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121.
Ski resort abandonment is more frequent due to global warming, which progressively reduces snowpack and persistence. However, projects aiming for new resorts in the Apennines have proliferated. Such economic investments are risky, especially without long-term data on snow cover duration. Our aim, thus, is to provide the first census of abandoned ski resorts in the Apennines and compare them with the resorts currently open to understand the causes that led to their abandonment. Subsequently, we explore factors behind resort failure by analyzing the relationships between climatic, geomorphological, and economic variables. Overall, we found 101 ski resorts in the Apennines, of which 28 were open, 41 closed and abandoned and 32 partially closed (i.e., closed in more than at least 7 years in the last 10 years). The closed and partially closed resorts represent 358 km of ski slopes (44% of total available). The number of structures per resort (i.e. ski lifts, chair lifts) is higher for open compared to partially closed and closed ones. Notably, the maximum elevation reached by the resorts is higher for those open (1793 m a.s.l.) than for those partially closed (1687 m a.s.l.) and especially those closed (1577 m a.s.l.). Finally, the mean size of the resorts in terms of skiable track length is larger for open (15.7 km) than partially closed (7.1 km) and closed resorts (3.2 km). The average duration of operation for abandoned resorts is 29.5 years, varying from a maximum of 56 years to a minimum of 0 years for two sites that were never opened after reconstruction. The year of abandonment is positively associated with the maximum elevation, size, and duration of operation. Furthermore, the duration of operation is negatively correlated with the construction year. Our multivariate analysis confirms and strengthens the hypothesis for the causes that lead to abandonment are multi-factorial. Most of the closed resorts are located at low altitude and have small ski areas although some higher altitude sites have also been abandoned in recent years. This information can be useful for investors, policymakers, and stakeholders who should use it as a starting point when designing and planning new resorts to avoid future failures and the loss of public money. 相似文献
122.
SAFAROV Mustafo KANG Shichang MURODOV Murodkhudzha BANERJEE Abhishek NAVRUZSHOEV Hofiz GULAYOZOV Majid FAZYLOV Ali VOSIDOV Firdavs 《山地科学学报》2024,47(9):2967-2985
Glaciers in the Pamir region are experiencing rapid melting and receding due to climate change, which has a significant implication for the Amu Darya river basin. Predominantly, surging glaciers, which undergo unpredictable advances, are potentially leading to the obstruction of high-altitude river channels and also glacial lake outburst floods. This study investigates surging glaciers in the Pamir region, specifically focusing on the Medvezhiy (M) and Russian Geographical Society (RGS) glaciers, using long-term reanalysis data records, unmanned aerial vehicles (UAVs), and satellite data during the last decades. Significant changes in regional climate were identified, including increasing precipitation rates (13.3 mm/year) and land surface temperature (0.1℃/decade). Between 1991 to 2023, the RGS glacier experienced a significant advancement around 1448.3 ± 30.0 m, while the Medvezhiy glacier showed a decrease of -703.5 ± 30.0 m. There is a substantial increase in the number (from 19 to 75) and area (from 4889.7 ± 0.6 m2 to 15345.5 ± 0.6 m2) of RGS lakes along with supra-glacier ponds based on a comparison of ArcGIS base map in 2011 and high-resolution UAV data in 2023. For M glacier, number of lakes increased from 4 to 22 but the lake area declined from 10715.2 ± 0.6 to 365.6 ± 0.6 m2. It was noted that the largest lake in 2011 with an area of 10406.4 ± 0.6 m2 at the southeastern portion of the glacier was not observed in 2023 due to outburst. Both the glaciers have substantially impacted the river flow (Abdukahor river) by obstructing a significant proportion of river channel in recent years and might cause outburst floods. These findings enhance the understanding of glacier dynamics and their impacts on the surrounding areas, emphasizing the urgent need for continued monitoring and appropriate management strategies, with a specific focus on surging glaciers and the associated risks. 相似文献
123.
从气候变化风险的类别入手,详细阐述了气候变化主要灾害和次生灾害对保险业负债端的影响。作为市场化风险管理工具,保险业在减缓和适应气候变化方面持续发挥着重要作用。随着气候变化风险意识的不断增强,保险业不断推出创新产品实践,将应对气候变化纳入公司管理体系,并积极参与国际合作。保险监管也在推行气候变化应对相关意见。然而,保险业在应对气候变化的过程中仍然存在大量的问题、风险和挑战。未来,中国保险业应持续采取加快产品创新、提升风险管理、加强跨行业合作等措施,充分发挥风险保障作用,为服务国家适应气候变化战略做出重要贡献。
相似文献124.
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126.
