Arctic climate changes in the 21st century: Ensemble model estimates accounting for realism in present-day climate simulation

In the course of forecasting future climate changes in the Arctic Region based on calculations and an ensemble of the state-of-the-art global climate models, the results depend on the method of construction the statistics from the models.     

Paleoanalogues of global warming in the 21st century

On the basis of landscape-climatic reconstructions for warming periods in the past, likely scenarios of future global warming have been developed for various warming levels that might be reached during the current century. The paleoanalogue of global warming by 0.7–1°C is the Holocene climatic optimum (5.5–6 ka B.P.) and that by 1.7–2°C is the last interglacial optimum (about 125 ka B.P.). The complex analysis concerning response of the principal ecosystem components to the expected warming signifies that there will not be any shifts of vegetation zones during the 21st century; reconstruction will touch only the internal structure of vegetable associations and broadening of interzonal ecotones.     

Statistical radio astronomy of the 21st century

The exponential development of radio-astronomy methods (sensitivity, resolution, depth of surveys, etc) has led to the need for new methods aimed at distinguishing weak signals in the midst of numerous background signals, as has long been the case for radio astronomy at meter wavelengths. Centimeter-wavelength data accumulated with existing radio telescopes (such as the RATAN-600 reflector—the largest radio telescope in Russia) are presented, and expected problems for major new radio telescopes of the 21st century, such as the Square Kilometer Array, are discussed. The effectiveness of using certain tested methods to derive astrophysically important results through reasonable statistical processing of large datasets is shown. In experiments conducted with RATAN-600, these methods lead to an enhancement in sensitivity by an order of magnitude compared with the sensitivity of a resolving element.     

论新时期地下水开发利用与管理的新使命

1994年本文作者曾在本刊发表文章 ,论述了地下水研究面临的历史转变。面对新世纪创造新辉煌的期盼 ,时过七年 ,在人类已跨入新世纪 ,面临创造新辉煌的形势下 ,地下水战线也应有新的作为、新的进展。本文论述了新时期在地下水开发利用与管理领域面临的应有转变和主要任务 :( 1)地下水开发与经营的指导思想要从比较放任 ,转变到高效利用与永续经营 ;( 2 )在三水统观统管联合运用中要把地下水作为珍贵后备水资源和抗旱的救命水加以对待 ;( 3)要把保护水质不受污染作为地下水管理的突出任务 ,要在重点地区建立地下水保护带 ;( 4)要建立和完善包括水位、水质动态观测在内的水环境综合观测网站 ,加强对地下水的全面观测 ;( 5 )要认真总结 5 0年来的地下水开发利用及管理工作 ,制定未来 30年的地下水事业发展规划 ;( 6 )要完善地下水开发利用保护法规 ;( 7)理顺地下水专业人才的培养渠道 ,认真培养地下水领域的高级专门人才 ;( 8)加强信息网建设 ,办好《地下水》刊物 ,在不断提高地下水科技水平的同时 ,重视科普宣传     

Man and the water cycle: challenges for the 21st century

Water is essential to life. Modern, technological societies use huge quantities of this precious liquid. The hydrologic (water) cycle represents the movement of water through the earth's environmental systems. Humankind primarily makes use of three parts of the hydrologic cycle for its water needs: rivers, lakes, and groundwater. Our use of these components of the water cycle has had a variety of deleterious effects. Many large rivers have had their flow regimes modified and suffered from pollution with attendant negative effects of riverine, estuarial, and oceanic ecosystems. Lakes have suffered most seriously from anthropogenic caused pollution but have been impacted by introduction of exotic biota and regime alteration as well. Groundwater, because of its slow rate of replenishment, has suffered from depletion and accumulating pollutants. Looking toward the next century, we must alter our management of water and put it on an ecologically sustainable footing. This involves three key actions: (1) developing an ecosystems approach, (2) improving the water knowledge base, and (3) promoting improved management and cooperation, both nationally and internationally.     

