below 10% and above 90% of daily minimum temperature (TN10 and TN90) and daily maximum temperature (TX10 and TX90). We compute the change in percentage of extreme days per season for October-March (ONDJFM) and April-September (AMJJAS). Spatial and temporal trends are quantified using multi-model mean of all-forcings simulations. The same indices will be computed from aerosols-, greenhouse gases- and natural-only forcing simulations. The trends estimated from all-forcings simulations are then attributed to different forcings (aerosols-, greenhouse gases-, and natural-only) by considering uncertainties not only in amplitude but also in response patterns of climate models. The new statistical approach to climate change detection and attribution method by Ribes et al. (2017) is used to quantify the contribution of human-induced climate change. Preliminary results of the attribution analysis show that anthropogenic climate change has the largest contribution to the changes in temperature extremes in different regions of the world.</p><p><strong>Keywords:</strong> climate change, temperature, extreme events, attribution, CMIP6</p><p> </p><p><strong>Acknowledgement:</strong> This work was funded by the Austrian Science Fund (FWF) under Research Grant W1256 (Doctoral Programme Climate Change: Uncertainties, Thresholds and Coping Strategies)</p>


Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 666 ◽  
Author(s):  
Juyang Liao ◽  
Linping Zhang ◽  
Yan Liu ◽  
Qiaoyun Li ◽  
Danxia Chen ◽  
...  

Food supply from forests is a fundamental component of forest ecosystem services, but information relating to suitability for human consumption and sustainable utilization of non-timber forest products (NTFPs) in developing countries is lacking. To address this gap in knowledge, diverse datasets of edible plants and macro-fungi were obtained from field collections, historical publications, and community surveys across seven cities in Guangdong Province (GP), southern China. Seven edible parts and five food categories of plant species were classified according to usage and specific nutrient components. Edible plant species were also categorized into different seasons and life forms. Our results show that at least 100 plant species (with 64 plant species producing fruit) and 20 macro-fungi were commonly used as edible forest products in subtropical GP. There were 55 and 57 species providing edible parts in summer and autumn, respectively. Many edible plants had multiple uses. Tree and herbaceous species made up the majority of the total. Our study provides evidence that both edible plants and macro-fungi can enrich the food supply for residents in rural and urban areas by acting as supplemental resources. We therefore suggest that, in spite of the prevalence of imported foods due to modern infrastructure, edible NTFPs from subtropical forests might be leveraged to support the increasing demand for food in an era of rapid urbanization and global change.


2008 ◽  
Vol 8 (2) ◽  
pp. 7781-7804 ◽  
Author(s):  
K.-J. Liao ◽  
E. Tagaris ◽  
K. Manomaiphiboon ◽  
C. Wang ◽  
J.-H. Woo ◽  
...  

Abstract. Impacts of uncertain climate forecasts on future regional air quality are investigated using downscaled MM5 meteorological fields from the NASA GISS and MIT IGSM global climate models and the CMAQ model in 2050 in the continental US. Three future climate scenarios: high-extreme, low-extreme and base, are developed for regional air quality simulations. GISS, with the IPCC A1B scenario, is used for the base case. IGSM results, in the form of probabilistic distributions, are used to perturb the base case climate to provide 0.5th and 99.5th percentile climate scenarios. Impacts of the extreme climate scenarios on concentrations of summertime fourth-highest daily maximum 8-h average ozone are predicted to be up to 10 ppbv (about one-eighth of the current NAAQS of ozone) in some urban areas, though average differences in ozone concentrations are about 1–2 ppbv on a regional basis. Differences between the extreme and base scenarios in annualized PM2.5 levels are very location dependent and predicted to range between −1.0 and +1.5 μg m−3. Future annualized PM2.5 is less sensitive to the extreme climate scenarios than summertime peak ozone since precipitation scavenging is only slightly affected by the extreme climate scenarios examined. Relative abundances of biogenic VOC and anthropogenic NOx lead to the areas that are most responsive to climate change. Such areas may find that climate change can significantly offset air quality improvements from emissions reductions, particularly during the most severe episodes.


2020 ◽  
pp. 167-176
Author(s):  
Ahmad El-Atrash

The urban development and rapid urbanization that the West Bank, including occupied East Jerusalem and Gaza Strip have recently encountered have adversely affected the quality and availability of open spaces inside the Palestinian urban and rural areas. Public spaces are fundamental in the lives of any community striving to achieve a sustainable and inclusive environment and improve the quality of life of its inhabitants. In that respect, the prevailing planning practices fall short in terms of adequately addressing the provision of public spaces. Laws and regulations are designed to focus on limited physical properties of buildings (e.g. building design, elevation, heights, setbacks, parking, etc.,) with little or no attention to the residual space, inevitably, created between those blocks. Lands are chiefly privately owned, and considered of a very high value due to the artificial land scarcity phenomenon resulted from the geo-political classification of the West Bank Existing public spaces are not welcoming to the general public. Spaces are misplaced and scattered, they offer pre-defined activities and an inflexible environment. Many parts of the society feel alienated to such public spaces, created by a top-down process with minimal integration of their needs and aspirations.


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