气候暖干化对西北四省（区）农业种植结构的影响及调整方案 总被引：1，自引：0，他引：1
利用陕、甘、宁、青四省（区）141个气象站1961-2008年的气象要素值计算和分析得出,暖干化是西北四省（区）现代气候变化的基本特征。年平均气温表现为一致的增温趋势,每10年增温0.27℃,1996年是突变年。年降水量自1961年以来呈持续下降趋势,1986年是转折年,1987-2008年年平均降水量比1961-1986年平均减少20-40mm。以黄河为界,黄河以东降水量呈减少趋势,每10年减少10-40mm;黄河以西呈增多趋势,每10年增加10mm左右,减少的幅度明显高于增加的幅度。进入21世纪,气候暖干化的势头有所减缓。在分析不同区域自然资源特点和气候暖干化及其对农作物影响特征的基础上,运用系统规划理论,采用气候生态相似原理,提出了陕、甘、宁、青四省（区）13个不同地域农业种植结构调整方案。为了加快农业结构调整进程,使农业结构调整方案收到明显的生态、社会和经济效益,提出了四个方面的保障措施。 相似文献
127.
128.
近50年疏勒河流域山区的气候变化及其对出山径流的影响 总被引：3，自引：0，他引：3
利用祁连山区水文站和气象站的观测数据,分析了近50年河西走廊西部疏勒河流域山区的气候变化及其对出山径流的影响。结果表明,受全球变暖的影响,疏勒河山区气候持续向暖湿转化,且各季气温均呈持续的上升趋势,山区降水量总体上亦呈增加趋势,年际波动比较剧烈。在各季降水量中,除夏季外其他各季降水量的增加比较显著,海拔3 000m以上中高山地带夏季降水量变化不大,3 000m以下中低山地带夏季降水量略有减少。受山区降水,尤其是3 000m以下中低山地带的降水量显著增加与气温上升所引起的冰雪融水补给的影响,疏勒河出山径流呈持续的增加趋势。由于夏季降水量并未增加,在年径流总量中所占比重最大的夏季径流量的增加主要是由于气温上升所引起的冰雪融水补给的增加所致。 相似文献
129.
The accumulation processes of loess in northeastern (NE) China record the varying characteristics of the East Asian Monsoons (EAM) and the evolution of the local environment. In this study, grain size end-member analysis of the Dajiugang (DJG) section deposited since the Last Glacial in Chifeng City, NE China was used to reveal the dynamic depositional characteristics of loess and environmental evolution of NE China. Results showed that the Chifeng loess comprises three grain size end-members (EM), EM1 (7.38 μm), EM2 (49.4 μm) and EM3 (90.00 μm), indicating the three transport dynamics of dust delivered to the region. The EM1 represents atmospheric dust as the background. The EM2, mainly derived from relatively distant-sources deposition, and EM3, material transported over a short distance, correspond to the intensity of southwesterly winds and the East Asian Winter Monsoon (EAWM), respectively. Results of climate reconstruction, combined with other records, showed that the climate was generally cold and dry with a strong EAWM and a weak East Asian summer monsoon (EASM) during the stadial-period [Marine Isotope Stage (MIS) 4 and MIS 2 stage]. The climate was predominantly warm and humid, with weak EAWM and surface winds and strong EASM in interstadial- period (MIS 3 and MIS 1 stage). Comparisons between indicators, e.g., EM3, the LR04 benthic δ18O stack and summer insolation at 65°N suggest that the strong EAWM is induced by increasing the Northern Hemisphere ice volume and reduced summer solar radiation. 相似文献
130.
建筑物变化检测在城市环境监测、土地规划管理和违章违规建筑识别等应用中具有重要作用。针对传统孪生神经网络在影像变化检测中存在的检测边界与实际边界吻合度低的问题,本文结合面向对象图像分析技术,提出一种基于面向对象孪生神经网络（Obj-SiamNet）的高分辨率遥感影像变化检测方法,利用模糊集理论自动融合多尺度变化检测结果,并通过生成对抗网络实现训练样本迁移。该方法应用在高分二号和高分七号高分辨率卫星影像中,并与基于时空自注意力的变化检测模型（STANet）、视觉变化检测网络（ChangeNet）和孪生UNet神经网络模型（Siam-NestedUNet）进行比较。结果表明：（1）融合面向对象多尺度分割的检测结果较单一尺度分割的检测结果,召回率最高提升32%,F1指数最高提升25%,全局总体误差（GTC）最高降低7%;（2）在样本数量有限的情况下,通过生成对抗网络进行样本迁移,与未使用样本迁移前的检测结果相比,召回率最高提升16%,F1指数最高提升14%,GTC降低了9%;（3）Obj-SiamNet方法较其他变化检测方法,整体检测精度得到提升,F1指数最高提升23%,GTC最高降低9%。该方法有效提高了建筑物变化检测在几何和属性方面的精度,并能有效利用开放地理数据集,降低了模型训练样本制作成本,提升了检测效率和适用性。 相似文献