Variations in the Duration of the Navigation Period along the Northern Sea Route in the 21st Century Based on Simulations with an Ensemble of Climatic Models: Bayesian Estimates

As global warming continues in the 21st century, one can expect a significant increase in the duration of the navigation period along the Northern Sea Route. In this study we found that, according to the representative concentration pathways 4.5 and 8.5 scenarios of the anthropogenic impact, the expected duration of the navigation period along the Northern Sea Route in the middle of the 21st century would be two to three months and three to six months by the end of the century.     

Water for sustainable development in the 21st century: a global perspective

Many arid and semi-arid countries are feeling water crisis already at present, and the problem will become more serious in the 21st century. Global water consumption will increase, 10-fold during this century, and the increasing trend will continue well into the 21st century. This Presidential Address to the International Water Reserves Association discusses the reasons for the water crisis, and the major water issues of the 21st century. Among those issues are water conservation and efficient use of water, water pricing and cost recovery, social and environmental considerations, institutional responses to better management, management of international water bodies and proper analytical frameworks.     

21世纪北半球中高纬度净初级生产力(NPP)变化及其与气候因子之间的关系

基于CMIP5模式模拟的净初级生产力(NPP), 对21世纪初期(2016-2035年), 中期(2046-2065年)和末期(2080-2099年)三种排放情景下(RCP2.6、RCP4.5、RCP8.5)北半球中高纬度陆地NPP的时空变化进行了预估, 并结合气候因子分析了NPP的变化和气温、降水、辐射之间的关系. 结果表明: 相对于1986-2005年, 21世纪北半球中高纬度陆地NPP呈增加趋势, RCP8.5情景下NPP的增加比RCP2.6和RCP4.5情景下更为明显; 在季节变化上, 北半球中高纬度NPP也以增加为主, 且NPP在夏季, 尤其是6月增加最显著. NPP对气候变化的响应存在明显的区域差异性, 在中低排放情景下(RCP2.6、RCP4.5), 相对于1986-2005年, 21世纪北半球中高纬度地区温度显著影响的范围在逐渐缩小, 而辐射和降水显著影响的范围在扩大. 在高排放情景下(RCP8.5), 21世纪北半球中高纬度地区NPP的变化主要与温度有关.     

面临21世纪的中国地下水模拟问题

本文在扼要介绍了我国地下水模拟的发展历程和现状后,着重探讨了面向２１世纪中国地下水模拟发展中存在的几个带全局性的关键总是及对其对策;     

National territorial planning at the turn of the 21st century

In the early stages of economic development in Korea, national territorial planning was used as a policy tool to guide spatial structure and to provide physical infrastructure for urban and industrial development. Such a top-down approach was inevitable because Korea maintained the centralized political and government system until the early 1990s. Circumstances, however, have changed recently since the 1990s with progress in democratization and localization. In addition, forces of globalization are making significant impacts on the parameters of national territorial planning. Reflecting these changes in both internal and external conditions, the Fourth National Territorial Plan (2000–2020) has adopted a different approach from the past three territorial plans. This paper reviews the socio-economic background that necessitated such changes in approaches to national territorial planning. A major thrust of the Fourth Plan, a focus on emergent or anticipated planning issues in Korea, is discussed. Finally, the paper examines the rationale for long-term strategic planning in the highly fluctuating situation facing Korean society in the new century.     

二十一世纪初地质工作的若干思考

经济全球化、世界范围内经济结构的调整和高新技术的飞速发展，使２１世纪成为一个充满机遇和挑战的世纪。按照我国经济社会发展的总体部署，从２１世纪伊始，我国要实现“十五”计划、第三步发展战略所确定的目标，到２１世纪中叶，人均国民生产总值要达到中等发达国家水平，人民生活比较富裕，基本实现现代化。这一目标必须在实施可持续发展的总体要求下实现，任务十分艰巨。面对新的形势，地质工作者承担着十分繁重的历史使命。如何做好新世纪初的地质工作，使地质工作既能满足国民经济建设和社会发展的需要，又能实现自身的健康发展，是…