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81.
As global temperatures go up and incomes rise, air conditioner sales are poised to increase dramatically. Recent studies explore the potential economic and environmental impacts of this growth, but relatively little attention has been paid to the implications for inequality. In this paper we use household-level microdata from 16 countries to characterize empirically the relationship between climate, income, and residential air conditioning. We show that both current and future air conditioner usage is concentrated among high-income households. Not only do richer countries have much more air conditioning than poorer countries, but within countries adoption is highly concentrated among high-income households. The pattern of adoption is particularly stark in relatively low-income countries such as Pakistan, where we show that the vast majority of adoption between now and 2050 will be concentrated among the upper income tercile. We use our model to forecast future adoption, show how patterns vary across countries and income levels, and discuss what these patterns mean for health, productivity, and educational inequality. 相似文献
82.
Magdalena Szuman Christian Berndt Colin Jacobs Angus Best 《Marine Geophysical Researches》2006,27(3):167-180
This study uses three acoustic instruments (different in their operating frequencies, 13, 3.5, and 6–10 kHz, and deployment
type, hull-mounted, surface-towed and deep-towed) to investigate and characterize the acoustic response of seafloor NE of
Oman in a frequency-independent manner. High-resolution control was achieved by having selected areas of our acoustic transects
ground-truthed by sampling and/or sea-floor photography. On the regional scale, the greatest degree of change in backscatter
amplitude was correlated with major changes of seabed morphology and lithology. However, small-scale roughness had the biggest
effect on amplitude on the local scale, i.e. within each area of specific seafloor type. The study also shows that seafloor
reflection amplitude changes are far more easily detected by deep-towed instrument than by surface-towed or hull-mounted systems.
Whilst there are significant changes in bioturbation types and density along the transects, the suite of instruments deployed
was not able to pick up the effect of the bioturbation on acoustic signals. 相似文献
83.
用数值方法研究了行星尺度阻塞波和天气尺度波之间的相互作用,得到在涡源强迫下,当不存在地形时,大尺度流场可发展成偶极型阻塞,瞬时流场分裂成南北对称的2支,总流场可以看到明显的多涡结构;加上双波地形后,大尺度流场发展成Ω型阻塞,瞬时流场同样分裂成2支,但北支要明显强于南支.而且通过一系列对比试验发现,适当的弱的基本西风气流是阻塞发生的有利条件.此外,讨论了初始阻塞和造波器(扰动源)位置的配置,以及造波器关闭时间的不同对阻塞强度和生命周期的可能影响. 相似文献
84.
“5•12”汶川大地震发生后,中国国土资源航空物探遥感中心在空军、总参等大力支持和协助下,快速获取了北川、汶川等极重灾区的航空遥感资料。本文介绍了以航空遥感资料为主,结合北京1号小卫星、CBERS-02B等卫星数据快速调查地震堰塞湖的成果。 相似文献
85.
86.
Start-of-season data are more and more used to qualify the land surface phenology trends in relation with climate variability and, more rarely, with human land management. In this paper, we compared the phenology of rangeland vs cropped land in the Sahel belt of Africa, using the only currently available global phenology product (MODIS MCD12Q2 – Land Cover Dynamics Yearly), and an enhanced crop mask of Mali. The differences in terms of start-of-season (SOS) are spatially (north south gradient), and temporally (10 years, 2001–2009) analyzed in bioclimatic terms. Our results show that globally the MODIS MCD12Q2 SOS dates of croplands and rangelands differ, and that these differences depend on the bioclimatic zone. In Sahelian and Guinean regions, cropland vegetation begins to grow earlier than rangeland vegetation (8-day and 4-day advance, respectively). Between, in the Sudanian and Sudano-Sahelian parts of Mali, rangeland vegetation greens about one week earlier than croplands. These results are discussed in the context of the land surface heterogeneity at MODIS scale, and in the context of the natural vegetation ecology. These results could help interpreting phenological trends in climate change analysis. 相似文献
87.
《The Professional geographer》2013,65(1):22-25
Ten Years o f Physicogeographic Research in Hungary Antarctic Snow and Ice Studies 相似文献
88.
Source of major ions from an ice core of the No. 12 Glacier in Laohugou Valley, Qilian Mountain 总被引:1,自引:1,他引:0
XiaoQing Cui JiaWen Ren Xiang Qin WenTao Du WeiJun Sun GuangMingYu XiaoXiang Wang WeiZhen Sun 《寒旱区科学》2010,2(6):0522-0528
In June 2006,a 20.12 m shallow ice core was recovered from an elevation of 5,040 m in the northern branch firn basin of No.12 Glacier,Great Snow Mountain,in the western part of Qilian Mountain,China.Isotopes(δ 18 O),major soluble ions,and radionuclide(β-activity) measurements from the ice core revealed a 46-year record(1960-2006).In this paper,the method of sea-salt ion tracer,correlation analysis and trend analysis were used in this research to confirm the source of the chemical composition.The correlation analysis and HYSPLIT backward trajectory analysis suggests that atmospheric soluble dust species dominate the chemical signature. 相似文献
89.
祁连山老虎沟12号冰川雷达测厚和冰下地形特征研究 总被引:3,自引:3,他引:0
冰川地形是构建冰川流动模型的基础,对于认识冰川响应气候变化的动力机制具有重要意义.在2009年和2014年消融季,使用探地雷达对祁连山老虎沟12号冰川进行了厚度测量和冰下地形观测,获得了沿冰川中流线和多条横剖面的厚度资料,并对中流线上的厚度分布特征和槽谷形态进行了研究.研究结果表明,东、西支冰川的平均厚度分别为190m和150m,东支冰川冰下地形起伏大于西支,支冰川的表面坡度都较缓和.东、西支冰川进入汇合区时厚度分别为122m和157m,由于支冰川的横向挤压和汇流,汇合区中部冰川厚度增加到162m.冰川槽谷形态具有空间差异,东、西支冰川槽谷形态近似于对称的V型,但是在冰川汇合区,槽谷底部变宽,边坡变缓,发育有不对称槽谷. 相似文献
90.
2008年10月和2009年10月在祁连山老虎沟12号冰川积累区采集了2个雪坑样品, 通过样品中δ18O、可溶性离子、不溶性微粒的变化特点划分了雪坑季节. 2008年雪坑季节变化信号明显, 而2009年雪坑不明显, 微粒浓度、Ca2+与Mg2+含量在春季较高. 离子平衡、pH值、电导率及同期气象记录观测资料均显示, 2009年雪坑受淋溶影响较大. 淋溶强烈时, 受融水造成的粉尘溶解及离子淋溶的影响, 雪坑中微粒与Ca2+、Mg2+变化趋势不甚一致; 与Ca2+相比, Mg2+变化能够较好表征微粒的变化; d>5 μm的微粒可能更易于溶解迁移. 通过分析室内雪冰样品在液态下的变化, 发现伴随静置过程微粒的质量浓度呈下降的趋势, 期间Ca2+、Mg2+却呈现增加的变化, 可能与碳酸盐矿物的溶解有关. 相似文献